Piano/PluginProcessor.cpp

#include "PluginProcessor.h"
#include "PluginEditor.h"
#include "BinaryData.h"
#include "PianoPhysicsData.h"
#include <algorithm>
#include <cmath>
#include <limits>

// SIMD headers for vectorization
#if defined(__SSE__) || defined(_M_X64) || defined(_M_IX86)
#include <xmmintrin.h>
#include <emmintrin.h>
#define USE_SSE 1
#endif

//==============================================================================
// FAST MATH LOOKUP TABLES AND APPROXIMATIONS
// These replace expensive std:: functions in the hot path
//==============================================================================

namespace FastMath {

// Lookup table sizes
static constexpr int kSinTableSize = 4096;
static constexpr int kSqrtTableSize = 4096;
static constexpr int kPowTableSize = 1024;

// Precomputed tables (initialized once)
static float sinTable[kSinTableSize];
static float sqrtTable[kSqrtTableSize];  // sqrt(x) for x in [0, 4]
static float pow2Table[kPowTableSize];   // 2^x for x in [-4, 4]
static bool tablesInitialized = false;

inline void initTables()
{
    if (tablesInitialized) return;
    
    // Sin table: covers [0, 2*PI]
    for (int i = 0; i < kSinTableSize; ++i)
    {
        float phase = (float) i / (float) kSinTableSize * juce::MathConstants<float>::twoPi;
        sinTable[i] = std::sin (phase);
    }
    
    // Sqrt table: covers [0, 4] (sufficient for normalized audio)
    for (int i = 0; i < kSqrtTableSize; ++i)
    {
        float x = (float) i / (float) kSqrtTableSize * 4.0f;
        sqrtTable[i] = std::sqrt (x);
    }
    
    // Pow2 table: covers 2^x for x in [-4, 4]
    for (int i = 0; i < kPowTableSize; ++i)
    {
        float x = ((float) i / (float) kPowTableSize) * 8.0f - 4.0f;
        pow2Table[i] = std::pow (2.0f, x);
    }
    
    tablesInitialized = true;
}

// Fast sine using lookup table with linear interpolation
inline float fastSin (float phase)
{
    // Wrap phase to [0, 2*PI]
    const float twoPi = juce::MathConstants<float>::twoPi;
    while (phase < 0.0f) phase += twoPi;
    while (phase >= twoPi) phase -= twoPi;
    
    float idx = phase / twoPi * (float) kSinTableSize;
    int i0 = (int) idx;
    float frac = idx - (float) i0;
    i0 = i0 & (kSinTableSize - 1);
    int i1 = (i0 + 1) & (kSinTableSize - 1);
    
    return sinTable[i0] + frac * (sinTable[i1] - sinTable[i0]);
}

// Fast sqrt approximation (for values 0-4, good for normalized audio)
inline float fastSqrt (float x)
{
    if (x <= 0.0f) return 0.0f;
    if (x >= 4.0f) return std::sqrt (x);  // Fallback for out of range
    
    float idx = x * (float) kSqrtTableSize * 0.25f;
    int i0 = (int) idx;
    float frac = idx - (float) i0;
    i0 = juce::jlimit (0, kSqrtTableSize - 2, i0);
    
    return sqrtTable[i0] + frac * (sqrtTable[i0 + 1] - sqrtTable[i0]);
}

// Fast inverse sqrt (Quake-style with one Newton-Raphson iteration)
inline float fastInvSqrt (float x)
{
    union { float f; uint32_t i; } conv;
    conv.f = x;
    conv.i = 0x5f3759df - (conv.i >> 1);
    conv.f *= 1.5f - (x * 0.5f * conv.f * conv.f);
    return conv.f;
}

// Fast pow(2, x) for x in [-4, 4]
inline float fastPow2 (float x)
{
    x = juce::jlimit (-4.0f, 3.99f, x);
    float idx = (x + 4.0f) * (float) kPowTableSize * 0.125f;
    int i0 = (int) idx;
    float frac = idx - (float) i0;
    i0 = juce::jlimit (0, kPowTableSize - 2, i0);
    
    return pow2Table[i0] + frac * (pow2Table[i0 + 1] - pow2Table[i0]);
}

// Fast pow approximation using log2/exp2 identity: x^y = 2^(y * log2(x))
// Only accurate for positive x, and limited y range
inline float fastPow (float base, float exp)
{
    if (base <= 0.0f) return 0.0f;
    if (exp == 0.0f) return 1.0f;
    if (exp == 1.0f) return base;
    if (exp == 2.0f) return base * base;
    if (exp == 0.5f) return fastSqrt (base);
    
    // Use actual pow for accuracy in edge cases
    return std::pow (base, exp);
}

// Fast tanh approximation (Pade approximant)
inline float fastTanh (float x)
{
    if (x < -3.0f) return -1.0f;
    if (x > 3.0f) return 1.0f;
    float x2 = x * x;
    return x * (27.0f + x2) / (27.0f + 9.0f * x2);
}

// Fast exp approximation
inline float fastExp (float x)
{
    x = juce::jlimit (-10.0f, 10.0f, x);
    // Schraudolph's approximation
    union { float f; int32_t i; } v;
    v.i = (int32_t) (12102203.0f * x + 1065353216.0f);
    return v.f;
}

} // namespace FastMath

// FIX #1: SharedBus struct moved to header file
// FIX #1: Removed thread_local - buses are now owned by FluteSynthAudioProcessor

static std::array<float,12> getTemperamentOffsetsByChoice (int choice);
static std::array<float,128> expandPitchClassOffsets (const std::array<float,12>& offsets);

static float mapHammerStiffnessToModel (float stiffnessSi)
{
    const float kMin = 4.0e8f;
    const float kMax = 1.0e10f;
    const float logMin = std::log10 (kMin);
    const float logMax = std::log10 (kMax);
    const float logK = std::log10 (juce::jlimit (kMin, kMax, stiffnessSi));
    const float t = (logK - logMin) / (logMax - logMin);
    return 200.0f + t * (20000.0f - 200.0f);
}

static float mapInharmonicityToDispersion (float bCoeff, float baseDispersion)
{
    const float bMin = 0.00018f;
    const float bMax = 0.40f;
    const float logMin = std::log10 (bMin);
    const float logMax = std::log10 (bMax);
    const float logB = std::log10 (juce::jlimit (bMin, bMax, bCoeff));
    const float t = (logB - logMin) / (logMax - logMin);
    const float scale = 0.25f + 0.85f * t;
    return juce::jlimit (0.0f, 0.50f, baseDispersion * scale);
}

//==============================================================================
// Voice (VA)
FluteVoice::FluteVoice (juce::AudioProcessorValueTreeState& state) : apvts (state)
{
    using FilterType = juce::dsp::StateVariableTPTFilterType;
    svf.setType (FilterType::lowpass);
    adsr.setSampleRate (44100.0); // updated in prepare()
}

bool FluteVoice::canPlaySound (juce::SynthesiserSound* s)
{
    return dynamic_cast<SimpleSound*> (s) != nullptr;
}

void FluteVoice::startNote (int midiNoteNumber, float velocity, juce::SynthesiserSound*, int)
{
    const int midiIdx = juce::jlimit (0, 127, midiNoteNumber);
    const float v = juce::jlimit (0.0f, 1.0f, velocity);
    // Velocity response: 24dB range with perceptual curve for expressive but audible dynamics
    const float velPerceptual = std::sqrt (v);
    velocityGain = juce::Decibels::decibelsToGain (juce::jmap (velPerceptual, 0.0f, 1.0f, -18.0f, 0.0f));
    const float cents = juce::jlimit (-100.0f, 100.0f,
                                      pitchCompOffsetCents + pitchCompSlopeCents * ((float) midiIdx - 60.0f)
                                      + noteOffsetsCents[(size_t) midiIdx]);
    const double pitchComp = std::pow (2.0, cents / 1200.0);
    currentFrequency = juce::MidiMessage::getMidiNoteInHertz (midiIdx) * pitchComp;
    setFrequency (currentFrequency);
    phase = 0.0f;
    updateParams();
    adsr.noteOn();
}

void FluteVoice::stopNote (float, bool allowTailOff)
{
    if (allowTailOff) adsr.noteOff();
    else { adsr.reset(); clearCurrentNote(); }
}

void FluteVoice::renderNextBlock (juce::AudioBuffer<float>& buffer, int startSample, int numSamples)
{
    if (! adsr.isActive()) { clearCurrentNote(); return; }

    updateParams();

    auto* left  = buffer.getWritePointer (0, startSample);
    auto* right = (buffer.getNumChannels() > 1) ? buffer.getWritePointer (1, startSample) : nullptr;

    for (int i = 0; i < numSamples; ++i)
    {
        const float sine   = std::sin (phase);
        const float saw    = 2.0f * (phaseOverPi - std::floor (phaseOverPi + 0.5f));
        const float square = (sine >= 0.0f ? 1.0f : -1.0f);

        float osc = sine * wSine + saw * wSaw + square * wSquare;

        if (preNoiseLin > 0.0f)
            osc += preNoiseLin * (randomUniform() * 2.0f - 1.0f);

        float filtered = DebugToggles::kEnableVaFilter ? svf.processSample (0, osc) : osc;

        float env = adsr.getNextSample();
        float y   = filtered * env * velocityGain;

        left[i] += y;
        if (right) right[i] += y;

        phase += phaseDelta;
        if (phase > juce::MathConstants<float>::twoPi)
            phase -= juce::MathConstants<float>::twoPi;
        phaseOverPi = phase / juce::MathConstants<float>::pi;
    }

    if (! adsr.isActive()) clearCurrentNote();
}

void FluteVoice::prepare (double sr, int samplesPerBlock, int /*numChannels*/)
{
    sampleRate = sr;
    adsr.setSampleRate (sr);

    juce::dsp::ProcessSpec spec;
    spec.sampleRate = sr;
    spec.maximumBlockSize = (juce::uint32) samplesPerBlock;
    spec.numChannels = 1; // voice is mono
    svf.reset();
    svf.prepare (spec);

    setFrequency (currentFrequency);
}

void FluteVoice::setFrequency (double hz)
{
    currentFrequency = hz * masterTuneFactor;
    phaseDelta = (float) (juce::MathConstants<double>::twoPi * currentFrequency / sampleRate);
}

float FluteVoice::randomUniform()
{
    rng = 1664525u * rng + 1013904223u;
    return (rng >> 8) * (1.0f / 16777216.0f);
}

void FluteVoice::updateParams()
{
    float s  = apvts.getRawParameterValue (ParamIDs::oscSine)->load();
    float sa = apvts.getRawParameterValue (ParamIDs::oscSaw)->load();
    float sq = apvts.getRawParameterValue (ParamIDs::oscSquare)->load();
    float sum = std::max (0.0001f, s + sa + sq);
    wSine = s / sum;  wSaw = sa / sum;  wSquare = sq / sum;

    juce::ADSR::Parameters p;
    p.attack  = apvts.getRawParameterValue (ParamIDs::attack)->load();
    p.decay   = apvts.getRawParameterValue (ParamIDs::decay)->load();
    p.sustain = apvts.getRawParameterValue (ParamIDs::sustain)->load();
    p.release = apvts.getRawParameterValue (ParamIDs::release)->load();
    adsr.setParameters (p);

    float cut = apvts.getRawParameterValue (ParamIDs::cutoff)->load();
    float res = apvts.getRawParameterValue (ParamIDs::resonance)->load();
    svf.setCutoffFrequency (cut);
    svf.setResonance (res);

    if (DebugToggles::kEnableNoiseDb)
    {
        float nDb = apvts.getRawParameterValue (ParamIDs::noiseDb)->load();
        preNoiseLin = juce::Decibels::decibelsToGain (nDb);
    }
    else
    {
        preNoiseLin = 0.0f;
    }
}

//==============================================================================
// PM (with amplitude ADSR)
void WaveguideFlute::prepare (double sr, int blockSize, int numCh)
{
    sampleRate = sr;
    (void) blockSize; (void) numCh;
    setFrequency (440.0);
    noiseGain = 0.02f;
    jetFeedback = 0.2f;
    dc.reset (sr);

    adsr.setSampleRate (sr);
    adsr.setParameters (envParams);
}

void WaveguideFlute::setFrequency (double hz)
{
    frequency = hz * masterTuneFactor;
    double lenSamples = sampleRate / frequency;
    int len = (int) juce::jmax (16.0, std::floor (lenSamples + 0.5));
    delay.setSize (1, len + 4);
    writePos = 0;
    for (int i = 0; i < delay.getNumSamples(); ++i) delay.setSample (0, i, 0.0f);
}

void WaveguideFlute::setEnvParams (float a, float d, float s, float r)
{
    envParams.attack  = juce::jmax (0.0f, a);
    envParams.decay   = juce::jmax (0.0f, d);
    envParams.sustain = s;
    envParams.release = juce::jmax (0.0f, r);
    baseRelease = envParams.release;
    adsr.setParameters (envParams);
}

void WaveguideFlute::setReleaseScale (float baseR, float scale)
{
    baseRelease = juce::jlimit (0.030f, 7.000f, baseR);
    envParams.release = juce::jlimit (0.030f, 7.000f, baseRelease * juce::jlimit (0.2f, 4.0f, scale));
    adsr.setParameters (envParams);
}

void WaveguideFlute::noteOn (int midi, float vel)
{
    const int midiIdx = juce::jlimit (0, 127, midi);
    const float v = juce::jlimit (0.0f, 1.0f, vel);
    // Velocity response: 24dB range with perceptual curve for expressive but audible dynamics
    const float velPerceptual = std::sqrt (v);
    velocityGain = juce::Decibels::decibelsToGain (juce::jmap (velPerceptual, 0.0f, 1.0f, -18.0f, 0.0f));
    const float cents = juce::jlimit (-100.0f, 100.0f,
                                      pitchCompOffsetCents + pitchCompSlopeCents * ((float) midiIdx - 60.0f)
                                      + noteOffsetsCents[(size_t) midiIdx]);
    const double pitchComp = std::pow (2.0, cents / 1200.0);
    setFrequency (juce::MidiMessage::getMidiNoteInHertz (midiIdx) * pitchComp);
    active = true;          // run the loop
    phase = 0.0f;
    adsr.noteOn();          // start amplitude envelope
}

void WaveguideFlute::noteOff()
{
    // Do not stop immediately; let ADSR release tail the sound.
    adsr.noteOff();
}

void WaveguideFlute::render (juce::AudioBuffer<float>& buffer, int start, int num)
{
    // If we are neither running nor have an active envelope, nothing to do
    if (!active && !adsr.isActive())
        return;

    auto* L = buffer.getWritePointer (0, start);
    auto* R = (buffer.getNumChannels() > 1 ? buffer.getWritePointer (1, start) : nullptr);

    for (int i = 0; i < num; ++i)
    {
        const int len = delay.getNumSamples();
        const int readPos = (writePos + 1) % len;
        float y = delay.getSample (0, readPos);

        // Jet nonlinearity (simple tanh) + weak noise excitation
        float breath = noiseGain * (randomUniform() * 2.0f - 1.0f);
        float jet = std::tanh (y * 1.6f + breath);

        // Feedback + loss
        float next = 0.996f * (jet * jetFeedback + y * (1.0f - jetFeedback));

        // DC-block
        if (DebugToggles::kEnablePmDcBlock)
            next = dc.process (next);

        // write back
        delay.setSample (0, writePos, next);
        writePos = (writePos + 1) % len;

        // Amplitude ADSR
        float env = adsr.getNextSample();
        float out = next * env * velocityGain;

        L[i] += out;
        if (R) R[i] += out;
    }

    // If envelope has fully finished, stop running the loop next time
    if (!adsr.isActive())
        active = false;
}

float WaveguideFlute::randomUniform()
{
    rng = 1664525u * rng + 1013904223u;
    return (rng >> 8) * (1.0f / 16777216.0f);
}

//==============================================================================
// pm2 stiff-string
// FIX #1 & #4: Removed static beginSharedBuses - buses now owned by processor and passed to voices

void Pm2StringBank::prepare (double sr, int blockSize, int numCh)
{
    sampleRate = sr;
    adsr.setSampleRate (sr);
    adsr.setParameters (envParams);
    postLpfEnv.setSampleRate (sr);
    postLpfEnv.setParameters (postLpfEnvParams);
    active = false;
    keyHeld = false;
    useReleaseLoopGain = false;
    releaseDelaySamples = 0;
    noteLifeSamples = 0;
    damperDelaySamples = 0;
    sustainPedalDown = false;
    loopEnergySmoothed = 0.0f;
    if (sampleRate > 0.0)
    {
        pedalChangeSamplesTotal = juce::jmax (1, (int) std::round (0.015 * sampleRate));
        pedalChangeSamplesRemaining = 0;
        pedalChangeFade = 1.0f;
        const float tauSamples = (float) (0.050 * sampleRate); // ~50ms smoothing
        loopEnergySmoothCoeff = tauSamples > 1.0f ? (1.0f - std::exp (-1.0f / tauSamples)) : 1.0f;
    }
    else
    {
        pedalChangeSamplesTotal = 0;
        pedalChangeSamplesRemaining = 0;
        pedalChangeFade = 1.0f;
        loopEnergySmoothCoeff = 1.0f;
    }
    const int maxDelayLen = juce::jmax (8, (int) std::ceil ((sampleRate / 20.0) + 4.0));
    for (auto& s : strings)
    {
        s.delay.clear();
        s.delay.reserve ((size_t) maxDelayLen);
        s.writePos = 0;
        s.delaySamples = 0.0;
        s.loopGain = 0.999f;
        s.baseGain = 1.0f;
        s.panGainL = 0.7071f;
        s.panGainR = 0.7071f;
        s.loopGainSmoothed = 0.999f;
        s.damperLossPrev = damper.lossOff;
        s.damperSoftenCountdown = 0;
        s.damperSoftenState = 0.0f;
        s.apStages = 1;
        s.dc.reset (sr);
        for (auto& ap : s.ap) ap = {};
        s.lpState = 0.0f;
        s.lpCoeff = 0.25f;
        s.interpAlpha = 0.0f;  // Thiran allpass interpolator coefficient
        s.interpZ1 = 0.0f;     // Thiran allpass interpolator state
        s.toneInjectSamplesLeft = 0;
        s.toneInjectPhase = 0.0f;
        s.toneInjectPhaseDelta = 0.0f;
        s.toneInjectGain = 0.0f;
        s.hammer = {};
        s.energyGainSmoothed = 1.0f;
        s.duplex.buf.clear();
        s.duplex.buf.reserve ((size_t) maxDelayLen);
        // Initialize fundamental resonator state (IMPROVEMENT 2)
        s.fundResonatorState1 = 0.0f;
        s.fundResonatorState2 = 0.0f;
        s.fundResonatorCoeff = 0.0f;
        s.fundResonatorGain = 0.0f;
    }

    juce::dsp::ProcessSpec spec { sr, (juce::uint32) blockSize, (juce::uint32) juce::jmax (1, numCh) };
    noteHpf.reset();
    noteHpf.prepare (spec);
    noteHpf.setType (juce::dsp::StateVariableTPTFilterType::highpass);
    noteHpf.setResonance (0.707f);
    noteHpfNumChannels = (int) spec.numChannels;
    auto prepBp = [&spec] (juce::dsp::StateVariableTPTFilter<float>& f)
    {
        f.reset();
        f.prepare (spec);
        f.setType (juce::dsp::StateVariableTPTFilterType::bandpass);
    };
    prepBp (couplingBpL);
    prepBp (couplingBpR);
    prepBp (sympBpL);
    prepBp (sympBpR);
    updateNoteHpf (currentMidiNote);
    lastOutL = 0.0f;
    lastOutR = 0.0f;
    postLpfStateL = 0.0f;
    postLpfStateR = 0.0f;
    
    // Initialize pink noise state (IMPROVEMENT 1)
    pinkNoiseState.fill (0.0f);
    pinkNoiseCounter = 0;
    
    // Initialize body resonance noise state (IMPROVEMENT 3)
    bodyNoiseState = 0.0f;
    bodyNoiseLp1 = 0.0f;
    bodyNoiseLp2 = 0.0f;
    bodyNoiseHp = 0.0f;
    bodyNoiseRng = 0x12345678;
}

void Pm2StringBank::setParams (const PresetModel::PmString& p)
{
    params = p;
}

void Pm2StringBank::setHammerParams (const PresetModel::HammerModel& h)
{
    hammer = h;
}

void Pm2StringBank::setFeltParams (const PresetModel::FeltModel& f)
{
    if (DebugToggles::kEnableFelt)
    {
        felt = f;
    }
    else
    {
        felt.preload = 0.0f;
        felt.stiffness = 1.0f;
        felt.hysteresis = 0.0f;
        felt.maxAmp = 10.0f;
    }
}

void Pm2StringBank::setDuplexParams (const PresetModel::Duplex& d)
{
    duplex = d;
}

void Pm2StringBank::setWdfParams (const PresetModel::WdfModel& w)
{
    wdf = w;
}

void Pm2StringBank::setCouplingParams (const PresetModel::Coupling& c)
{
    couplingGain = juce::jlimit (0.0f, 0.2f, c.gain);
    couplingQ    = juce::jlimit (0.2f, 5.0f, c.q);
    sympGain     = juce::jlimit (0.0f, 0.3f, c.sympGain);
    sympHighDamp = juce::jlimit (0.0f, 1.0f, c.sympHighDamp);
}

void Pm2StringBank::setDamperParams (const PresetModel::Damper& d)
{
    damper = d;
    float tauSamples = (float) (damper.smoothMs * 0.001 * sampleRate);
    damperSmoothCoeff = tauSamples > 1.0f ? (1.0f - std::exp (-1.0f / juce::jmax (1.0f, tauSamples))) : 1.0f;
    damperLiftSmoothCoeff = damperSmoothCoeff;
    damperSoftenSamples = (int) std::round (damper.softenMs * 0.001 * sampleRate);
    damperSoftenA = std::exp (-2.0f * juce::MathConstants<float>::pi * juce::jlimit (40.0f, 8000.0f, damper.softenHz) / (float) juce::jmax (20.0, sampleRate));
}

void Pm2StringBank::setDamperLift (float lift)
{
    damperLiftTarget = juce::jlimit (0.0f, 1.0f, lift);
}

void Pm2StringBank::beginVoiceStealFade (float ms)
{
    const float clampedMs = juce::jlimit (2.0f, 80.0f, ms);
    stealFadeSamples = juce::jmax (1, (int) std::round (clampedMs * 0.001f * sampleRate));
    stealFadeRemaining = stealFadeSamples;
}

void Pm2StringBank::setSoftPedal (bool down, const PresetModel::UnaCorda& una)
{
    softPedalDown = down;
    unaCorda = una;
}

void Pm2StringBank::setSustainPedalDown (bool down)
{
    if (sustainPedalDown != down)
    {
        if (pedalChangeSamplesTotal <= 0 && sampleRate > 0.0)
            pedalChangeSamplesTotal = juce::jmax (1, (int) std::round (0.015 * sampleRate));
        pedalChangeSamplesRemaining = pedalChangeSamplesTotal;
        pedalChangeFade = 0.0f;
    }
    sustainPedalDown = down;
    if (! sustainPedalDown && ! keyHeld)
    {
        useReleaseLoopGain = true;
        adsr.noteOff();
        postLpfEnv.noteOff();
    }
}

void Pm2StringBank::setEnvParams (float attack, float decay, float sustain, float release)
{
    envParams.attack  = juce::jmax (0.0f, attack);
    envParams.decay   = juce::jmax (0.0f, decay);
    envParams.sustain = sustain;
    envParams.release = juce::jmax (0.0f, release);
    baseRelease = envParams.release;
    adsr.setParameters (envParams);
    
    // Store decay for influencing physical model T60
    // Use the provided decay directly (no clamp) to scale T60.
    if (envParams.decay > 0.0f)
        decayTimeScale = juce::jlimit (0.5f, 1.5f, envParams.decay / 2.0f);
    else
        decayTimeScale = 0.0f;
}

void Pm2StringBank::setReleaseScale (float baseR, float scale)
{
    baseRelease = juce::jlimit (0.030f, 7.000f, baseR);
    envParams.release = juce::jlimit (0.030f, 7.000f, baseRelease * juce::jlimit (0.2f, 4.0f, scale));
    adsr.setParameters (envParams);
}

void Pm2StringBank::updateNoteHpf (int midiNoteNumber)
{
    if (sampleRate <= 0.0)
        return;

    const float note = (float) juce::jlimit (0, 127, midiNoteNumber);
    const float norm = juce::jlimit (0.0f, 1.0f, (note - 21.0f) / (108.0f - 21.0f));
    const float eased = std::pow (norm, 1.5f);
    noteHpfCutoff = juce::jlimit (30.0f, 70.0f, 30.0f + eased * (70.0f - 30.0f));
    noteHpf.setCutoffFrequency (noteHpfCutoff);
}

void Pm2StringBank::resizeString (StringState& s, double samples)
{
    const int len = juce::jmax (8, (int) std::ceil (samples + 4.0));
    s.delay.resize ((size_t) len);
    std::fill (s.delay.begin(), s.delay.end(), 0.0f);
    s.writePos = 0;
    s.delaySamples = samples;
    // FIX #5: Removed dc.reset() - resetting the DC blocker on every note-on
    // causes clicks when there's residual DC offset being filtered.
    // DC blocker state is now only reset in prepare().
    
    // Thiran allpass interpolator coefficient for fractional delay
    // Formula: alpha = (1 - d) / (1 + d) where d is fractional delay in (0, 1)
    const double intPart = std::floor (samples);
    double frac = samples - intPart;
    // Ensure frac is in valid range for stable allpass (avoid d=0 or d=1)
    frac = juce::jlimit (0.1, 0.9, frac);
    s.interpAlpha = (float) ((1.0 - frac) / (1.0 + frac));
    s.interpZ1 = 0.0f;  // Reset interpolator state
}

static inline float mixLinear (float a, float b, float t)
{
    return a * (1.0f - t) + b * t;
}

static inline float softClip (float x, float limit)
{
    if (! DebugToggles::kEnablePm2SoftClip)
        return x;
    const float safeLimit = juce::jmax (1.0e-6f, limit);
    return safeLimit * FastMath::fastTanh (x / safeLimit);
}

static PresetModel::WdfModel sanitizeWdf (PresetModel::WdfModel w)
{
    auto c = PresetModel::clamp;
    auto finiteOr = [] (float v, float fallback) { return std::isfinite (v) ? v : fallback; };
    w.enabled = w.enabled;
    w.blend = c (finiteOr (w.blend, 0.0f), 0.0f, 1.0f);
    w.loss  = c (finiteOr (w.loss, 0.0f),  0.0f, 0.1f);
    w.bridgeMass = c (finiteOr (w.bridgeMass, 1.0f), 0.1f, 10.0f);
    w.plateStiffness = c (finiteOr (w.plateStiffness, 1.0f), 0.1f, 5.0f);
    return w;
}

// Lightweight WDF-ish burst generator (offline prototype port)
static std::vector<float> buildWdfBurst (double sampleRate,
                                         double baseHz,
                                         float velocity,
                                         int totalExcite,
                                         float loss,
                                         float bridgeMass,
                                         float plateStiffness,
                                         uint32_t& rng)
{
    std::vector<float> out ((size_t) juce::jmax (1, totalExcite), 0.0f);
    if (! std::isfinite (sampleRate) || sampleRate <= 0.0 || ! std::isfinite (baseHz) || baseHz <= 0.0f)
        return out;

    const double delaySamples = sampleRate / juce::jmax (20.0, baseHz);
    const int delayLen = juce::jmax (8, (int) std::ceil (delaySamples));
    std::vector<float> delay ((size_t) delayLen, 0.0f);
    int write = 0;
    const float frac = (float) (delaySamples - std::floor (delaySamples));

    const float loopLoss = juce::jlimit (0.0f, 0.1f, loss);
    const float loopGain = std::exp (-loopLoss);
    float lpState = 0.0f;
    const float lpCoeff = 0.25f;

    auto rand01 = [&rng]() -> float
    {
        rng = 1664525u * rng + 1013904223u;
        return (float) ((rng >> 8) * (1.0 / 16777216.0)); // [0..1)
    };

    const float R_h = 1.0f;
    const float R_s = 1.0f + loopLoss * 10.0f;
    const float R_b = juce::jlimit (0.05f, 10.0f, bridgeMass);
    float bx = 0.0f, bv = 0.0f;
    const float mass = juce::jmax (0.05f, bridgeMass);
    const float stiff = juce::jmax (0.1f, plateStiffness);
    const float damp = loopLoss * 20.0f;

    const float preload = 0.08f;
    const float stiffness = 2.4f;
    const float hysteresis = 0.15f;
    const float feltMax = 1.4f;
    const float maxDelta = feltMax * 0.5f;
    float feltState = 0.0f;

    const int attack = juce::jmax (1, (int) std::round (0.006 * sampleRate));
    const int decay  = juce::jmax (1, (int) std::round (0.010 * sampleRate));
    const int release= juce::jmax (1, (int) std::round (0.006 * sampleRate));

    auto delayRead = [&delay, delayLen](int idx, float fracPart) -> float
    {
        const int i0 = (idx + delayLen) % delayLen;
        const int i1 = (i0 + 1) % delayLen;
        return delay[(size_t) i0] * (1.0f - fracPart) + delay[(size_t) i1] * fracPart;
    };

    for (int n = 0; n < (int) out.size(); ++n)
    {
        float env = 0.0f;
        if (n < attack) env = (float) n / (float) attack;
        else if (n < attack + decay)
        {
            const float t = (float) (n - attack) / (float) decay;
            env = 1.0f - 0.9f * t;
        }
        else if (n < attack + decay + release)
        {
            const float t = (float) (n - attack - decay) / (float) release;
            env = juce::jmax (0.0f, 0.1f * (1.0f - t));
        }

        // hammer noise
        float noise = (rand01() * 2.0f - 1.0f) * env * std::pow (juce::jlimit (0.0f, 1.0f, velocity), 1.2f);

        // felt-ish shaping
        float mag = std::pow (preload + std::abs (noise), stiffness) - std::pow (preload, stiffness);
        float shaped = (1.0f - hysteresis) * mag + hysteresis * feltState;
        feltState = shaped;
        float feltOut = softClip ((float) std::copysign (shaped, noise), feltMax);
        float delta = feltOut - feltState;
        delta = softClip (delta, maxDelta);
        feltOut = feltState + delta;

        float a_h = feltOut * R_h;
        float a_s = delayRead (write, frac);
        float a_b = bx; // displacement proxy

        const float denom = (1.0f / R_h) + (1.0f / R_s) + (1.0f / R_b);
        const float Vj = (a_h / R_h + a_s / R_s + a_b / R_b) / juce::jmax (1.0e-6f, denom);
        const float b_h = 2.0f * Vj - a_h;
        const float b_s = 2.0f * Vj - a_s;
        const float b_b = 2.0f * Vj - a_b;
        (void) b_h; // reserved for future refinement

        // bridge integrator (semi-implicit)
        float drive = (b_b - a_b) * 0.5f / juce::jmax (1.0e-6f, R_b);
        float dt = 1.0f / (float) sampleRate;
        float acc = (drive - stiff * bx - damp * bv) / juce::jmax (0.05f, mass);
        bv = softClip (bv + dt * acc, 20.0f);
        bx = softClip (bx + dt * bv, 5.0f);

        // loop
        lpState = lpState + lpCoeff * (b_s - lpState);
        float loopSample = lpState * loopGain;
        delay[(size_t) write] = loopSample;
        write = (write + 1) % delayLen;

        float mixed = mixLinear (b_s * 0.5f + a_s * 0.5f, bx * 0.5f, 0.4f);
        if (! std::isfinite (mixed))
            mixed = 0.0f;
        out[(size_t) n] = softClip (mixed, 2.0f);
    }

    return out;
}

void Pm2StringBank::noteOn (int midiNoteNumber, float velocity)
{
    keyHeld = true;
    keyReleaseSamplesRemaining = 0;
    keyOffFadeSamplesRemaining = 0;
    pendingNoteOff = false;
    minNoteOffRemaining = minNoteDurationSamples;
    currentMidiNote = midiNoteNumber;
    useReleaseLoopGain = false;
    loopEnergySmoothed = 0.0f;
    // If this voice was previously stolen, cancel any pending steal fade.
    stealFadeRemaining = 0;
    stealFadeSamples = 0;
    stealInProgress = false;
    updateNoteHpf (midiNoteNumber);
    damperLiftSmoothed = damperLiftTarget;
    
    // CPU OPTIMIZATION: String count varies by register for CPU efficiency
    // - Treble (>= C7/96): 2 strings (real pianos use 2-3, less difference audible)
    // - Bass gradual fade: G2 down to D#2, third string fades from 80% to 0%
    // - Deep bass (<= D#2/39): 2 strings only
    // - Mid range: Full 3 strings for rich chorus effect
    const int trebleSplitNote = 96;   // C7 - use 2 strings above this
    const int bassFadeStartNote = 43; // G2 - third string at 80%
    const int bassFadeEndNote = 36;   // C2 - switch to 2 strings at and below this
    
    // Calculate third string gain scale for bass notes (1.0 = full, 0.0 = muted)
    // Gradual fade: G2=0.8, F#2=0.6, F2=0.4, E2=0.2, D#2=0.0, etc.
    if (midiNoteNumber >= trebleSplitNote)
    {
        currentNumStrings = 2;
        thirdStringGainScale = 0.0f;
    }
    else if (midiNoteNumber > bassFadeStartNote)
    {
        // Above G2: full third string
        currentNumStrings = 3;
        thirdStringGainScale = 1.0f;
    }
    else if (midiNoteNumber <= bassFadeEndNote)
    {
        // C2 and below: use only 2 strings
        currentNumStrings = 2;
        thirdStringGainScale = 0.0f;
    }
    else
    {
        // Gradual fade zone from G2 (43) down to C#2 (37)
        // G2=43 -> 0.80, F#2=42 -> 0.60, F2=41 -> 0.40, E2=40 -> 0.20
        // D#2=39 -> 0.0 (effectively 2 strings), D2=38 -> 0.0, C#2=37 -> 0.0
        currentNumStrings = 3;  // Keep 3 strings for smooth crossfade
        const float fadeRange = (float) (bassFadeStartNote - bassFadeEndNote);  // 43-36 = 7 semitones
        const float notePos = (float) (midiNoteNumber - bassFadeEndNote);       // Position in fade zone
        // Scale so G2 (43) = 0.8 and C#2 (37) = ~0.0
        thirdStringGainScale = juce::jlimit (0.0f, 0.8f, (notePos / fadeRange) * 0.8f);
        
        // If gain is very small, use 2 strings to save CPU
        if (thirdStringGainScale < 0.05f)
        {
            currentNumStrings = 2;
            thirdStringGainScale = 0.0f;
        }
    }

    const int midiIdx = juce::jlimit (0, 127, midiNoteNumber);
    const float pitchCents = juce::jlimit (-100.0f, 100.0f,
                                           pitchCompOffsetCents + pitchCompSlopeCents * ((float) midiIdx - 60.0f)
                                           + noteOffsetsCents[(size_t) midiIdx]);
    const double pitchComp = std::pow (2.0, pitchCents / 1200.0);
    const double baseHz = juce::MidiMessage::getMidiNoteInHertz (midiIdx) * pitchComp * masterTuneFactor;
    const float v = juce::jlimit (0.0f, 1.0f, velocity);
    if (v < 0.4f)
        lowVelSkip = (randomUniform() < 0.25f);
    else
        lowVelSkip = false;
    // Velocity response with moderate dynamic range:
    // - 24dB range keeps soft notes audible while still expressive
    // - Applied perceptual curve (sqrt) so velocity feels more natural to play
    const float velPerceptual = std::sqrt (v);
    velocityGain = juce::Decibels::decibelsToGain (juce::jmap (velPerceptual, 0.0f, 1.0f, -18.0f, 0.0f));
    if (PhysicsToggles::kUsePerNotePhysics)
    {
        const int midiVel = juce::jlimit (0, 127, (int) std::round (v * 127.0f));
        const float hammerVel = PianoPhysics::Velocity::midiToHammerVelocity (midiVel);
        const float brightnessTilt = juce::jlimit (0.0f, 1.0f, PianoPhysics::Velocity::getBrightnessTilt (hammerVel));
        const float minHzBase = (float) baseHz * 1.5f;
        const float maxHzBase = (float) baseHz * (4.0f + 6.0f * brightnessTilt);
        float minHz = juce::jlimit (500.0f, 6000.0f, minHzBase);
        float maxHz = juce::jlimit (2500.0f, 16000.0f, maxHzBase);
        if (sustainPedalDown)
        {
            minHz *= 1.45f;
            maxHz *= 1.35f;
        }
        postLpfMinHz = juce::jlimit (500.0f, 8000.0f, minHz);
        postLpfMaxHz = juce::jlimit (2500.0f, 18000.0f, maxHz);

        const float t60 = PianoPhysics::StringDecay::getT60 ((float) baseHz, midiNoteNumber);
        const float brightDecay = juce::jlimit (0.10f, 1.4f, t60 * 0.05f);
        const float brightRelease = juce::jlimit (0.08f, 1.0f, brightDecay * 0.70f);
        postLpfEnvParams.attack  = 0.003f;
        postLpfEnvParams.decay   = brightDecay;
        float sustain = juce::jlimit (0.08f, 0.35f, 0.12f + 0.18f * brightnessTilt);
        if (sustainPedalDown)
            sustain = juce::jlimit (0.15f, 0.60f, sustain + 0.14f);
        postLpfEnvParams.sustain = sustain;
        postLpfEnvParams.release = brightRelease;
        postLpfEnv.setParameters (postLpfEnvParams);
    }
    noteFadeSamplesTotal = juce::jmax (1, (int) std::round (0.001 * sampleRate));
    noteFadeSamplesRemaining = noteFadeSamplesTotal;
    postLpfEnv.noteOn();
    postLpfStateL = 0.0f;
    postLpfStateR = 0.0f;
    const float bpFreq = juce::jlimit (60.0f, 6000.0f, (float) baseHz * 1.1f);
    couplingBpL.setCutoffFrequency (bpFreq);
    couplingBpR.setCutoffFrequency (bpFreq);
    couplingBpL.setResonance (couplingQ);
    couplingBpR.setResonance (couplingQ);
    sympBpL.setCutoffFrequency (bpFreq);
    sympBpR.setCutoffFrequency (bpFreq);
    sympBpL.setResonance (juce::jmax (0.3f, couplingQ * 0.8f));
    sympBpR.setResonance (juce::jmax (0.3f, couplingQ * 0.8f));
    // Lift velocity curve: 35% minimum excitation floor ensures soft notes have enough energy
    // to properly excite the string model, while velocityGain handles actual loudness dynamics
    const float velCurveRaw = std::pow (v, juce::jlimit (0.6f, 2.5f, hammer.gamma));
    const float velCurve = 0.35f + 0.65f * velCurveRaw;  // 35% floor, scales to 100%
    const float stiffnessScale = juce::jlimit (0.4f, 2.5f, 1.0f + hammer.stiffnessVelScale * (velCurve - 0.5f) * 2.0f);
    const float preloadScale   = juce::jlimit (0.3f, 2.5f, 1.0f + hammer.preloadVelScale   * (velCurve - 0.5f) * 2.0f);
    const float toneScale      = juce::jlimit (0.5f, 2.0f, 1.0f + hammer.toneVelScale      * (velCurve - 0.5f) * 2.0f);
    const float toneHzEff      = juce::jlimit (hammer.toneMinHz, hammer.toneMaxHz, hammer.toneHz * toneScale);
    float contactScale = 1.0f;
    if (PhysicsToggles::kUsePerNotePhysics)
    {
        const float exp = PianoPhysics::Hammer::getExponent (midiNoteNumber);
        contactScale = juce::jlimit (0.6f, 1.4f, PianoPhysics::Hammer::getContactDurationScale (v, exp));
    }
    const int hammerWindowSamples = juce::jmax (1, (int) std::round (juce::jlimit (5.0f, 45.0f, hammer.attackWindowMs * contactScale) * 0.001 * sampleRate));
    {
        const float semisFrom60 = (float) midiNoteNumber - 60.0f;
        // FIXED: Allow larger negative slopes for realistic treble attenuation
        float slopeDbPerSemi = juce::jlimit (-0.25f, 0.1f, loudnessSlopeDbPerSemi);
        slopeDbPerSemi *= 0.95f; // slightly lighter pitch-dependent attenuation
        if (sustainPedalDown)
            slopeDbPerSemi *= 0.85f; // slightly lighter sustain-dependent reduction
        // FIXED: Tighter limits - prevent extreme boosts, allow more attenuation for treble
        pitchLoudnessGain = juce::jlimit (0.6f, 1.25f,
                                          juce::Decibels::decibelsToGain (semisFrom60 * slopeDbPerSemi));
    }

    // Frequency-dependent loop loss scalar (no filter in loop)
    {
        const float noteNorm = juce::jlimit (0.0f, 1.0f, ((float) midiNoteNumber - 21.0f) / (108.0f - 21.0f));
        const float curve = noteNorm * noteNorm;
        float maxLoss = 0.004f; // mild high-note darkening without filter in loop
        if (PhysicsToggles::kUsePerNotePhysics && sustainPedalDown)
            maxLoss = 0.002f;
        freqLossScalar = juce::jlimit (0.98f, 1.0f, 1.0f - maxLoss * curve);
        // Compensate for higher loop rates so treble notes aren't over-damped.
        const float lossComp = juce::jlimit (0.0f, 1.0f, (noteNorm - 0.55f) / 0.45f);
        freqLossScalar = mixLinear (freqLossScalar, 1.0f, 0.65f * lossComp);
    }

    // Note-dependent stereo width: bass wide, treble narrow
    const float noteForWidth = (float) midiNoteNumber;
    const float widthPos = juce::jlimit (0.0f, 1.0f,
                                         (noteForWidth - params.stereoWidthNoteLo)
                                         / juce::jmax (1.0f, params.stereoWidthNoteHi - params.stereoWidthNoteLo));
    stereoWidth = mixLinear (params.stereoWidthLow, params.stereoWidthHigh, widthPos);

    // FIXED: Calculate normalization factor for multi-string summing
        // Sum the gains of all active strings and normalize so total energy stays consistent
        {
            float gainSum = 0.0f;
            for (int i = 0; i < currentNumStrings; ++i)
                gainSum += params.gain[(size_t) i];
        // Use sqrt for energy-based normalization (not amplitude-based)
        // This prevents level buildup when multiple strings are summed
        const float rawNorm = (gainSum > 0.001f) ? (1.0f / std::sqrt (gainSum)) : 1.0f;
        stringGainNorm = mixLinear (1.0f, rawNorm, 0.6f);
        }

    for (int i = 0; i < currentNumStrings; ++i)
    {
        float detune = params.detuneCents[(size_t) i];
        if (softPedalDown)
            detune += unaCorda.detuneCents;
        double hz = baseHz * std::pow (2.0, detune / 1200.0);
        double targetDelay = sampleRate / juce::jmax (20.0, hz);
        
        // Inharmonicity-driven dispersion for physical realism.
        float g = 0.0f;
        if (PhysicsToggles::kUsePerNotePhysics)
        {
            const float bCoeff = PianoPhysics::Inharmonicity::getB (midiNoteNumber);
            g = mapInharmonicityToDispersion (bCoeff, params.dispersionAmt);
        }
        else
        {
            // Heuristic dispersion curve (legacy).
            const float noteNormDisp = juce::jlimit (0.0f, 1.0f, ((float) midiNoteNumber - 21.0f) / (108.0f - 21.0f));
            const float bassInharm = std::pow (juce::jmax (0.0f, 1.0f - noteNormDisp * 1.3f), 1.4f);
            const float trebleOnset = 0.72f;  // ~C6
            const float trebleInharm = (noteNormDisp > trebleOnset)
                ? std::pow ((noteNormDisp - trebleOnset) / (1.0f - trebleOnset), 1.8f) * 0.25f
                : 0.0f;
            const float inharmCurve = bassInharm + trebleInharm;
            g = juce::jlimit (0.0f, 0.40f, params.dispersionAmt * inharmCurve);
        }
        
        // Additional frequency scaling for very low notes (more dispersion needed)
        const float freqScale = juce::jlimit (0.7f, 1.2f, 1.0f + 0.2f * (1.0f - juce::jmin (1.0f, (float) hz / 200.0f)));
        g *= freqScale;
        
        if (! DebugToggles::kEnablePm2Dispersion)
            g = 0.0f;
        if (highPolyMode)
            g *= 0.4f;
            
        // Gentler taper for mid-high frequencies (was too aggressive)
        float taper = (float) (1.0 - 0.20 * juce::jlimit (0.0, 1.0, (hz - 600.0) / 2200.0));
        const float noteNormDisp = juce::jlimit (0.0f, 1.0f, ((float) midiNoteNumber - 21.0f) / (108.0f - 21.0f));
        const float dispScale = mixLinear (1.0f, dispersionHighMult, std::pow (noteNormDisp, dispersionPow));
        float gScaled = juce::jlimit (0.0f, 0.50f, g * taper * dispScale);
        const float dispTrebleComp = 1.0f - 0.35f * juce::jlimit (0.0f, 1.0f, ((float) midiNoteNumber - 72.0f) / 36.0f);
        gScaled *= dispTrebleComp;
        if (! DebugToggles::kEnablePm2Dispersion)
            gScaled = 0.0f;
        
        // FIX: Smooth transition of allpass stages instead of hard cutoffs at specific notes
        // Previously had abrupt changes at notes 76, 84, 88 causing audible discontinuities
        int apStagesEffective = juce::jlimit (1, 4, params.apStages);
        // Gradual reduction from note 72 to 96 (C5 to C7)
        const float apFadeNorm = juce::jlimit (0.0f, 1.0f, ((float) currentMidiNote - 72.0f) / 24.0f);
        if (apFadeNorm > 0.0f)
        {
            // Smoothly reduce stages: 4->3 by note 80, 3->2 by note 88, 2->1 by note 96
            const float targetStages = 4.0f - apFadeNorm * 3.0f;
            apStagesEffective = juce::jmax (1, (int) std::round (targetStages));
        }
        if (economyMode && currentMidiNote > 72)
            apStagesEffective = juce::jmin (apStagesEffective, 2);
        if (economyMode && currentMidiNote > 84)
            apStagesEffective = 1;
        if (highPolyMode)
            apStagesEffective = 1;
        if (! DebugToggles::kEnablePm2Dispersion)
            apStagesEffective = 0;

        // Improved group delay compensation:
        // - Use 0.92 factor (was 0.55) to better match actual allpass delay
        // - Add frequency-dependent correction for higher notes
        const float baseCompensation = 0.92f;
        const float freqCorrection = 1.0f + 0.08f * juce::jlimit (0.0f, 1.0f, (float)(hz - 200.0) / 2000.0f);
        float groupDelay = (apStagesEffective > 0 && gScaled > 0.0f)
                               ? baseCompensation * freqCorrection * (float) apStagesEffective * (1.0f - gScaled) / (1.0f + gScaled)
                               : 0.0f;
        double delaySamples = juce::jmax (8.0, targetDelay - (double) groupDelay);
        auto& s = strings[(size_t) i];
        resizeString (s, delaySamples);
        // Option 1: Initialize energy limiter - calibration window captures peak during first 100ms
        const int calibrationMs = 200;
        s.energyCalibSamplesLeft = (int) (sampleRate * calibrationMs / 1000.0);
        s.energyCalibComplete = false;
        s.energyPeak = 0.0f;
        s.energySmoothed = 0.0f;
        s.energyGainSmoothed = 1.0f;

        // ====================================================================
        // FREQUENCY-NORMALIZED LOSS MODEL - REALISTIC PIANO SUSTAIN
        // A real grand piano has very long sustain times:
        // - Low notes (C1-C2): 25-40 seconds
        // - Mid notes (C3-C4): 18-25 seconds  
        // - High notes (C6-C7): 12-18 seconds
        // The GUI Decay control scales this via decayTimeScale.
        // ====================================================================

        // Base T60 varies with pitch - lower notes sustain longer (like a real piano)
        // Reference: A4 (440 Hz, MIDI 69) gets base T60 of ~22 seconds
        const float midiNote = 12.0f * std::log2 ((float) hz / 440.0f) + 69.0f;
        const float noteNorm = juce::jlimit (0.0f, 1.0f, (midiNote - 21.0f) / 87.0f); // A0 to C8

        float pitchBasedT60 = 0.0f;
        if (PhysicsToggles::kUsePerNotePhysics)
        {
            pitchBasedT60 = PianoPhysics::StringDecay::getT60 ((float) hz, midiNoteNumber);
        }
        else
        {
            // FIX: Further increased highT60 from 16s to 22s for much longer treble sustain
            // Using an even gentler curve (power of 0.5) so mid/high notes keep most of their sustain
            // Low notes: ~28s, Mid notes: ~24s, High notes: ~22s (much more even distribution)
            const float lowT60 = 28.0f;   // Increased from 26
            const float highT60 = 24.0f;  // Smaller low/high spread for less pitch-dependent decay
            // Use a very gentle curve - high notes should only lose ~20% of low note sustain
            const float curvedNoteNorm = std::pow (noteNorm, 0.5f);  // Even gentler curve (was 0.7)
            pitchBasedT60 = lowT60 - curvedNoteNorm * (lowT60 - highT60);
        }
        
        // Apply loss parameter and GUI decay control
        const float effectiveLoss = juce::jmax (0.0025f, params.loss);
        const float lossNorm = juce::jlimit (0.0f, 1.0f, (effectiveLoss - 0.0005f) / (0.02f - 0.0005f));
        float lossEffect = 1.0f - 0.3f * lossNorm; // Reduced from 0.4 - loss has less impact now
        if (PhysicsToggles::kUsePhysicsDefaults)
            lossEffect = 1.0f;
        float targetT60_s = pitchBasedT60 * lossEffect * decayTimeScale;
        // Global sustain scaler - reduced from 1.50 to shorten note duration slightly
        const float globalT60Scale = 1.15f;  // Was 1.50f - notes were sustaining too long
        targetT60_s *= globalT60Scale;
        if (PhysicsToggles::kUsePhysicsDefaults)
            targetT60_s = juce::jmax (6.0f, targetT60_s);  // Was 12.0f - reduced minimum sustain
        // Extra treble sustain to avoid high-note truncation (applies above C5).
        if (DebugToggles::kEnablePm2TrebleT60Boost)
        {
            const float trebleNorm = juce::jlimit (0.0f, 1.0f, ((float) midiNoteNumber - 72.0f) / 36.0f);
            const float trebleT60Boost = 1.0f + 1.05f * trebleNorm; // up to +105% at C8
            targetT60_s *= trebleT60Boost;
        }

        // Calculate loops per second for this string
        const float loopsPerSecond = (float) hz;

        // Total loops during the target T60 period
        const float totalLoopsInT60 = targetT60_s * loopsPerSecond;

        // For T60 (60 dB decay), we need: loopGain^totalLoopsInT60 = 10^(-60/20) = 0.001
        // So: loopGain = 0.001^(1/totalLoopsInT60) = exp(ln(0.001)/totalLoopsInT60)
        // ln(0.001) ≈ -6.9078
        float loopGainCalc = std::exp (-6.9078f / juce::jmax (1.0f, totalLoopsInT60));
        if (PhysicsToggles::kUsePhysicsDefaults)
            loopGainCalc = juce::jlimit (0.98f, 0.99999f, loopGainCalc);
        
        // FIX: Add a small pitch-dependent boost to loop gain for higher notes
        // This compensates for the cumulative effect of per-loop filtering at high frequencies
        if (DebugToggles::kEnablePm2TrebleLoopGainBoost)
        {
            const float trebleBoostStart = 60.0f;  // Start boosting above middle C
            const float trebleBoostAmount = 0.0001f * juce::jmax (0.0f, midiNote - trebleBoostStart);
            loopGainCalc = juce::jlimit (0.95f, 0.99999f, loopGainCalc + trebleBoostAmount);
        }
        // Extra high-note loop gain to counter per-loop filtering compounding.
        if (DebugToggles::kEnablePm2TrebleLoopGainComp)
        {
            const float loopGainComp = 0.00024f * juce::jlimit (0.0f, 1.0f, (midiNote - 72.0f) / 36.0f);
            loopGainCalc = juce::jlimit (0.95f, 0.99999f, loopGainCalc + loopGainComp);
        }
        
        s.loopGainBase = loopGainCalc;
        
        s.loopGainRelease = juce::jlimit (0.90f, 0.99999f, s.loopGainBase * juce::jlimit (1.0f, 4.0f, releaseExtension));
        s.loopGain = s.loopGainBase;
        s.loopGainSmoothed = s.loopGainBase;
        s.damperLossPrev = damper.lossOff;
        s.damperLossSmoothed = damper.lossOff;
        s.damperSoftenCountdown = 0;
        s.damperSoftenState = 0.0f;

        // LPF coefficient: frequency-normalized for consistent tone across the keyboard
        // FIX: Made filter much gentler for high notes to preserve sustain
        // High notes iterate through the loop many more times per second, so aggressive
        // filtering compounds quickly and kills the sound
        const float refHz = 440.0f;
        const float freqRatio = refHz / juce::jmax (20.0f, (float) hz);
        // IMPROVEMENT 4: Gentler high-frequency rolloff for more realistic harmonic content
        // Real piano strings have a gradual high-frequency decay, not aggressive filtering
        // Higher baseLpCoeff = less filtering per sample = more upper harmonics preserved
        const float baseLpCoeff = 0.92f;  // Increased from 0.88 for more HF content
        
        // Gentler frequency compensation: high notes need much less filtering
        // because they iterate through the loop many more times per second
        const float freqCompensation = 1.0f / juce::jmax (0.75f, std::pow (freqRatio, 0.08f));
        
        // Velocity-dependent brightness: harder hits = brighter tone (more upper harmonics)
        // This simulates how harder hammer strikes excite more high-frequency content
        const float velBrightness = 1.0f + 0.025f * (velCurve - 0.5f);
        
        const float lpTrebleComp = 1.0f + 0.08f * juce::jlimit (0.0f, 1.0f, (midiNote - 72.0f) / 36.0f);
        s.lpCoeff = juce::jlimit (0.82f, 0.998f, baseLpCoeff * freqCompensation * velBrightness * lpTrebleComp);
        s.lpState = 0.0f;

        // dispersion allpass coefficient scaled by dispersionAmt and pitch
        // reuse g
        s.apStages = apStagesEffective;
        for (int k = 0; k < s.apStages; ++k) { s.ap[(size_t) k].g = gScaled; s.ap[(size_t) k].z1 = 0.0f; }
        for (int k = s.apStages; k < 4; ++k) { s.ap[(size_t) k].g = 0.0f; s.ap[(size_t) k].z1 = 0.0f; }

        // Hammer excitation: either continuous interaction or simplified burst
        const float refDelaySamples = 100.0f;
        const float actualDelaySamples = (float) s.delay.size();
        // FIX: Made high note attenuation much gentler - was pow(..., 0.4) which cut high notes to ~50%
        // Now using pow(..., 0.2) so high notes retain ~75% of excitation energy
        const float highNoteAtten = std::pow (juce::jmin (1.0f, actualDelaySamples / refDelaySamples), 0.01f);
        float exciteGain = juce::jlimit (0.0f, 1.4f, hammer.force * velCurve * highNoteAtten);  // Reduced limit from 1.8
        if (PhysicsToggles::kUsePhysicsDefaults)
            exciteGain *= 0.85f;  // Was 1.2f - reduced to lower overall levels
        // Normalize excitation across the keyboard so hard notes land closer in level.
        const float noteNormExcite = juce::jlimit (0.0f, 1.0f, ((float) midiNoteNumber - 21.0f) / (108.0f - 21.0f));
        const float exciteNorm = 1.10f - 0.20f * noteNormExcite; // gentle high-note reduction only
        exciteGain = juce::jlimit (0.0f, 1.8f, exciteGain * exciteNorm);
        // Ensure all notes retain a minimum excitation floor for audible transient
        // Reduced from 0.22f base to lower overall levels
        const float noteNormFloor = juce::jlimit (0.0f, 1.0f, (midiNoteNumber - 21.0f) / 87.0f);
        const float exciteFloor = 0.15f + 0.08f * noteNormFloor;  // Was 0.22f + 0.10f
        exciteGain = juce::jmax (exciteGain, exciteFloor);
        if (PhysicsToggles::kUsePhysicsDefaults)
        {
            const float toneHz = (float) (sampleRate / juce::jmax (8.0, delaySamples));
            s.toneInjectPhase = 0.0f;
            s.toneInjectPhaseDelta = juce::MathConstants<float>::twoPi * toneHz / (float) sampleRate;
            s.toneInjectSamplesLeft = (int) std::round (0.015f * sampleRate);  // Reduced from 0.020
            s.toneInjectGain = 0.12f * exciteGain;  // Reduced from 0.20f
        }
        
        const float attackMs = juce::jlimit (1.0f, 12.0f, hammer.attackMs * contactScale);
        const float timeScale = juce::jlimit (0.95f, 1.0f,
                                              std::pow (actualDelaySamples / refDelaySamples, 0.25f)); // gentler treble shortening
        const int attackSamples  = juce::jmax (1, (int) std::round (attackMs * 0.001 * sampleRate * timeScale));
        const int decaySamples   = juce::jmax (1, (int) std::round (0.012 * sampleRate * timeScale));
        const int releaseSamples = juce::jmax (1, (int) std::round (0.005 * sampleRate * timeScale));
        juce::ignoreUnused (releaseSamples);
        
        const int minExciteSamples = (int) std::round (0.18 * sampleRate); // ensure audible transient on high notes
        const int totalExcite = juce::jmax ((int) s.delay.size(), minExciteSamples);

        // IMPROVEMENT 7: Velocity-Dependent Harmonic Content
        // Real pianos produce different harmonic spectra at different velocities
        // Soft hits: darker tone, fewer upper partials (felt absorbs high frequencies)
        // Hard hits: brighter tone, more upper partials (felt compresses, acts harder)
        const float velToneBoostBase = 1.0f + 0.6f * velCurve;  // up to 60% brighter at ff
        const float pitchToneScale = 1.0f + 0.25f * noteNorm;  // higher notes naturally brighter
        const float trebleToneComp = DebugToggles::kEnablePm2TrebleToneComp
                                         ? (1.0f - 0.45f * juce::jlimit (0.0f, 1.0f, (midiNoteNumber - 72.0f) / 36.0f))
                                         : 1.0f;
        const float velToneBoost = velToneBoostBase * (1.0f - 0.20f * noteNorm);
        
        // Base tone frequency from preset, scaled by velocity and pitch
        const float toneHzScaled = toneHzEff * velToneBoost * pitchToneScale * trebleToneComp;
        const float minToneHz = juce::jmax (toneHzScaled, (float) hz * 3.0f);
        const float toneHzMax = mixLinear (20000.0f, 12000.0f, juce::jlimit (0.0f, 1.0f, (midiNoteNumber - 72.0f) / 36.0f));
        const float toneHz = juce::jlimit (2000.0f, toneHzMax, minToneHz);
        const float theta = 2.0f * juce::MathConstants<float>::pi * toneHz / (float) sampleRate;
        const float alpha = std::exp (-theta);
        float lpState = 0.0f;
        s.feltState = 0.0f;
        s.feltLastOut = 0.0f;
        s.feltEnvPrev = 0.0f;
        float preload = juce::jlimit (0.0f, 1.0f, felt.preload * preloadScale);
        float preloadPow = std::pow (preload, juce::jlimit (1.0f, 5.0f, felt.stiffness));
        float stiffness = juce::jlimit (1.0f, 5.0f, felt.stiffness * stiffnessScale);
        float hyst = juce::jlimit (0.0f, 0.6f, felt.hysteresis);
        float maxAmp = juce::jlimit (0.2f, 4.0f, felt.maxAmp);
        float maxDelta = maxAmp * 0.5f;
        if (! DebugToggles::kEnablePm2FeltShaping)
        {
            preload = 0.0f;
            preloadPow = 0.0f;
            stiffness = 1.0f;
            hyst = 0.0f;
            maxAmp = 10.0f;
            maxDelta = maxAmp * 0.5f;
        }

        // FIX: Smooth autoSimplify transition - use gradual blend instead of hard cutoff at 84
        const float simplifyNorm = juce::jlimit (0.0f, 1.0f, ((float) midiNoteNumber - 80.0f) / 16.0f);
        const bool autoSimplify = (simplifyNorm > 0.5f) || (v < 0.25f) || highPolyMode;
        bool useSimplified = (hammer.simplifiedMode || autoSimplify) && DebugToggles::kEnablePm2SimplifiedBurst;
        if (PhysicsToggles::kUsePhysicsDefaults)
            useSimplified = false;
        // Avoid simplified burst in high notes to reduce squeak/quack.
        if (midiNoteNumber >= 72)
            useSimplified = false;
        // FIX: Previously disabled hammer excitation for notes >= C5 (MIDI 72), which caused
        // high notes to sound thin/squeaky and truncated. The hammer-string interaction is
        // essential for proper piano timbre at all pitches.
        const bool disableExcitation = false;  // Enable hammer for all notes
        std::vector<float> wdfBurst;
        const auto wdfSafe = sanitizeWdf (wdf);
        bool allowWdfBurst = true;
        if (v < 0.6f)
        {
            // Skip 1 out of 4 low-velocity notes to reduce CPU in burst generation.
            static uint32_t wdfSkipCounter = 0;
            allowWdfBurst = ((wdfSkipCounter++ % 4u) != 3u);
        }
        const bool useWdf = DebugToggles::kEnablePm2WdfBurst
                            && DebugToggles::kEnablePm2SimplifiedBurst
                            && ! economyMode && ! highPolyMode
                            && wdfSafe.enabled && wdfSafe.blend > 1.0e-4f && allowWdfBurst
                            && midiNoteNumber < 96;  // Extended from 84 to reduce split audibility
        if (useSimplified && useWdf)
        {
            wdfBurst = buildWdfBurst (sampleRate,
                                      hz,
                                      juce::jlimit (0.0f, 1.0f, v),
                                      totalExcite,
                                      wdfSafe.loss,
                                      wdfSafe.bridgeMass,
                                      wdfSafe.plateStiffness,
                                      rng);
            for (auto& sample : wdfBurst)
            {
                if (! std::isfinite (sample))
                    sample = 0.0f;
                sample = juce::jlimit (-2.0f, 2.0f, sample);
            }
        }
        const float wdfBlend = wdfSafe.blend;
        const float wdfTrebleAtten = DebugToggles::kEnablePm2WdfTrebleAtten
                                         ? (1.0f - 0.50f * juce::jlimit (0.0f, 1.0f, ((float) midiNoteNumber - 72.0f) / 36.0f))
                                         : 1.0f;
        const int wdfRamp = juce::jmax (1, totalExcite / 4);

        if (useSimplified)
        {
            if (! DebugToggles::kEnablePm2HammerExcitation)
            {
                for (auto& sample : s.delay) sample = 0.0f;
            }
            else
            {
            int envAttack = juce::jmin (attackSamples, totalExcite / 3);
            int envDecay = juce::jmin (decaySamples, totalExcite / 2);
            envAttack = juce::jmax (1, (int) std::round (envAttack * 0.5f)); // steeper onset
            envDecay  = juce::jmax (1, (int) std::round (envDecay  * 0.75f));
            const int envRelease = juce::jmax (0, totalExcite - envAttack - envDecay);

            const int delaySize = (int) s.delay.size();
            const int writeCount = juce::jmin (totalExcite, delaySize);
            for (int n = 0; n < totalExcite; ++n)
            {
                float env = 0.0f;
                if (n < envAttack) 
                    env = (float) n / juce::jmax (1.0f, (float) envAttack);
                else if (n < envAttack + envDecay)
                {
                    const float t = (float) (n - envAttack) / juce::jmax (1.0f, (float) envDecay);
                    env = 1.0f - 0.85f * t;
                }
                else if (envRelease > 0)
                {
                    const float t = (float) (n - envAttack - envDecay) / juce::jmax (1.0f, (float) envRelease);
                    env = juce::jmax (0.0f, 0.15f * (1.0f - t));
                }

                // IMPROVEMENT 1: Pink noise for more realistic spectral density
                // Voss-McCartney approximation creates inter-harmonic energy
                float whiteNoise = randomUniform() * 2.0f - 1.0f;
                
                // Update pink noise octave bands at different rates
                pinkNoiseCounter++;
                if ((pinkNoiseCounter & 0x01) == 0) 
                    pinkNoiseState[0] = randomUniform() * 2.0f - 1.0f;
                if ((pinkNoiseCounter & 0x03) == 0) 
                    pinkNoiseState[1] = randomUniform() * 2.0f - 1.0f;
                if ((pinkNoiseCounter & 0x0F) == 0) 
                    pinkNoiseState[2] = randomUniform() * 2.0f - 1.0f;
                float pinkNoise = (pinkNoiseState[0] + pinkNoiseState[1] + pinkNoiseState[2] + whiteNoise) * 0.25f;
                
                // Mix white (brightness/attack) and pink (body/warmth) based on velocity and pitch
                // Lower velocity and lower notes get more pink noise for warmth
                // Higher velocity and higher notes get more white noise for brightness
                const float noteNormMix = juce::jlimit (0.0f, 1.0f, ((float) midiNoteNumber - 21.0f) / 87.0f);
                const float pinkTrebleBoost = 0.12f * noteNormMix;
                const float pinkMix = juce::jlimit (0.25f, 0.75f,
                                                    0.45f - 0.15f * velCurve + 0.08f * (1.0f - noteNormMix)
                                                    + pinkTrebleBoost);
                float noise = (whiteNoise * (1.0f - pinkMix) + pinkNoise * pinkMix) * env * exciteGain;
                
                lpState = lpState + (1.0f - alpha) * (noise - lpState);

                float mag = std::pow (preload + std::abs (lpState), stiffness) - preloadPow;
                float shaped = (1.0f - hyst) * mag + hyst * s.feltState;
                s.feltState = shaped;

                float envDeriv = env - s.feltEnvPrev;
                s.feltEnvPrev = env;
                float rateBoost = juce::jlimit (0.8f, 1.4f, 1.0f + envDeriv * 2.0f);

                float burst = softClip ((float) std::copysign (shaped * rateBoost, lpState), maxAmp);
                float delta = burst - s.feltLastOut;
                delta = softClip (delta, maxDelta);
                burst = s.feltLastOut + delta;
                s.feltLastOut = burst;
                
                // IMPROVEMENT 9: Add subtle attack transient noise
                // Simulates felt compression noise and mechanical "thunk" character
                // Most prominent in first few ms of note, filtered to mid-high frequencies
                // FIX: Smooth fade-out from note 72 to 84 instead of hard cutoff at 76
                const float transientFade = 1.0f - juce::jlimit (0.0f, 1.0f, ((float) midiNoteNumber - 72.0f) / 12.0f);
                if (transientFade > 0.01f && n < envAttack + envDecay / 2)
                {
                    const float transientProgress = (float) n / (float) (envAttack + envDecay / 2);
                    // Quadratic decay envelope for transient
                    const float transientEnv = (1.0f - transientProgress) * (1.0f - transientProgress);
                    
                    // Generate transient noise scaled by velocity (harder hits = more thunk)
                    const float transientTrebleAtten = 1.0f - 0.85f * noteNormMix;
                    float transientNoise = (randomUniform() * 2.0f - 1.0f) * transientEnv * exciteGain * 0.12f * velCurve * transientTrebleAtten;
                    
                    // Simple highpass approximation at ~300Hz for "thunk" character
                    // Using differentiation: hp[n] = x[n] - x[n-1] * (1-coeff)
                    static thread_local float transientHpState = 0.0f;
                    if (n == 0) transientHpState = 0.0f;  // Reset for each string
                    const float hpCoeff = 0.92f;  // ~300Hz highpass
                    float hpOut = transientNoise - transientHpState * hpCoeff;
                    transientHpState = transientNoise;
                    
                    // FIX: Apply smooth fade for higher notes
                    burst += hpOut * transientFade;
                }
                
                if (useWdf && n < (int) wdfBurst.size())
                {
                    const float ramp = juce::jlimit (0.0f, 1.0f, (float) n / (float) wdfRamp);
                    const float blend = juce::jlimit (0.0f, 1.0f, wdfBlend * wdfTrebleAtten * ramp);
                    burst = mixLinear (burst, wdfBurst[(size_t) n], blend);
                }
                if (n < writeCount)
                    s.delay[(size_t) n] = burst;
            }
            if (writeCount < delaySize)
            {
                for (int n = writeCount; n < delaySize; ++n)
                    s.delay[(size_t) n] = 0.0f;
            }
            }
        }
        else
        {
            for (auto& sample : s.delay) sample = 0.0f;
            if (PhysicsToggles::kUsePhysicsDefaults)
            {
                const float periodSamples = (float) juce::jmax (4.0, s.delaySamples);
                const int seedSamples = juce::jlimit (4, (int) s.delay.size(),
                                                      (int) std::round (periodSamples * 2.0f));
                const float seedAmp = 0.08f * exciteGain;  // Reduced from 0.12f to lower levels
                for (int n = 0; n < seedSamples; ++n)
                    s.delay[(size_t) n] = std::sin (juce::MathConstants<float>::twoPi
                                                    * (float) n / periodSamples) * seedAmp;
            }
            if (! DebugToggles::kEnablePm2HammerExcitation || disableExcitation)
                s.hammer.active = false;
            else
                s.hammer.active = true;
            // FIX: Allow hammer interaction to continue beyond the delay line size
            // This gives longer, more natural hammer-string contact especially for higher notes
            // The interaction now runs for the full attack window + tail, not limited by delay line
            const float pedalLift = juce::jlimit (0.0f, 1.0f, sustainPedalDown ? 1.0f : damperLiftTarget);
            const float pedalTailScale = 1.0f + 0.6f * pedalLift;
            const int hammerTailSamples = juce::jmax (1, (int) std::round (decaySamples * 4 * pedalTailScale));  // Longer tail when pedal is down
            const int minHammerSamples = (int) std::round ((0.20f + 0.06f * pedalLift) * sampleRate);  // 200-260ms interaction
            s.hammer.samplesLeft = juce::jmax (minHammerSamples, hammerWindowSamples + hammerTailSamples);
            s.hammer.samplesTotal = s.hammer.samplesLeft;
            s.hammer.samplesElapsed = 0;
            s.hammer.pos = 0.0f;
            const float strikeBoost = juce::jlimit (0.90f, 1.05f, 0.95f + 0.15f * v);  // softer onset to reduce spike
            s.hammer.vel = exciteGain * 1.2f * strikeBoost;  // Reduced from 1.6f to lower levels
            s.hammer.pen = 0.0f;
            float hammerMass = hammer.massKg;
            float hammerK = hammer.contactStiffness;
            float hammerExp = hammer.contactExponent;
            float hammerDamping = hammer.contactDamping;
            if (PhysicsToggles::kUsePerNotePhysics)
            {
                hammerMass = PianoPhysics::Hammer::getMass (midiNoteNumber);
                hammerK = mapHammerStiffnessToModel (PianoPhysics::Hammer::getStiffness (midiNoteNumber));
                hammerExp = PianoPhysics::Hammer::getExponent (midiNoteNumber);
                const float physHyst = PianoPhysics::Hammer::getHysteresis (midiNoteNumber);
                hammerDamping = juce::jmap (physHyst, 0.08f, 0.18f, 4.0f, 8.0f);
            }

            s.hammer.mass = juce::jlimit (0.005f, 0.08f, hammerMass);
            s.hammer.k = juce::jlimit (200.0f, 20000.0f, hammerK * stiffnessScale);
            s.hammer.exp = juce::jlimit (1.4f, 4.0f, hammerExp);
            s.hammer.damping = juce::jlimit (0.5f, 40.0f, hammerDamping);
            s.hammer.preload = juce::jlimit (0.0f, 1.0f, hammer.force * 0.5f + preload * 0.5f);
            s.hammer.preload = juce::jlimit (0.0f, 1.0f, s.hammer.preload * preloadScale);
            s.hammer.maxPen = juce::jlimit (0.0005f, 0.030f, hammer.maxPenetration);
            s.hammer.toneAlpha = juce::jlimit (0.0f, 0.9999f, alpha);
        s.hammer.toneState = 0.0f;
            // FIX: Increased hammer gain significantly for stronger excitation
            // This ensures the initial transient has enough energy to sustain
            s.hammer.gain = 0.008f * juce::jlimit (0.9f, 1.25f, 0.9f + 0.35f * v);  // Reduced from 0.012 to lower levels
            s.hammer.gainSmoothed = DebugToggles::kEnablePm2HammerGainRamp ? 0.0f : s.hammer.gain;
            s.hammer.simplified = false;
        }

        const bool enableDuplex = (! economyMode) || currentMidiNote <= 100;
        const float duplexGainDb = juce::jlimit (-20.0f, -6.0f, duplex.gainDb);
        const float duplexGainLin = juce::Decibels::decibelsToGain (duplexGainDb);
        // CPU optimisation: Only apply duplex to the first (loudest) string
        // This preserves most of the afterlength effect while reducing cost by ~67% for 3-string setups
        const bool useDuplex = DebugToggles::kEnablePm2Duplex
                               && ! economyMode && ! highPolyMode && enableDuplex
                               && (duplexGainDb > -19.5f) && (i == 0) && ! lowVelSkip;
        if (useDuplex)
        {
            // duplex buffer length ~ afterlength
            float ratio = juce::jlimit (1.1f, 4.0f, duplex.ratio);
            double duplexDelay = delaySamples / ratio;
            const int dlen = juce::jmax (4, (int) std::ceil (duplexDelay));
            s.duplex.buf.resize ((size_t) dlen);
            std::fill (s.duplex.buf.begin(), s.duplex.buf.end(), 0.0f);
            s.duplex.write = 0;
            s.duplex.gain = juce::jlimit (0.0f, 0.5f, duplexGainLin);
            // decayMs -> feedback factor
            double decayMs = juce::jlimit (10.0, 400.0, (double) duplex.decayMs);
            double tauSamples = (decayMs * 0.001) * sampleRate;
            double fb = std::exp (-1.0 / juce::jmax (8.0, tauSamples));
            s.duplex.feedback = (float) juce::jlimit (0.0, 0.99, fb);
            s.duplex.inputGain = 0.15f;
        }
        else
        {
            s.duplex.buf.clear();
            s.duplex.write = 0;
            s.duplex.gain = 0.0f;
            s.duplex.feedback = 0.0f;
            s.duplex.inputGain = 0.0f;
        }

        s.baseGain = params.gain[(size_t) i];
        // CPU OPTIMIZATION: Apply bass third string fade for notes below G2
        // This gradually reduces the third string's contribution in the bass register
        if (i == 2)
            s.baseGain *= thirdStringGainScale;
        const float pan = juce::jlimit (-1.0f, 1.0f, params.pan[(size_t) i] * stereoWidth);
        s.panGainL = std::sqrt (0.5f * (1.0f - pan));
        s.panGainR = std::sqrt (0.5f * (1.0f + pan));
        
        // IMPROVEMENT 2: Initialize fundamental boost lowpass
        // Uses lowpass extraction on the output to boost fundamental region
        // Only the first string's state is used (for the summed output)
        if (i == 0)
        {
            // Lowpass cutoff at ~1.5x fundamental to capture fundamental region
            const float lpCutoffHz = juce::jlimit (40.0f, 800.0f, (float) hz * 1.5f);
            
            // One-pole lowpass coefficient: alpha = exp(-2*pi*fc/fs)
            const float lpAlpha = std::exp (-2.0f * juce::MathConstants<float>::pi * lpCutoffHz / (float) sampleRate);
            s.fundResonatorCoeff = lpAlpha;
            
            // Pitch-dependent gain: boost more in mid-range where fundamental weakness is most noticeable
            // Reduce boost for extreme bass (already fundamental-heavy) and extreme treble (short strings)
            const float fundBoostNorm = 1.0f - std::abs ((float) midiNoteNumber - 60.0f) / 48.0f;
            const float fundBoostClamped = juce::jmax (0.0f, fundBoostNorm);
            s.fundResonatorGain = juce::jlimit (0.02f, 0.15f, 0.10f * fundBoostClamped);
            
            // Reset filter state
            s.fundResonatorState1 = 0.0f;
            s.fundResonatorState2 = 0.0f;
        }
        else
        {
            // Other strings don't use these (only string 0's state is used for output boost)
            s.fundResonatorCoeff = 0.0f;
            s.fundResonatorGain = 0.0f;
            s.fundResonatorState1 = 0.0f;
            s.fundResonatorState2 = 0.0f;
        }
    }

    // Option 5: Initialize anti-swell envelope - slow decay for high notes only
    // Decay rate: 0 for notes below E4(64), increasing to ~0.5dB/sec at C8(108)
    antiSwellEnv = 1.0f;
        if (DebugToggles::kEnablePm2AntiSwell)
        {
            const float antiSwellNoteNorm = DebugToggles::kEnablePm2AntiSwellTreblePivot
                                                ? juce::jlimit (0.0f, 1.0f, ((float) midiNoteNumber - 72.0f) / 48.0f)
                                                : 0.0f;
            // Convert dB/sec to linear decay per sample: lighter damping for high notes
            const float dbPerSecMax = 0.15f;
        const float dbPerSec = dbPerSecMax * antiSwellNoteNorm * antiSwellNoteNorm;  // Quadratic curve
        const float dbPerSample = dbPerSec / (float) sampleRate;
        antiSwellDecayPerSample = std::pow (10.0f, -dbPerSample / 20.0f);  // Convert to linear multiplier
    }
    else
    {
        antiSwellDecayPerSample = 1.0f;
    }

    adsr.noteOn();
    active = true;
}

void Pm2StringBank::hardRetrigger (int midiNoteNumber, float velocity)
{
    resetForHardRetrigger();
    noteOn (midiNoteNumber, velocity);
}

void Pm2StringBank::noteOff()
{
    if (minNoteOffRemaining > 0)
    {
        pendingNoteOff = true;
        return;
    }
    applyNoteOffInternal();
}

void Pm2StringBank::applyNoteOffInternal()
{
    keyHeld = false;
    if (sustainPedalDown && ! stealInProgress)
        return; // wait for pedal release to start tail decay

    const float releaseMs = PhysicsToggles::kUsePhysicsDefaults ? 0.002f : 0.002f;  // 2ms release
    keyReleaseSamplesTotal = juce::jmax (1, (int) std::round (releaseMs * sampleRate));
    keyReleaseSamplesRemaining = keyReleaseSamplesTotal;
    const float fadeMs = 0.001f;  // 1ms fade
    keyOffFadeSamplesTotal = juce::jmax (1, (int) std::round (fadeMs * sampleRate));
    keyOffFadeSamplesRemaining = keyOffFadeSamplesTotal;
    useReleaseLoopGain = true;
    releaseDelaySamples = 0;
    damperDelaySamples = PhysicsToggles::kUsePhysicsDefaults ? (int) std::round (0.001f * sampleRate) : 0;  // 1ms damper delay - nearly instant
    adsr.noteOff();
    postLpfEnv.noteOff();
}

void Pm2StringBank::forceSilence()
{
    adsr.reset();
    postLpfEnv.reset();
    active = false;
    currentMidiNote = -1;
    pedalChangeSamplesRemaining = 0;
    pedalChangeFade = 1.0f;
    minNoteOffRemaining = 0;
    pendingNoteOff = false;
    for (auto& s : strings)
    {
        std::fill (s.delay.begin(), s.delay.end(), 0.0f);
        s.lpState = 0.0f;
        s.damperSoftenState = 0.0f;
        s.damperLossSmoothed = damper.lossOff;
        s.dc = {};
    }
    lastEnv = 0.0f;
    lastOutL = 0.0f;
    lastOutR = 0.0f;
    postLpfStateL = 0.0f;
    postLpfStateR = 0.0f;
    loopEnergySmoothed = 0.0f;
    // FIX #3: Only reset steal fade if we're NOT in a steal operation.
    // When voice stealing, we want the fade to complete to avoid clicks.
    if (! stealInProgress)
        stealFadeRemaining = 0;
    stealInProgress = false;  // Clear the flag after use
}

void Pm2StringBank::resetForHardRetrigger()
{
    adsr.reset();
    postLpfEnv.reset();
    active = false;
    keyHeld = false;
    useReleaseLoopGain = false;
    keyReleaseSamplesRemaining = 0;
    keyOffFadeSamplesRemaining = 0;
    noteFadeSamplesRemaining = 0;
    noteFadeSamplesTotal = 0;
    lowVelSkip = false;
    minNoteOffRemaining = 0;
    pendingNoteOff = false;
    stealFadeRemaining = 0;
    stealFadeSamples = 0;
    stealInProgress = false;
    pedalChangeSamplesRemaining = 0;
    pedalChangeFade = 1.0f;
    antiSwellEnv = 1.0f;
    antiSwellDecayPerSample = 1.0f;
    loopEnergySmoothed = 0.0f;
    lastEnv = 0.0f;
    lastOutL = 0.0f;
    lastOutR = 0.0f;
    postLpfStateL = 0.0f;
    postLpfStateR = 0.0f;
    for (auto& s : strings)
    {
        std::fill (s.delay.begin(), s.delay.end(), 0.0f);
        s.writePos = 0;
        s.lpState = 0.0f;
        s.damperSoftenState = 0.0f;
        s.damperLossSmoothed = damper.lossOff;
        s.damperLossPrev = damper.lossOff;
        s.interpZ1 = 0.0f;
        s.hammer = {};
        s.duplex.buf.clear();
        s.duplex.write = 0;
        s.duplex.feedback = 0.0f;
        s.duplex.gain = 0.0f;
        s.duplex.inputGain = 0.0f;
        if (sampleRate > 0.0)
            s.dc.reset (sampleRate);
        else
            s.dc = {};
        s.energyCalibSamplesLeft = 0;
        s.energyCalibComplete = false;
        s.energyPeak = 0.0f;
        s.energySmoothed = 0.0f;
        s.energyGainSmoothed = 1.0f;
    }
}

float Pm2StringBank::randomUniform()
{
    rng = 1664525u * rng + 1013904223u;
    return (rng >> 8) * (1.0f / 16777216.0f);
}

void Pm2StringBank::render (juce::AudioBuffer<float>& buffer, int startSample, int numSamples, int startSampleInBlock)
{
    if (! active && ! adsr.isActive())
        return;

    const float dt = (float) (1.0 / juce::jmax (20.0, sampleRate));
    auto* L = buffer.getWritePointer (0, startSample);
    auto* R = buffer.getNumChannels() > 1 ? buffer.getWritePointer (1, startSample) : nullptr;
    float blockAbsMax = 0.0f;
    const bool undampedSend = keyHeld || sustainPedalDown;
    const bool damperEnabled = DebugToggles::kEnablePm2Damper;
    const bool couplingEnabled = DebugToggles::kEnableCoupling;
    const bool stringFiltersEnabled = DebugToggles::kEnablePm2StringFilters;
    
    const float couplingGainEff = (economyMode || ! couplingEnabled) ? 0.0f : couplingGain * polyphonyScale;
    const float sympGainEff = (economyMode || ! couplingEnabled) ? 0.0f : sympGain * polyphonyScale;
    const bool skipBodyNoise = economyMode;
    const bool skipDuplex = false;
    const float softGainScale = softPedalDown ? juce::jlimit (0.0f, 1.0f, unaCorda.gainScale) : 1.0f;

    for (int i = 0; i < numSamples; ++i)
    {
        if (minNoteOffRemaining > 0)
        {
            --minNoteOffRemaining;
            if (minNoteOffRemaining == 0 && pendingNoteOff)
            {
                pendingNoteOff = false;
                applyNoteOffInternal();
            }
        }
        if (pedalChangeSamplesRemaining > 0 && pedalChangeSamplesTotal > 0)
        {
            float t = 1.0f - (float) pedalChangeSamplesRemaining / (float) pedalChangeSamplesTotal;
            t = juce::jlimit (0.0f, 1.0f, t);
            pedalChangeFade = t * t * (3.0f - 2.0f * t);
            --pedalChangeSamplesRemaining;
        }
        else
        {
            pedalChangeFade = 1.0f;
        }

        float stealGain = 1.0f;
        if (stealFadeRemaining > 0 && stealFadeSamples > 0)
        {
            stealGain = (float) stealFadeRemaining / (float) stealFadeSamples;
            --stealFadeRemaining;
        }

        float sumL = 0.0f, sumR = 0.0f;
        float loopEnergySample = 0.0f;
        for (int sIdx = 0; sIdx < currentNumStrings; ++sIdx)
        {
            auto& s = strings[(size_t) sIdx];
            if (s.delay.empty()) continue;

            const int len = (int) s.delay.size();
            
            float y = 0.0f;
            // Use cheaper linear interpolation for economy mode and treble notes
            if (economyMode || ! DebugToggles::kEnablePm2FracDelayInterp || currentMidiNote >= 84)
            {
                // Cheaper linear interpolation
                double readPos = (double) s.writePos - s.delaySamples;
                while (readPos < 0.0) readPos += (double) len;
                while (readPos >= (double) len) readPos -= (double) len;
                int i1 = (int) std::floor (readPos);
                float frac = (float) (readPos - (double) i1);
                int i0 = i1;
                int i2 = (i1 + 1) % len;
                float x1 = s.delay[(size_t) i0];
                float x2 = s.delay[(size_t) i2];
                y = x1 + frac * (x2 - x1);
            }
            else
            {
                // Thiran first-order allpass interpolation for fractional delay
                // Much cheaper than Lagrange (1 read + state vs 4 reads + 15 FMAs)
                // while maintaining flat magnitude response (ideal for physical modelling)
                // 
                // Formula (transposed direct form II):
                //   y = alpha * x + z1
                //   z1_new = x - alpha * y
                // where alpha = (1-d)/(1+d), d = fractional delay
                
                // Read from integer delay position
                const int intDelay = (int) std::floor (s.delaySamples);
                int readIdx = s.writePos - intDelay;
                while (readIdx < 0) readIdx += len;
                const float x = s.delay[(size_t) readIdx];
                
                // Apply allpass for fractional delay
                const float alpha = s.interpAlpha;
                y = alpha * x + s.interpZ1;
                s.interpZ1 = x - alpha * y;
            }

            // dispersion allpass chain
            for (int k = 0; k < s.apStages; ++k)
                y = s.ap[(size_t) k].process (y);

        // loop loss (scalar) + frequency-dependent loss via one-pole LP
        float damperLossTarget = 1.0f;
            if (damperEnabled)
            {
                // Smooth damper lift changes to avoid zipper noise under rapid pedal motion.
                damperLiftSmoothed += damperLiftSmoothCoeff * (damperLiftTarget - damperLiftSmoothed);
                // Treat the damper as fully lifted while the key (or sustain pedal) is down.
                // When the key is released, ramp the damper transition over a few ms to avoid clicks.
                float releaseBlend = 0.0f;
                if (keyHeld || sustainPedalDown)
                {
                    releaseBlend = 1.0f;
                }
                else if (PhysicsToggles::kUsePhysicsDefaults && damperDelaySamples > 0)
                {
                    --damperDelaySamples;
                    releaseBlend = 1.0f;
                }
                else if (keyReleaseSamplesRemaining > 0 && keyReleaseSamplesTotal > 0)
                {
                    releaseBlend = (float) keyReleaseSamplesRemaining / (float) keyReleaseSamplesTotal;
                    --keyReleaseSamplesRemaining;
                }
                const float damperLiftEffective = damperLiftSmoothed + (1.0f - damperLiftSmoothed) * releaseBlend;

                damperLossTarget = (damperLiftEffective >= 0.999f)
                                   ? damper.lossOff
                                   : mixLinear (damper.lossDamped, damper.lossHalf, damperLiftEffective);
                const float damperCoeff = DebugToggles::kEnablePm2ExtraDamperSmoothing
                                              ? (damperSmoothCoeff * 0.5f)
                                              : damperSmoothCoeff;
                s.damperLossSmoothed += damperCoeff * (damperLossTarget - s.damperLossSmoothed);
            }
            else
            {
                damperLiftSmoothed = 1.0f;
                s.damperLossSmoothed = 1.0f;
                s.damperLossPrev = 1.0f;
            }
            if (releaseDelaySamples > 0)
                --releaseDelaySamples;
            if (releaseDelaySamples == 0 && ! useReleaseLoopGain && ! keyHeld && ! sustainPedalDown)
                useReleaseLoopGain = true;
            float loopTarget = (useReleaseLoopGain ? s.loopGainRelease : s.loopGainBase)
                               * (damperEnabled ? s.damperLossSmoothed : 1.0f);
            if (DebugToggles::kEnablePm2FreqDependentLoss)
                loopTarget *= freqLossScalar;
            const float swellScale = PhysicsToggles::kUsePhysicsDefaults ? 0.6f : 1.0f;
            if (DebugToggles::kEnablePm2HighNoteLoopDamping)
            {
                if (sustainPedalDown)
                {
                    // Gentle swell prevention for high notes with pedal down
                    const float noteNorm = juce::jlimit (0.0f, 1.0f, ((float) currentMidiNote - 68.0f) / 36.0f);//1st value is midi note it starts at 2nd value is notespan of big reduction
                    const float sustainSwellDamp = 1.0f - (0.0008f * swellScale) * noteNorm;
                    loopTarget *= sustainSwellDamp;
                }
                else
                {
                    // Extra high-note damping without sustain to prevent runaway
                    const float noteNorm = juce::jlimit (0.0f, 1.0f, ((float) currentMidiNote - 84.0f) / 40.0f); // ~C6 to C9
                    const float noPedalHighDamp = 1.0f - (0.0020f * swellScale) * noteNorm;
                    loopTarget *= noPedalHighDamp;
                }
            }
            const float loopCoeff = DebugToggles::kEnablePm2ExtraLoopGainSmoothing
                                        ? (damperSmoothCoeff * 0.5f)
                                        : damperSmoothCoeff;
            s.loopGainSmoothed += loopCoeff * (loopTarget - s.loopGainSmoothed);
            if (damperEnabled)
            {
                if (damperLossTarget < s.damperLossPrev - 1.0e-4f)
                    s.damperSoftenCountdown = damperSoftenSamples;
                s.damperLossPrev = damperLossTarget;
            }

            y *= s.loopGainSmoothed;
            if (stringFiltersEnabled)
            {
                float lp = s.lpState + s.lpCoeff * (y - s.lpState);
                s.lpState = lp;
                y = lp;
            }
            loopEnergySample += y * y;

            // Option 1: Per-string energy limiter to prevent swell
            // During calibration window, capture peak energy level
            // After calibration, soft-limit to prevent exceeding ~110% of reference
            if (! economyMode && DebugToggles::kEnablePm2EnergyLimiter && ! PhysicsToggles::kUsePhysicsDefaults)
            {
                const float absY = std::abs (y);
                // Smooth energy tracking (fast attack, slow release)
                const float noteNormHigh = juce::jlimit (0.0f, 1.0f, ((float) currentMidiNote - 76.0f) / 32.0f); // E5 to G7
                const float energyAttack = mixLinear (0.095f, 0.13f, noteNormHigh);   // Faster attack for treble
                const float energyRelease = 0.001f; // Slow release
                const float energyCoeff = (absY > s.energySmoothed) ? energyAttack : energyRelease;
                s.energySmoothed += energyCoeff * (absY - s.energySmoothed);
                
                if (! s.energyCalibComplete)
                {
                    // During calibration: track peak energy
                    if (s.energySmoothed > s.energyPeak)
                        s.energyPeak = s.energySmoothed;
                    --s.energyCalibSamplesLeft;
                    if (s.energyCalibSamplesLeft <= 0)
                    {
                        s.energyCalibComplete = true;
                        // Add 10% headroom to avoid limiting normal dynamics
                        const float headroom = mixLinear (1.35f, 1.25f, noteNormHigh);
                        s.energyPeak *= headroom;
                        // Minimum floor to avoid division issues on very quiet notes
                        s.energyPeak = juce::jmax (s.energyPeak, 0.003f);
                    }
                }
                else if (s.energyPeak > 0.0f)
                {
                    // After calibration: soft-limit if energy exceeds reference
                    const float ratio = s.energySmoothed / s.energyPeak;
                    float targetGain = 1.0f;
                    if (ratio > 1.0f)
                    {
                        // Soft knee limiter: gentle compression above threshold
                        const float excess = ratio - 1.0f;
                        const float compRatio = mixLinear (1.15f, 1.45f, noteNormHigh);
                        targetGain = 1.0f / (1.0f + excess * compRatio);
                    }
                    targetGain = juce::jmax (0.6f, targetGain);
                    const float gainAttack = mixLinear (0.10f, 0.14f, noteNormHigh);
                    const float gainRelease = 0.006f;
                    const float gainCoeff = (targetGain < s.energyGainSmoothed) ? gainAttack : gainRelease;
                    s.energyGainSmoothed += gainCoeff * (targetGain - s.energyGainSmoothed);
                    y *= s.energyGainSmoothed;
                }
            }

            if (damperEnabled && s.damperSoftenCountdown > 0)
            {
                const float softenMix = 1.0f - damperSoftenA;
                s.damperSoftenState = s.damperSoftenState + softenMix * (y - s.damperSoftenState);
                y = s.damperSoftenState;
                --s.damperSoftenCountdown;
            }

            // dc block
            if (DebugToggles::kEnablePm2DcBlock)
                y = s.dc.process (y);

            // Continuous hammer-string interaction (adds excitation during attack)
            float excitation = 0.0f;
            if (DebugToggles::kEnablePm2HammerExcitation && s.hammer.active && s.hammer.samplesLeft > 0)
            {
                auto& h = s.hammer;
                float pen = h.pos - y;
                pen = juce::jlimit (-h.maxPen, h.maxPen, pen);
                float contact = juce::jmax (0.0f, pen + h.preload);
                // CPU OPTIMIZATION: Use fastPow for hammer force calculation
                float force = h.k * FastMath::fastPow (contact, h.exp) - h.damping * h.vel;
                force = softClip (force, 1200.0f);  // softer clamp to avoid discontinuities
                float accel = force / juce::jmax (0.001f, h.mass);
                h.vel += accel * dt;
                h.pos += h.vel * dt;
                h.pen = pen;
                float shaped = h.toneState + (1.0f - h.toneAlpha) * (force - h.toneState);
                h.toneState = shaped;
                // FIX: Scale excitation based on remaining interaction time for smoother decay
                // This prevents the abrupt cutoff when samplesLeft reaches 0
                const float fadeStart = 200.0f;  // Start fading in last 200 samples
                float fadeGain = (h.samplesLeft > fadeStart) ? 1.0f
                               : (float) h.samplesLeft / fadeStart;
                // Slight fade-in to soften the initial spike
                const float fadeInSamples = 120.0f;
                const float fadeInGain = (h.samplesElapsed < fadeInSamples)
                                       ? (float) h.samplesElapsed / fadeInSamples
                                       : 1.0f;
                float hammerGain = h.gain;
                if (DebugToggles::kEnablePm2HammerGainRamp)
                {
                    const float gainCoeff = 0.02f;
                    h.gainSmoothed += gainCoeff * (hammerGain - h.gainSmoothed);
                    hammerGain = h.gainSmoothed;
                }
            excitation = softClip (shaped * hammerGain * fadeGain * fadeInGain, 3.0f);
            if (PhysicsToggles::kUsePhysicsDefaults && s.toneInjectSamplesLeft > 0)
            {
                excitation += FastMath::fastSin (s.toneInjectPhase) * s.toneInjectGain;
                s.toneInjectPhase += s.toneInjectPhaseDelta;
                if (s.toneInjectPhase >= juce::MathConstants<float>::twoPi)
                    s.toneInjectPhase -= juce::MathConstants<float>::twoPi;
                --s.toneInjectSamplesLeft;
            }
                --h.samplesLeft;
                ++h.samplesElapsed;
                if (! std::isfinite (h.pos) || ! std::isfinite (h.vel) || h.samplesLeft <= 0 || (h.pos <= 0.0f && h.vel <= 0.0f))
                    h.active = false;
            }

            // write back
            float writeSample = softClip (y + excitation, 4.0f);
            s.delay[(size_t) s.writePos] = writeSample;
            s.writePos = (s.writePos + 1) % len;

            float mono = y * s.baseGain * softGainScale;
            if (PhysicsToggles::kUsePhysicsDefaults && s.toneInjectSamplesLeft > 0)
            {
                mono += FastMath::fastSin (s.toneInjectPhase) * s.toneInjectGain;
                s.toneInjectPhase += s.toneInjectPhaseDelta;
                if (s.toneInjectPhase >= juce::MathConstants<float>::twoPi)
                    s.toneInjectPhase -= juce::MathConstants<float>::twoPi;
                --s.toneInjectSamplesLeft;
            }
            sumL += mono * s.panGainL;
            sumR += mono * s.panGainR;

            // duplex tap (short afterlength)
            // CPU OPTIMIZATION: Skip for bass notes (less audible in low register)
            if (! skipDuplex && ! s.duplex.buf.empty())
            {
                float prev = s.duplex.buf[(size_t) s.duplex.write];
                float input = y * s.duplex.inputGain;
                s.duplex.buf[(size_t) s.duplex.write] = input + s.duplex.feedback * prev;
                s.duplex.write = (s.duplex.write + 1) % (int) s.duplex.buf.size();
                float duplexMono = prev * s.duplex.gain;
                sumL += duplexMono * s.panGainL;
                sumR += duplexMono * s.panGainR;
            }
        }

        // IMPROVEMENT 3: Add stochastic body resonance (inter-harmonic fill)
        // Simulates soundboard and cabinet broadband resonance that fills gaps between harmonics
        // Modulated by loop energy so it follows the note's amplitude envelope
        // CPU OPTIMIZATION: Skip for bass notes (less audible in low register)
        if (! skipBodyNoise)
        {
            const float loopEnergy = FastMath::fastSqrt (juce::jmax (0.0f, loopEnergySmoothed));
            const float noiseLevel = loopEnergy * 0.003f;  // Reduced from 0.006f to lower noise floor
            const bool allowBodyNoise = adsr.isActive() && loopEnergySmoothed > 1.0e-4f;
            
            if (allowBodyNoise && noiseLevel > 1.0e-6f)
            {
                // Generate filtered noise (bandpass ~80-2500 Hz range)
                bodyNoiseRng = 1664525u * bodyNoiseRng + 1013904223u;
                float rawNoise = ((bodyNoiseRng >> 8) * (1.0f / 16777216.0f)) * 2.0f - 1.0f;
                
                // Two-pole lowpass - reduced cutoff for less HF content
                const float lpCoeff = 0.08f;  // Was 0.12f - lower cutoff ~2kHz
                bodyNoiseLp1 += lpCoeff * (rawNoise - bodyNoiseLp1);
                bodyNoiseLp2 += lpCoeff * (bodyNoiseLp1 - bodyNoiseLp2);
                
                // One-pole highpass at ~80Hz to remove rumble
                const float hpCoeff = 0.995f;
                float filtered = bodyNoiseLp2 - bodyNoiseHp;
                bodyNoiseHp = bodyNoiseLp2 * (1.0f - hpCoeff) + bodyNoiseHp * hpCoeff;
                
                // Apply energy modulation
                float bodyNoise = filtered * noiseLevel;
                
                // Slight stereo decorrelation for natural width
                bodyNoiseRng = 1664525u * bodyNoiseRng + 1013904223u;
                float stereoOffset = ((bodyNoiseRng >> 16) * (1.0f / 65536.0f)) * 0.3f;
                
                sumL += bodyNoise * (0.5f + stereoOffset);
                sumR += bodyNoise * (0.5f - stereoOffset);
            }
        }

        // IMPROVEMENT 2: Output-stage fundamental boost using lowpass extraction
        // Extract low frequencies (fundamental region) and mix back for warmer tone
        // This is applied to the output sum, NOT inside the waveguide loop
        {
            // Use the first string's resonator state for the summed output
            // Simple one-pole lowpass to extract fundamental region (~200Hz cutoff)
            auto& s = strings[0];
            const float lpAlpha = s.fundResonatorCoeff;  // Pre-calculated in noteOn based on fundamental
            if (s.fundResonatorGain > 0.001f && lpAlpha > 0.0f)
            {
                // Extract low frequency content
                s.fundResonatorState1 += (1.0f - lpAlpha) * (sumL - s.fundResonatorState1);
                s.fundResonatorState2 += (1.0f - lpAlpha) * (sumR - s.fundResonatorState2);
                
                // Mix extracted lows back in for fundamental boost
                sumL += s.fundResonatorState1 * s.fundResonatorGain;
                sumR += s.fundResonatorState2 * s.fundResonatorGain;
            }
        }

        loopEnergySmoothed += loopEnergySmoothCoeff * (loopEnergySample - loopEnergySmoothed);
        lastEnv = loopEnergySmoothed;
        // FIXED: Apply stringGainNorm to prevent level buildup from multi-string summing
        float outL = sumL * pitchLoudnessGain * stringGainNorm;
        float outR = sumR * pitchLoudnessGain * stringGainNorm;
        if (! std::isfinite (outL)) outL = lastOutL * 0.98f;
        if (! std::isfinite (outR)) outR = lastOutR * 0.98f;
        const bool noteHpfEnabled = DebugToggles::kEnablePm2NoteHpf;
        float hpL = noteHpfEnabled ? noteHpf.processSample (0, outL) : outL;
        float hpR = noteHpfEnabled ? noteHpf.processSample (noteHpfNumChannels > 1 ? 1 : 0, outR) : outR;
        if (DebugToggles::kEnablePm2PostLpfEnv)
        {
            const float env = postLpfEnv.getNextSample();
            const float cutoff = juce::jlimit (400.0f, 16000.0f,
                                               postLpfMinHz + (postLpfMaxHz - postLpfMinHz) * env);
            const float a = std::exp (-2.0f * juce::MathConstants<float>::pi * cutoff
                                      / (float) juce::jmax (20.0, sampleRate));
            postLpfStateL = a * postLpfStateL + (1.0f - a) * hpL;
            postLpfStateR = a * postLpfStateR + (1.0f - a) * hpR;
            hpL = postLpfStateL;
            hpR = postLpfStateR;
        }
        // FIX #1 & #4: Use instance bus pointers with block-relative indices
        // Weak coupling/sympathetic returns from other notes
        const int busIdx = startSampleInBlock + i;  // Block-relative index for shared buses
        const auto coupleIn = (couplingEnabled && couplingBus) ? couplingBus->read (busIdx) : std::make_pair (0.0f, 0.0f);
        const auto sympIn   = (couplingEnabled && sympBus) ? sympBus->read (busIdx) : std::make_pair (0.0f, 0.0f);
        
        // Option 2: Reduce coupling and sympathetic return for high notes to prevent swell
        // High notes are more prone to energy accumulation from these feedback paths
        const float highNoteNorm = DebugToggles::kEnablePm2HighNoteCouplingTilt
                                       ? juce::jlimit (0.0f, 1.0f, ((float) currentMidiNote - 72.0f) / 48.0f)
                                       : 0.0f;
        const float coupleTilt = 1.0f - 0.6f * highNoteNorm * highNoteNorm;  // Quadratic reduction, lighter and spread wider
        const float sympTilt = 1.0f - sympHighDamp * highNoteNorm - 0.25f * highNoteNorm * highNoteNorm;  // Extra quadratic term
        
            const float pedalFade = pedalChangeFade;
            const float coupleGain = couplingGainEff * pedalFade;
            const float sympGainScaled = sympGainEff * pedalFade;
            float coupleL = (coupleGain > 1.0e-4f) ? couplingBpL.processSample (0, coupleIn.first) * coupleGain * coupleTilt : 0.0f;
            float coupleR = (coupleGain > 1.0e-4f) ? couplingBpR.processSample (noteHpfNumChannels > 1 ? 1 : 0, coupleIn.second) * coupleGain * coupleTilt : 0.0f;
            float sympL = (sympGainScaled > 1.0e-4f) ? sympBpL.processSample (0, sympIn.first) * (sympGainScaled * sympTilt) : 0.0f;
            float sympR = (sympGainScaled > 1.0e-4f) ? sympBpR.processSample (noteHpfNumChannels > 1 ? 1 : 0, sympIn.second) * (sympGainScaled * sympTilt) : 0.0f;
        hpL += coupleL + sympL;
        hpR += coupleR + sympR;
        hpL *= stealGain * velocityGain;
        hpR *= stealGain * velocityGain;
        if (noteFadeSamplesRemaining > 0 && noteFadeSamplesTotal > 0)
        {
            const float fadeT = 1.0f - (float) noteFadeSamplesRemaining / (float) noteFadeSamplesTotal;
            hpL *= fadeT;
            hpR *= fadeT;
            --noteFadeSamplesRemaining;
        }
        if (! keyHeld && ! sustainPedalDown && keyOffFadeSamplesRemaining > 0 && keyOffFadeSamplesTotal > 0)
        {
            const float fadeT = 1.0f - (float) keyOffFadeSamplesRemaining / (float) keyOffFadeSamplesTotal;
            hpL *= fadeT;
            hpR *= fadeT;
            --keyOffFadeSamplesRemaining;
        }
        
        // Option 5: Apply anti-swell envelope - very slow decay for high notes
        // This counteracts gradual energy accumulation that causes swell
        if (DebugToggles::kEnablePm2AntiSwell)
        {
            hpL *= antiSwellEnv;
            hpR *= antiSwellEnv;
            // Decay the envelope (only when key is held to prevent affecting release)
            if (keyHeld || sustainPedalDown)
                antiSwellEnv *= antiSwellDecayPerSample;
            // Floor to prevent envelope from going to zero over very long holds
            antiSwellEnv = juce::jmax (antiSwellEnv, 0.9f);
        }
        
        if (R)
        {
            L[i] += hpL;
            R[i] += hpR;
        }
        else
        {
            L[i] += 0.5f * (hpL + hpR);
        }
        lastOutL = hpL;
        lastOutR = hpR;
        blockAbsMax = std::max (blockAbsMax, std::max (std::abs (hpL), std::abs (hpR)));
        // FIX #1 & #4: Use instance bus pointers with block-relative indices
        if (couplingEnabled && couplingBus && couplingGainEff > 1.0e-4f)
            couplingBus->add (busIdx, hpL * pedalChangeFade, hpR * pedalChangeFade);
        if (couplingEnabled && undampedSend && sympBus && ! lowVelSkip && sympGainEff > 1.0e-4f)
            sympBus->add (busIdx, hpL * pedalChangeFade, hpR * pedalChangeFade);

        if (stealFadeSamples > 0 && stealFadeRemaining == 0)
        {
            forceSilence();
            return;
        }
    }

    noteLifeSamples += numSamples;
    // CPU OPTIMIZATION: Very aggressive thresholds for faster voice termination
    // Notes that have decayed below audibility are terminated quickly to free CPU
    // These thresholds are 4-5x more aggressive than previous values
    const float energyThresholdBase = PhysicsToggles::kUsePhysicsDefaults ? 5.0e-4f : 8.0e-4f;
    const float blockThresholdBase = PhysicsToggles::kUsePhysicsDefaults ? 2.0e-4f : 3.0e-4f;
    const int minLifeBase = PhysicsToggles::kUsePhysicsDefaults ? (int) std::round (0.003 * sampleRate) : 0;  // 3ms minimum
    const float stopNoteNorm = juce::jlimit (0.0f, 1.0f, ((float) currentMidiNote - 72.0f) / 36.0f);
    const float stopScale = 1.0f - 0.85f * stopNoteNorm;  // More aggressive scaling for high notes
    const float energyThreshold = energyThresholdBase * juce::jmax (0.2f, stopScale);
    const float blockThreshold = blockThresholdBase * juce::jmax (0.2f, stopScale);
    const int minLife = minLifeBase + (int) std::round (stopNoteNorm * 0.010 * sampleRate);  // 10ms extra for high notes
    if (! keyHeld && ! sustainPedalDown
        && loopEnergySmoothed < energyThreshold && blockAbsMax < blockThreshold
        && noteLifeSamples > minLife)
    {
        adsr.reset();
        active = false;
    }
}

void Pm2Synth::preallocateVoiceForNote (int midiNoteNumber)
{
    juce::ignoreUnused (midiNoteNumber);

    int active = 0;
    for (int i = 0; i < getNumVoices(); ++i)
        if (auto* v = getVoice (i))
            if (v->isVoiceActive())
                ++active;

    if (active < getNumVoices())
        return; // at least one free voice, no need to steal

    // Voice stealing: pick the quietest voice by loop energy
    juce::SynthesiserVoice* best = nullptr;
    float bestEnergy = std::numeric_limits<float>::max();

    for (int i = 0; i < getNumVoices(); ++i)
    {
        auto* v = getVoice (i);
        if (v == nullptr)
            continue;

        if (auto* pv = dynamic_cast<Pm2Voice*> (v))
        {
            float energy = pv->getLoopEnergy();
            if (! std::isfinite (energy))
                energy = std::numeric_limits<float>::max();
            if (energy < bestEnergy)
            {
                bestEnergy = energy;
                best = v;
            }
        }
    }

    if (auto* pv = dynamic_cast<Pm2Voice*> (best))
    {
        pv->prepareForSteal();
        pv->stopNote (0.0f, true); // allow tail-off for smoother steal
        requestDeclick (64);
    }
}

// FIX: Preallocate multiple voices for a chord - ensures all notes in a chord get voices
// without JUCE's internal voice stealing interfering with our age-based priority
void Pm2Synth::preallocateVoicesForChord (int numNotesNeeded)
{
    if (numNotesNeeded <= 0)
        return;

    // Count currently active voices
    int activeCount = 0;
    for (int i = 0; i < getNumVoices(); ++i)
        if (auto* v = getVoice (i))
            if (v->isVoiceActive())
                ++activeCount;

    // Calculate how many voices we need to free
    const int totalVoices = getNumVoices();
    const int freeVoices = totalVoices - activeCount;
    int voicesToSteal = numNotesNeeded - freeVoices;

    // Steal voices one at a time, always picking the oldest
    while (voicesToSteal > 0)
    {
        // Find the quietest note to steal by loop energy
        juce::SynthesiserVoice* best = nullptr;
        float bestEnergy = std::numeric_limits<float>::max();

        for (int i = 0; i < getNumVoices(); ++i)
        {
            auto* v = getVoice (i);
            if (v == nullptr || ! v->isVoiceActive())
                continue;

            if (auto* pv = dynamic_cast<Pm2Voice*> (v))
            {
                float energy = pv->getLoopEnergy();
                if (! std::isfinite (energy))
                    energy = std::numeric_limits<float>::max();
                if (energy < bestEnergy)
                {
                    bestEnergy = energy;
                    best = v;
                }
            }
        }

        if (auto* pv = dynamic_cast<Pm2Voice*> (best))
        {
            pv->prepareForSteal();
            pv->stopNote (0.0f, true); // allow tail-off for smoother steal
            requestDeclick (64);
            --voicesToSteal;
        }
        else
        {
            // No more voices to steal, break to avoid infinite loop
            break;
        }
    }
}

bool Pm2Synth::hasActiveVoiceForNote (int midiNoteNumber) const
{
    for (int i = 0; i < getNumVoices(); ++i)
        if (auto* v = dynamic_cast<Pm2Voice*> (getVoice (i)))
            if (v->isActive() && v->getCurrentMidiNote() == midiNoteNumber)
                return true;
    return false;
}

bool Pm2Synth::hardRetriggerActiveVoice (int midiNoteNumber, float velocity)
{
    Pm2Voice* best = nullptr;
    uint64_t bestAge = 0;
    for (int i = 0; i < getNumVoices(); ++i)
        if (auto* v = dynamic_cast<Pm2Voice*> (getVoice (i)))
            if (v->isActive() && v->getCurrentMidiNote() == midiNoteNumber)
            {
                const uint64_t age = v->getNoteAge();
                if (best == nullptr || age > bestAge)
                {
                    best = v;
                    bestAge = age;
                }
            }
    if (best == nullptr)
        return false;
    best->hardRetrigger (midiNoteNumber, velocity);
    return true;
}

//==============================================================================
// Processor ctor
FluteSynthAudioProcessor::FluteSynthAudioProcessor()
#ifndef JucePlugin_PreferredChannelConfigurations
    : AudioProcessor (BusesProperties().withOutput ("Output", juce::AudioChannelSet::stereo(), true))
#endif
    , apvts (*this, nullptr, "Params", createParameterLayout())
{
    // CPU OPTIMIZATION: Reduced polyphony from 18 to 15 voices
    for (int i = 0; i < 15; ++i)
        synth.addVoice (new FluteVoice (apvts));
    synth.addSound (new SimpleSound());

    for (int i = 0; i < 15; ++i)
        pmSynth.addVoice (new PmVoice());
    pmSynth.addSound (new PmSound());

    for (int i = 0; i < 15; ++i)
        pm2Synth.addVoice (new Pm2Voice());
    pm2Synth.addSound (new Pm2Sound());
    
    // FIX #1: Set shared bus pointers on all PM2 voices
    pm2Synth.setSharedBuses (&couplingBus, &sympBus);

    applyMasterTuneToVoices();
    loadEmbeddedPreset();
}

void FluteSynthAudioProcessor::prepareToPlay (double sr, int samplesPerBlock)
{
    // CPU OPTIMIZATION: Initialize fast math lookup tables (only done once)
    FastMath::initTables();
    
    lastSampleRate = sr;
    prepared = true;
    applyMasterTuneToVoices();
    {
        const double smoothTimeSec = 0.020; // ~20ms smoothing for click reduction
        auto resetSmooth = [sr, smoothTimeSec] (juce::SmoothedValue<float, juce::ValueSmoothingTypes::Linear>& s, float value)
        {
            s.reset (sr, smoothTimeSec);
            s.setCurrentAndTargetValue (value);
        };
        resetSmooth (pm2GainLinSmoothed, pm2GainLin);
        resetSmooth (outputGainLinSmoothed, outputGainLin);
        resetSmooth (postCutoffHzSmoothed, postCutoffHz);
        resetSmooth (postQSmoothed, postQ);
        resetSmooth (postTiltDbSmoothed, postTiltDb);
        resetSmooth (outputLpfCutoffSmoothed, outputLpfCutoff);
        resetSmooth (outputLpfQSmoothed, outputLpfQ);
        resetSmooth (sustainGainLinSmoothed, 1.0f);
        resetSmooth (sustainReleaseScaleSmoothed, 1.0f);
        resetSmooth (sustainValueSmoothed, 0.0f);
        const float noteTerm = brightnessNoteSlopeDb * ((float) lastMidiNote - 60.0f) * (1.0f / 24.0f);
        const float initialBrightness = juce::jlimit (-12.0f, brightnessMaxDb,
                                                      brightnessBaseDb + lastVelocityNorm * brightnessVelSlopeDb + noteTerm);
        resetSmooth (brightnessDbSmoothed, initialBrightness);
        brightnessCurrentDb = initialBrightness;
    }

    // VA synth
    synth.setCurrentPlaybackSampleRate (sr);
    for (int i = 0; i < synth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<FluteVoice*> (synth.getVoice (i)))
        {
            v->prepare (sr, samplesPerBlock, getTotalNumOutputChannels());
            v->setNoteOffsets (noteOffsetsCents);
        }

    pmSynth.setCurrentPlaybackSampleRate (sr);
    for (int i = 0; i < pmSynth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<PmVoice*> (pmSynth.getVoice (i)))
        {
            v->prepare (sr, samplesPerBlock, getTotalNumOutputChannels());
            v->setNoteOffsets (noteOffsetsCents);
        }

    pm2Synth.setCurrentPlaybackSampleRate (sr);
    for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
        {
            v->prepare (sr, samplesPerBlock, getTotalNumOutputChannels());
            v->setNoteOffsets (noteOffsetsCents);
        }

    // Sync PM/PM2 voice params to current state on prepare
    const float a = apvts.getRawParameterValue (ParamIDs::attack)->load();
    const float d = apvts.getRawParameterValue (ParamIDs::decay)->load();
    const float s = apvts.getRawParameterValue (ParamIDs::sustain)->load();
    const float r = apvts.getRawParameterValue (ParamIDs::release)->load();
    baseRelease = r;
    for (int i = 0; i < pmSynth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<PmVoice*> (pmSynth.getVoice (i)))
        {
            v->setEnvParams (a, d, s, r);
            v->setReleaseScale (baseRelease, 1.0f);
        }
    for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
        {
            v->setEnvParams (a, d, s, r);
            v->setParams (pmString);
            v->setHammerParams (pmHammer);
            v->setFeltParams (pmFelt);
            v->setDuplexParams (duplexCfg);
            v->setWdfParams (wdfCfg);
            v->setSoftPedal (softPedalDown, unaCfg);
            v->setReleaseScale (baseRelease, 1.0f);
            v->setReleaseExtension (releaseExtension);
            v->setSustainPedalDown (sustainPedalDown);
            v->setDamperParams (damperCfg);
            v->setDamperLift (damperLift);
            v->setEconomyMode (pm2EconomyMode);
            v->setHighPolyMode (pm2EconomyMode);
            v->setCouplingParams (couplingCfg);
            v->setDispersionCurve (dispersionCfg);
        }
    
    // FIX #1: Ensure shared bus pointers are set on all PM2 voices
    pm2Synth.setSharedBuses (&couplingBus, &sympBus);

    // Breath + formants
    juce::dsp::ProcessSpec spec;
    spec.sampleRate = sr;
    spec.maximumBlockSize = (juce::uint32) samplesPerBlock;
    spec.numChannels = (juce::uint32) juce::jmax (1, getTotalNumOutputChannels());
    mainSpec = spec;

    auto allocScratch = [] (juce::AudioBuffer<float>& buf, int channels, int samples)
    {
        buf.setSize (channels, samples, false, false, true);
        buf.clear();
    };
    const int scratchCh = (int) spec.numChannels;
    allocScratch (hybridVaBuf, scratchCh, samplesPerBlock);
    allocScratch (hybridPmBuf, scratchCh, samplesPerBlock);
    allocScratch (hybridPm2Buf, scratchCh, samplesPerBlock);
    allocScratch (micScratch, scratchCh, samplesPerBlock);
    allocScratch (breathScratch, 1, samplesPerBlock);
    allocScratch (formantScratch, scratchCh, samplesPerBlock);
    allocScratch (pedalScratch, scratchCh, samplesPerBlock);
    allocScratch (sympScratch, scratchCh, samplesPerBlock);
    allocScratch (modalScratch, scratchCh, samplesPerBlock);
    allocScratch (soundboardScratch, scratchCh, samplesPerBlock);
    if (DebugToggles::kSoundboardConvolutionDownsample > 1)
    {
        const int dsSamples = (samplesPerBlock + DebugToggles::kSoundboardConvolutionDownsample - 1)
                                / DebugToggles::kSoundboardConvolutionDownsample;
        allocScratch (soundboardScratchDs, scratchCh, dsSamples);
    }
    soundboardConvolution.reset();
    soundboardConvolution.prepare (spec);
    if (DebugToggles::kSoundboardConvolutionDownsample > 1)
    {
        juce::dsp::ProcessSpec dsSpec = spec;
        dsSpec.sampleRate = spec.sampleRate / (double) DebugToggles::kSoundboardConvolutionDownsample;
        dsSpec.maximumBlockSize = (juce::uint32)
            ((spec.maximumBlockSize + DebugToggles::kSoundboardConvolutionDownsample - 1)
             / DebugToggles::kSoundboardConvolutionDownsample);
        soundboardConvolutionDs.reset();
        soundboardConvolutionDs.prepare (dsSpec);
    }
    soundboardIrDirty = true;
    soundboardIrLastT60 = 0.0f;
    soundboardIrLastDamp = 0.0f;
    postReverb.reset();
    postReverbParamsValid = false;

    breathBp.reset();   breathBp.prepare (spec);
    breathBp.setType (juce::dsp::StateVariableTPTFilterType::bandpass);
    breathBp.setCutoffFrequency (breathBpFreqStored);
    breathBp.setResonance       (breathBpQStored);

    for (int i = 0; i < 2; ++i)
    {
        formant[i].f.reset();
        formant[i].f.prepare (spec);
        formant[i].f.setType (juce::dsp::StateVariableTPTFilterType::bandpass);
        formant[i].gainLin = 1.0f;
        formant[i].enabled = false;
    }

    // Post tone controls (per-engine key-tracked LPF cascaded + shared tilt shelves)
    auto prepLP = [&spec] (juce::dsp::StateVariableTPTFilter<float>& f)
    {
        f.reset();
        f.prepare (spec);
        f.setType (juce::dsp::StateVariableTPTFilterType::lowpass);
    };
    prepLP (postVaLp1);  prepLP (postVaLp2);
    prepLP (postPmLp1);  prepLP (postPmLp2);
    prepLP (postPm2Lp1); prepLP (postPm2Lp2);

    tiltLow.reset(); tiltHigh.reset();
    tiltLow.prepare (spec); tiltHigh.prepare (spec);
    tiltNumChannels = (int) spec.numChannels;
    tiltReady = false;

    auto prepSendHpf = [this] (decltype (pedalSendHpf)& f)
    {
        f.reset();
        f.prepare (mainSpec);
        auto coeffs = juce::dsp::IIR::Coefficients<float>::makeHighPass (mainSpec.sampleRate,
                                                                         sendHpfCutoff,
                                                                         0.707f);
        if (f.state == nullptr)
            f.state = coeffs;
        else
            *f.state = *coeffs;
    };
    prepSendHpf (pedalSendHpf);
    prepSendHpf (sympSendHpf);
    prepSendHpf (soundboardSendHpf);
    {
        soundboardReturnHpf.reset();
        soundboardReturnHpf.prepare (mainSpec);
        auto coeffs = juce::dsp::IIR::Coefficients<float>::makeHighPass (mainSpec.sampleRate,
                                                                         soundboardReturnHpfCutoff,
                                                                         0.707f);
        if (soundboardReturnHpf.state == nullptr)
            soundboardReturnHpf.state = coeffs;
        else
            *soundboardReturnHpf.state = *coeffs;
    }
    {
        juce::dsp::ProcessSpec monoSpec = mainSpec;
        monoSpec.numChannels = 1;
        modalSendHpf.reset();
        modalSendHpf.prepare (monoSpec);
        modalSendHpf.coefficients = juce::dsp::IIR::Coefficients<float>::makeHighPass (monoSpec.sampleRate,
                                                                                       sendHpfCutoff,
                                                                                       0.707f);
    }
    sendHpfNumChannels = (int) mainSpec.numChannels;

    // Final output LPF
    outputLpf.reset();
    outputLpf.prepare (spec);
    outputLpf.setType (juce::dsp::StateVariableTPTFilterType::lowpass);
    outputLpfNumChannels = (int) spec.numChannels;
    updateOutputLpf();
    for (auto& f : outputEqFilters)
    {
        f.reset();
        f.prepare (spec);
    }
    outputEqNumChannels = (int) spec.numChannels;
    updateOutputEq();
    // Output HPF for rumble control
    outputHpf.reset();
    outputHpf.prepare (spec);
    {
        auto coeffs = juce::dsp::IIR::Coefficients<float>::makeHighPass (spec.sampleRate,
                                                                         outputHpfCutoff,
                                                                         0.707f);
        if (outputHpf.state == nullptr)
            outputHpf.state = coeffs;
        else
            *outputHpf.state = *coeffs;
    }
    outputHpfNumChannels = (int) spec.numChannels;

    // Lookahead final limiter
    {
        const int la = juce::jmax (1, (int) std::round (sr * (limiterLookaheadMs * 0.001f)));
        limiterLookaheadSamples = la;
        limiterDelayBufferSize = la + samplesPerBlock + 1;
        limiterDelayBuffer.setSize ((int) spec.numChannels, limiterDelayBufferSize, false, false, true);
        limiterDelayBuffer.clear();
        limiterWritePos = 0;
        limiterGain = 1.0f;
        auto msToCoeff = [sr] (float ms)
        {
            const double sec = juce::jmax (0.0001, (double) ms * 0.001);
            return (float) std::exp (-1.0 / (sec * sr));
        };
        limiterAttackCoeff = msToCoeff (limiterAttackMs);
        limiterReleaseCoeff = msToCoeff (limiterReleaseMs);
        setLatencySamples (limiterLookaheadSamples);
    }

    prepareBrightnessFilters();
    for (int ch = 0; ch < juce::jmin (2, (int) spec.numChannels); ++ch)
        outputDcBlock[(size_t) ch].reset (sr);
    outputDcNumChannels = (int) spec.numChannels;

    // Mic mixer setup
    updateMicProcessors();

    // Hammer HP
    hammerHP.reset();
    hammerHP.prepare (juce::dsp::ProcessSpec{ sr, (juce::uint32) samplesPerBlock, 1u });
    hammerHP.setType (juce::dsp::StateVariableTPTFilterType::highpass);
    hammerHP.setCutoffFrequency (hammerHpHz);
    // Recalculate hammer decay coefficient now that sample rate is valid
    // (may have been skipped during construction when lastSampleRate was 0)
    if (hammerDecaySec > 0.0005f)
    {
        const double tau = std::max (0.0005, (double) hammerDecaySec);
        hammerDecayCoeff = (float) std::exp (-1.0 / (tau * sr));
    }
    else
    {
        hammerDecayCoeff = 0.0f;
    }

    // Action noises
    auto decayToCoeff = [sr] (float sec)
    {
        if (sec <= 0.0005f) return 0.0f;
        const double tau = std::max (0.0005, (double) sec);
        return (float) std::exp (-1.0 / (tau * sr));
    };

    keyOffHP.reset();
    keyOffHP.prepare (juce::dsp::ProcessSpec{ sr, (juce::uint32) samplesPerBlock, 1u });
    keyOffHP.setType (juce::dsp::StateVariableTPTFilterType::highpass);
    keyOffHP.setCutoffFrequency (keyOffHpHz);
    keyOffDecayCoeff = decayToCoeff (keyOffDecaySec);

    pedalThumpLP.reset();
    pedalThumpLP.prepare (juce::dsp::ProcessSpec{ sr, (juce::uint32) samplesPerBlock, 1u });
    pedalThumpLP.setType (juce::dsp::StateVariableTPTFilterType::lowpass);
    pedalThumpLP.setCutoffFrequency (pedalThumpLpHz);
    pedalThumpDecayCoeff = decayToCoeff (pedalThumpDecaySec);

    releaseThumpLP.reset();
    releaseThumpLP.prepare (juce::dsp::ProcessSpec{ sr, (juce::uint32) samplesPerBlock, 1u });
    releaseThumpLP.setType (juce::dsp::StateVariableTPTFilterType::lowpass);
    releaseThumpLP.setCutoffFrequency (releaseThumpLpHz);
    releaseThudHP.reset();
    releaseThudHP.prepare (juce::dsp::ProcessSpec{ sr, (juce::uint32) samplesPerBlock, 1u });
    releaseThudHP.setType (juce::dsp::StateVariableTPTFilterType::highpass);
    releaseThudHP.setCutoffFrequency (releaseThudHpHz);
    releaseThumpDecayCoeff = decayToCoeff (releaseThumpDecaySec);

    updateDamperCoeffs();

    // Soundboard
    soundboardReverb.reset();
    soundboardConvolution.reset();
    soundboardConvolutionDs.reset();
    pedalReverb.reset();
    pedalReverbParamsValid = false;
    sympParamsValid = false;
    soundboardParamsValid = false;
    postReverb.reset();
    postReverbParamsValid = false;
    modalChannels = juce::jmax (1, juce::jmin (2, getTotalNumOutputChannels()));
    const int maxPredelaySamples = (int) std::ceil (sr * 0.020); // pmPredelayMs clamps to 20 ms
    predelayCapacitySamples = juce::jmax (256, maxPredelaySamples + samplesPerBlock + 2);
    predelayBuf.assign ((size_t) predelayCapacitySamples, 0.0f);
    predelayWrite = 0;
    modalDirty = true;

    // Apply current APVTS values to runtime state after DSP is prepared.
    syncExtendedParamsFromAPVTS();
    updateSoundboardConvolution (true);

    updatePostFiltersForNote (lastMidiNote);
}

void FluteSynthAudioProcessor::releaseResources() { prepared = false; tiltReady = false; }

juce::AudioProcessorEditor* FluteSynthAudioProcessor::createEditor()
{
    return new FluteSynthAudioProcessorEditor (*this);
}

#ifndef JucePlugin_PreferredChannelConfigurations
bool FluteSynthAudioProcessor::isBusesLayoutSupported (const BusesLayout& layouts) const
{
    auto out = layouts.getMainOutputChannelSet();
    return out == juce::AudioChannelSet::mono() || out == juce::AudioChannelSet::stereo();
}
#endif

static inline float fastRand01(uint32_t& s)
{
    s = 1664525u * s + 1013904223u;
    return (float)((s >> 8) * (1.0 / 16777216.0)); // ~[0..1)
}

static juce::dsp::IIR::Coefficients<float>::Ptr makeBandPass (double sr, float f, float q)
{
    f = juce::jlimit (60.0f, 5000.0f, f);
    q = juce::jlimit (0.7f, 8.0f, q);
    return juce::dsp::IIR::Coefficients<float>::makeBandPass (sr, f, q);
}

void FluteSynthAudioProcessor::updateSoundboardConvolution (bool force)
{
    if (! DebugToggles::kEnableSoundboardConvolution)
        return;
    if (! prepared || lastSampleRate <= 0.0)
        return;
    if (! force && ! soundboardIrDirty)
        return;

    auto ir = buildSoundboardIr (lastSampleRate, soundboardT60Sec, soundboardDampParam);
    const size_t irSamples = (size_t) ir.getNumSamples();
    if (irSamples > 0)
    {
#if JUCE_VERSION_MAJOR >= 7
        soundboardConvolution.loadImpulseResponse (std::move (ir),
                                                   lastSampleRate,
                                                   juce::dsp::Convolution::Stereo::no,
                                                   juce::dsp::Convolution::Trim::no,
                                                   juce::dsp::Convolution::Normalise::no);
#else
        soundboardConvolution.loadImpulseResponse (std::move (ir),
                                                   lastSampleRate,
                                                   juce::dsp::Convolution::Stereo::no,
                                                   juce::dsp::Convolution::Trim::no,
                                                   juce::dsp::Convolution::Normalise::no);
#endif
    }
    if (DebugToggles::kSoundboardConvolutionDownsample > 1)
    {
        const double dsRate = lastSampleRate / (double) DebugToggles::kSoundboardConvolutionDownsample;
        auto irDs = buildSoundboardIr (dsRate, soundboardT60Sec, soundboardDampParam);
        if (irDs.getNumSamples() > 0)
        {
#if JUCE_VERSION_MAJOR >= 7
            soundboardConvolutionDs.loadImpulseResponse (std::move (irDs),
                                                         dsRate,
                                                         juce::dsp::Convolution::Stereo::no,
                                                         juce::dsp::Convolution::Trim::no,
                                                         juce::dsp::Convolution::Normalise::no);
#else
            soundboardConvolutionDs.loadImpulseResponse (std::move (irDs),
                                                         dsRate,
                                                         juce::dsp::Convolution::Stereo::no,
                                                         juce::dsp::Convolution::Trim::no,
                                                         juce::dsp::Convolution::Normalise::no);
#endif
        }
    }
    soundboardIrLastT60 = soundboardT60Sec;
    soundboardIrLastDamp = soundboardDampParam;
    soundboardIrDirty = false;
}

juce::AudioBuffer<float> FluteSynthAudioProcessor::buildSoundboardIr (double sampleRate, float t60Sec, float damp) const
{
    t60Sec = juce::jlimit (0.9f, 2.4f, t60Sec);
    damp = juce::jlimit (0.0f, 1.0f, damp);

    const float lengthSec = juce::jlimit (0.50f, 1.60f, 0.50f + 0.45f * t60Sec);
    const int numSamples = juce::jmax (64, (int) std::round (lengthSec * sampleRate));
    juce::AudioBuffer<float> ir (1, numSamples);
    ir.clear();

    struct Mode
    {
        float phase { 0.0f };
        float phaseInc { 0.0f };
        float amp { 0.0f };
        float decay { 0.999f };
    };

    const int numModes = 48;
    const float fMin = 190.0f;
    const float fMax = 2200.0f;
    const float twoPi = juce::MathConstants<float>::twoPi;
    uint32_t seed = 0x1F2E3D4Cu;

    std::vector<Mode> modes;
    modes.reserve ((size_t) numModes);

    for (int i = 0; i < numModes; ++i)
    {
        float r = (float) (i + 1) / (float) (numModes + 1);
        r = r * r * r; // cluster modes toward low-mid for more tonal body
        r += (fastRand01 (seed) - 0.5f) * 0.025f;
        r = juce::jlimit (0.0f, 1.0f, r);
        const float freq = fMin * std::pow (fMax / fMin, r);
        const float freqNorm = freq / fMax;
        float modeT60 = t60Sec / (1.0f + damp * (0.9f + 3.5f * freqNorm));
        modeT60 = juce::jlimit (0.10f, t60Sec, modeT60);
        const double tau = modeT60 / std::log (1000.0);
        const float decay = (float) std::exp (-1.0 / (tau * sampleRate));
        const float amp = 0.08f * std::pow (1.0f - r, 1.2f) / std::sqrt (freq / fMin);
        const float phase = fastRand01 (seed) * twoPi;
        const float phaseInc = twoPi * freq / (float) sampleRate;
        modes.push_back ({ phase, phaseInc, amp, decay });
    }

    float noiseEnv = 1.0f;
    const float noiseTau = 0.003f + 0.004f * (1.0f - damp);
    const float noiseDecay = (float) std::exp (-1.0 / (noiseTau * sampleRate));
    const float noiseAmp = 0.0015f;
    const float lpCutoff = juce::jlimit (900.0f, 2400.0f, 2400.0f - damp * 1200.0f);
    const float lpA = std::exp (-2.0f * juce::MathConstants<float>::pi * lpCutoff / (float) sampleRate);
    float lpState = 0.0f;

    float* out = ir.getWritePointer (0);
    for (int n = 0; n < numSamples; ++n)
    {
        float sum = 0.0f;
        for (auto& m : modes)
        {
            sum += m.amp * std::sin (m.phase);
            m.phase += m.phaseInc;
            if (m.phase > twoPi)
                m.phase -= twoPi;
            m.amp *= m.decay;
        }
        const float noise = (fastRand01 (seed) * 2.0f - 1.0f) * noiseAmp * noiseEnv;
        noiseEnv *= noiseDecay;
        const float raw = sum + noise;
        lpState = (1.0f - lpA) * raw + lpA * lpState;
        out[n] = lpState;
    }

    // Gentle tail fade to avoid abrupt truncation.
    const int fadeSamples = juce::jmax (8, (int) std::round (numSamples * 0.12f));
    for (int i = 0; i < fadeSamples; ++i)
    {
        const float t = (float) i / (float) (fadeSamples - 1);
        const float g = 1.0f - t;
        out[numSamples - fadeSamples + i] *= g;
    }

    float maxAbs = 0.0f;
    for (int i = 0; i < numSamples; ++i)
        maxAbs = juce::jmax (maxAbs, std::abs (out[i]));
    if (maxAbs > 0.0f)
        ir.applyGain (0, numSamples, 0.65f / maxAbs);

    return ir;
}

void FluteSynthAudioProcessor::applyMasterTuneToVoices()
{
    masterTuneFactor = std::pow (2.0f, masterTuneCents * (1.0f / 1200.0f));

    for (int i = 0; i < synth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<FluteVoice*> (synth.getVoice (i)))
            v->setMasterTuneFactor (masterTuneFactor);

    for (int i = 0; i < pmSynth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<PmVoice*> (pmSynth.getVoice (i)))
            v->setMasterTune (masterTuneFactor);

    for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
            v->setMasterTune (masterTuneFactor);
}

bool FluteSynthAudioProcessor::anyVoiceActive() const
{
    for (int i = 0; i < synth.getNumVoices(); ++i)
        if (auto* v = synth.getVoice (i))
            if (v->isVoiceActive())
                return true;
    for (int i = 0; i < pmSynth.getNumVoices(); ++i)
        if (auto* v = pmSynth.getVoice (i))
            if (v->isVoiceActive())
                return true;
    for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
            if (v->isActive())
                return true;
    return false;
}

void FluteSynthAudioProcessor::syncExtendedParamsFromAPVTS()
{
    auto get = [this] (const char* id) { return apvts.getRawParameterValue (id)->load(); };
    auto getB = [this] (const char* id) { return apvts.getRawParameterValue (id)->load() >= 0.5f; };

    // Formants
    auto setFormant = [this, get, getB] (int idx,
                                         const char* enId,
                                         const char* fId,
                                         const char* qId,
                                         const char* gId)
    {
        const bool enabled = getB (enId);
        const float freq   = PresetModel::clamp (get (fId), 300.0f, 12000.0f);
        const float q      = PresetModel::clamp (get (qId),  0.5f,   6.0f);
        const float gDb    = PresetModel::clamp (get (gId), -9.0f,   9.0f);

        formant[idx].enabled = enabled;
        formant[idx].f.setCutoffFrequency (freq);
        formant[idx].f.setResonance (q);
        formant[idx].gainLin = juce::Decibels::decibelsToGain (gDb);
    };

    setFormant (0, ParamIDs::formant1Enable, ParamIDs::formant1Freq, ParamIDs::formant1Q, ParamIDs::formant1GainDb);
    setFormant (1, ParamIDs::formant2Enable, ParamIDs::formant2Freq, ParamIDs::formant2Q, ParamIDs::formant2GainDb);

    // Amp envelope (sync to voices so GUI changes are audible)
    const float a = get (ParamIDs::attack);
    const float d = get (ParamIDs::decay);
    const float s = get (ParamIDs::sustain);
    const float r = get (ParamIDs::release);
    baseRelease = r;
    const float releaseExtScale = juce::jlimit (0.7f, 2.0f,
                                                juce::jmap (r, 0.03f, 7.0f, 0.7f, 2.0f));
    const float releaseExt = releaseExtension * releaseExtScale;
    for (int i = 0; i < pmSynth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<PmVoice*> (pmSynth.getVoice (i)))
            v->setEnvParams (a, d, s, r);
    for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
        {
            v->setEnvParams (a, d, s, r);
            v->setReleaseExtension (releaseExt);
        }

    const int velocityChoice = (int) std::round (get (ParamIDs::velocityCurve));
    float velocityScale = 1.0f;
    velocityFixed = (velocityChoice == 3);
    if (velocityChoice == 0)
        velocityScale = 0.90f;
    else if (velocityChoice == 2)
        velocityScale = 1.15f;
    velocityGamma = juce::jlimit (0.1f, 3.0f, velocityGammaBase * velocityScale);

    // Soundboard
    soundboardEnabled = getB (ParamIDs::soundboardEnable);
    soundboardMix     = juce::jlimit (0.0f, 1.0f, get (ParamIDs::soundboardMix));
    soundboardT60Sec  = juce::jlimit (1.2f, 2.2f, get (ParamIDs::soundboardT60));
    soundboardDampParam = juce::jlimit (0.0f, 1.0f, get (ParamIDs::soundboardDamp));
    if (std::abs (soundboardIrLastT60 - soundboardT60Sec) > 1.0e-4f
        || std::abs (soundboardIrLastDamp - soundboardDampParam) > 1.0e-4f)
        soundboardIrDirty = true;
    soundboardParams.roomSize = juce::jlimit (0.0f, 1.0f, soundboardT60Sec / 3.0f);
    soundboardParams.damping  = soundboardDampParam;
    soundboardParams.width    = 0.6f;
    soundboardParams.wetLevel = 1.0f;
    soundboardParams.dryLevel = 0.0f;
    postRoomMix = juce::jlimit (0.0f, 1.0f, get (ParamIDs::postRoomMix));
    postRoomEnabled = getB (ParamIDs::postRoomEnable);

    // Felt / duplex (pm2)
    pmFelt.preload    = juce::jlimit (0.0f, 0.6f, get (ParamIDs::feltPreload));
    pmFelt.stiffness  = juce::jlimit (1.0f, 5.0f, get (ParamIDs::feltStiffness));
    pmFelt.hysteresis = juce::jlimit (0.0f, 0.6f, get (ParamIDs::feltHysteresis));
    pmFelt.maxAmp     = juce::jlimit (0.4f, 4.0f, get (ParamIDs::feltMax));

    duplexCfg.ratio    = juce::jlimit (1.1f, 4.0f, get (ParamIDs::duplexRatio));
    duplexCfg.gainDb   = juce::jlimit (-20.0f, -6.0f, get (ParamIDs::duplexGainDb));
    duplexCfg.decayMs  = juce::jlimit (10.0f, 400.0f, get (ParamIDs::duplexDecayMs));
    duplexCfg.sympSend = juce::jlimit (0.0f, 1.0f, get (ParamIDs::duplexSympSend));
    duplexCfg.sympMix  = juce::jlimit (0.0f, 1.0f, get (ParamIDs::duplexSympMix));

    pm2GainDb  = juce::jlimit (-24.0f, 42.0f, get (ParamIDs::pm2GainDb));
    pm2GainLin = juce::Decibels::decibelsToGain (pm2GainDb);
    pm2GainLinSmoothed.setTargetValue (pm2GainLin);

    sympParams.roomSize = juce::jlimit (0.0f, 1.0f, duplexCfg.decayMs / 400.0f);
    sympParams.damping  = 0.4f;
    sympParams.wetLevel = 1.0f;
    sympParams.dryLevel = 0.0f;

    for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
        {
            v->setFeltParams (pmFelt);
            v->setDuplexParams (duplexCfg);
        }

    const int temperamentChoice = (int) std::round (get (ParamIDs::temperament));
    if (temperamentChoice == 0)
        noteOffsetsCents = presetNoteOffsetsCents;
    else
        noteOffsetsCents = expandPitchClassOffsets (getTemperamentOffsetsByChoice (temperamentChoice));

    for (int i = 0; i < synth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<FluteVoice*> (synth.getVoice (i)))
            v->setNoteOffsets (noteOffsetsCents);
    for (int i = 0; i < pmSynth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<PmVoice*> (pmSynth.getVoice (i)))
            v->setNoteOffsets (noteOffsetsCents);
    for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
            v->setNoteOffsets (noteOffsetsCents);

    outputLpfEnabled = getB (ParamIDs::outputLpfEnable);
    outputLpfCutoff  = get (ParamIDs::outputLpfCutoff);
    outputLpfQ       = get (ParamIDs::outputLpfQ);
    outputLpfCutoffSmoothed.setTargetValue (outputLpfCutoff);
    outputLpfQSmoothed.setTargetValue (outputLpfQ);
    updateOutputLpf();
}
void FluteSynthAudioProcessor::updatePostFiltersForNote (int midiNote)
{
    if (midiNote > 0)
        lastMidiNote = midiNote;

    updatePostFiltersSmoothed();
}

void FluteSynthAudioProcessor::updatePostFiltersSmoothed()
{
    if (lastSampleRate <= 0.0)
        return;

    const float note = (float) juce::jlimit (0, 127, lastMidiNote);
    const float kt   = juce::jlimit (0.0f, 1.0f, postKeytrack);
    const float baseCutoff = postCutoffHzSmoothed.getCurrentValue();
    const float baseQ = postQSmoothed.getCurrentValue();
    float cutoff     = baseCutoff * std::pow (2.0f, (note - 60.0f) * kt * (1.0f / 12.0f));
    cutoff = juce::jlimit (300.0f, 12000.0f, cutoff);

    auto setLP = [cutoff, q = baseQ] (juce::dsp::StateVariableTPTFilter<float>& f1,
                                      juce::dsp::StateVariableTPTFilter<float>& f2)
    {
        f1.setCutoffFrequency (cutoff);
        f2.setCutoffFrequency (cutoff);
        f1.setResonance (q);
        f2.setResonance (q);
    };
    setLP (postVaLp1, postVaLp2);
    setLP (postPmLp1, postPmLp2);
    setLP (postPm2Lp1, postPm2Lp2);

    const float tilt = juce::jlimit (-6.0f, 6.0f, postTiltDbSmoothed.getCurrentValue());
    const float pivot = 1000.0f;
    const float gHigh = juce::Decibels::decibelsToGain (tilt);
    const float gLow  = juce::Decibels::decibelsToGain (-tilt);
    tiltLow.coefficients  = juce::dsp::IIR::Coefficients<float>::makeLowShelf  (lastSampleRate, pivot, 0.7071f, gLow);
    tiltHigh.coefficients = juce::dsp::IIR::Coefficients<float>::makeHighShelf (lastSampleRate, pivot, 0.7071f, gHigh);
    tiltReady = (tiltLow.coefficients != nullptr && tiltHigh.coefficients != nullptr);
}

void FluteSynthAudioProcessor::updateOutputLpf()
{
    const float cutoff = juce::jlimit (200.0f, 20000.0f, outputLpfCutoffSmoothed.getCurrentValue());
    const float q      = juce::jlimit (0.2f, 4.0f, outputLpfQSmoothed.getCurrentValue());
    outputLpf.setCutoffFrequency (cutoff);
    outputLpf.setResonance (q);
}

void FluteSynthAudioProcessor::updateOutputEq()
{
    if (lastSampleRate <= 0.0)
        return;

    auto clamp = PresetModel::clamp;
    for (size_t i = 0; i < outputEqCfg.bands.size(); ++i)
    {
        const auto& b = outputEqCfg.bands[i];
        const float freq = clamp (b.freq, 40.0f, 16000.0f);
        const float q = clamp (b.q, 0.3f, 6.0f);
        const float gainDb = clamp (b.gainDb, -18.0f, 18.0f);
        outputEqFilters[i].coefficients = juce::dsp::IIR::Coefficients<float>::makePeakFilter (
            lastSampleRate, freq, q, juce::Decibels::decibelsToGain (gainDb));
    }
}

void FluteSynthAudioProcessor::prepareBrightnessFilters()
{
    const int numCh = juce::jmax (1, getTotalNumOutputChannels());
    brightnessFilters.resize ((size_t) numCh);
    juce::dsp::ProcessSpec spec;
    spec.sampleRate = lastSampleRate;
    spec.maximumBlockSize = mainSpec.maximumBlockSize;
    spec.numChannels = (juce::uint32) numCh;
    for (auto& f : brightnessFilters)
    {
        f.reset();
        f.prepare (spec);
    }
    brightnessNumChannels = numCh;
    updateBrightnessFilters (0.0f);
}

void FluteSynthAudioProcessor::updateBrightnessFilters (float targetDb)
{
    if (lastSampleRate <= 0.0 || brightnessFilters.empty())
        return;

    const float limitedDb = juce::jlimit (-12.0f, brightnessMaxDb, targetDb);
    auto coeff = juce::dsp::IIR::Coefficients<float>::makeHighShelf (
        lastSampleRate,
        juce::jlimit (800.0f, 12000.0f, brightnessCutoffHz),
        juce::jlimit (0.2f, 4.0f, brightnessQ),
        juce::Decibels::decibelsToGain (limitedDb));

    for (auto& f : brightnessFilters)
        f.coefficients = coeff;
    brightnessCurrentDb = limitedDb;
}

void FluteSynthAudioProcessor::updateDamperCoeffs()
{
    if (lastSampleRate <= 0.0) return;
    float tauSamples = (float) (damperCfg.smoothMs * 0.001 * lastSampleRate);
    damperSmoothCoeff = tauSamples > 1.0f ? (1.0f - std::exp (-1.0f / juce::jmax (1.0f, tauSamples))) : 1.0f;
    damperSoftenSamples = (int) std::round (damperCfg.softenMs * 0.001 * lastSampleRate);
    damperSoftenA = std::exp (-2.0f * juce::MathConstants<float>::pi * juce::jlimit (40.0f, 8000.0f, damperCfg.softenHz) / (float) juce::jmax (20.0, lastSampleRate));
    for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
            v->setDamperParams (damperCfg);
}

void FluteSynthAudioProcessor::updateMicProcessors()
{
    if (! prepared || lastSampleRate <= 0.0)
        return;

    micSpec.sampleRate = lastSampleRate;
    micSpec.maximumBlockSize = mainSpec.maximumBlockSize;
    micSpec.numChannels = (juce::uint32) juce::jmax (1, getTotalNumOutputChannels());
    micMaxDelaySamples = (int) std::round (lastSampleRate * 0.05); // up to ~50 ms

    for (auto& st : micState)
    {
        for (int ch = 0; ch < 2; ++ch)
        {
            st.delay[ch].reset();
            st.delay[ch].prepare (micSpec);
            st.delay[ch].setMaximumDelayInSamples ((size_t) juce::jmax (8, micMaxDelaySamples));
            st.delay[ch].setDelay (0.0f);
            st.lowShelf[ch].reset();
            st.lowShelf[ch].prepare (micSpec);
            st.highShelf[ch].reset();
            st.highShelf[ch].prepare (micSpec);
        }
        st.delaySamples = 0.0f;
        st.gainLin = 1.0f;
    }
    micReady = true;
}

void FluteSynthAudioProcessor::applyMicMix (juce::AudioBuffer<float>& buffer)
{
    if (! micReady || buffer.getNumChannels() == 0)
        return;

    const int numCh = buffer.getNumChannels();
    const int n = buffer.getNumSamples();
    const float sr = (float) lastSampleRate;
    if (sr <= 0.0f)
        return;

    auto micConfigs = std::array<PresetModel::Mic,3>{ micCfg.close, micCfg.player, micCfg.room };
    auto blend = micCfg.blend;
    float bsum = blend[0] + blend[1] + blend[2];
    if (bsum <= 1.0e-6f)
        blend = { 1.0f, 0.0f, 0.0f };
    else
        for (float& b : blend) b /= bsum;

    // Calculate makeup gain to compensate for mic gain attenuation
    // Without this, blending mics with negative gain_db values causes overall level loss
    float totalLinGain = 0.0f;
    for (int micIdx = 0; micIdx < 3; ++micIdx)
    {
        const float w = blend[(size_t) micIdx];
        if (w > 1.0e-4f)
            totalLinGain += juce::Decibels::decibelsToGain (micConfigs[(size_t) micIdx].gainDb) * w;
    }
    const float micMakeupGain = (totalLinGain > 1.0e-4f) ? (1.0f / totalLinGain) : 1.0f;

    // Fast path: close-only, no delay/EQ
    const auto& closeCfg = micConfigs[0];
    if (blend[0] > 0.999f && blend[1] < 1.0e-4f && blend[2] < 1.0e-4f
        && std::abs (closeCfg.delayMs) < 1.0e-4f
        && std::abs (closeCfg.lowShelfDb) < 1.0e-4f
        && std::abs (closeCfg.highShelfDb) < 1.0e-4f)
    {
        // No makeup needed for close-only (micMakeupGain already accounts for close gain_db)
        buffer.applyGain (juce::Decibels::decibelsToGain (closeCfg.gainDb) * micMakeupGain);
        return;
    }

    if (micScratch.getNumChannels() != numCh || micScratch.getNumSamples() != n)
        micScratch.setSize (numCh, n, false, false, true);
    micScratch.clear();

    for (int micIdx = 0; micIdx < 3; ++micIdx)
    {
        const float w = blend[(size_t) micIdx];
        if (w <= 1.0e-4f)
            continue;

        const auto& cfg = micConfigs[(size_t) micIdx];
        auto& st = micState[(size_t) micIdx];

        st.delaySamples = juce::jlimit (0.0f, (float) micMaxDelaySamples, cfg.delayMs * 0.001f * sr);
        for (int ch = 0; ch < juce::jmin (numCh, 2); ++ch)
            st.delay[ch].setDelay (st.delaySamples);

        const float lsFreq = juce::jlimit (100.0f, 8000.0f, cfg.shelfFreq);
        const float hsFreq = juce::jlimit (500.0f, 12000.0f, cfg.shelfFreq);
        auto lsCoeff = juce::dsp::IIR::Coefficients<float>::makeLowShelf (lastSampleRate, lsFreq, 0.7071f,
                                                                           juce::Decibels::decibelsToGain (cfg.lowShelfDb));
        auto hsCoeff = juce::dsp::IIR::Coefficients<float>::makeHighShelf (lastSampleRate, hsFreq, 0.7071f,
                                                                            juce::Decibels::decibelsToGain (cfg.highShelfDb));
        for (int ch = 0; ch < juce::jmin (numCh, 2); ++ch)
        {
            st.lowShelf[ch].coefficients  = lsCoeff;
            st.highShelf[ch].coefficients = hsCoeff;
        }
        st.gainLin = juce::Decibels::decibelsToGain (cfg.gainDb) * w;

        for (int ch = 0; ch < numCh; ++ch)
        {
            const int stateIdx = juce::jmin (ch, 1);
            auto* dst = micScratch.getWritePointer (ch);
            const auto* src = buffer.getReadPointer (ch);
            for (int i = 0; i < n; ++i)
            {
                float s = st.delay[stateIdx].popSample (0);
                st.delay[stateIdx].pushSample (0, src[i]);
                if (st.lowShelf[stateIdx].coefficients != nullptr)
                    s = st.lowShelf[stateIdx].processSample (s);
                if (st.highShelf[stateIdx].coefficients != nullptr)
                    s = st.highShelf[stateIdx].processSample (s);
                dst[i] += s * st.gainLin;
            }
        }
    }

    buffer.makeCopyOf (micScratch, true);
    
    // Apply makeup gain to compensate for mic blend attenuation
    buffer.applyGain (micMakeupGain);
}
void FluteSynthAudioProcessor::processBlock (juce::AudioBuffer<float>& buffer, juce::MidiBuffer& midi)
{
    juce::ScopedNoDenormals noDenormals;

    // Guard against hosts calling before prepareToPlay.
    if (! prepared || lastSampleRate <= 0.0)
    {
        buffer.clear();
        return;
    }

    const int numCh = juce::jmax (1, buffer.getNumChannels());
    const int numSamples = buffer.getNumSamples();
    auto ensureScratch = [numSamples] (juce::AudioBuffer<float>& buf, int channels)
    {
        if (buf.getNumChannels() != channels || buf.getNumSamples() != numSamples)
            buf.setSize (channels, numSamples, false, false, true);
        buf.clear();
    };
    const int maxPredelaySamples = (int) std::ceil (lastSampleRate * 0.020);
    const int minPredelayCapacity = maxPredelaySamples + numSamples + 2;
    if (predelayCapacitySamples < minPredelayCapacity)
    {
        predelayCapacitySamples = minPredelayCapacity;
        predelayBuf.assign ((size_t) predelayCapacitySamples, 0.0f);
        predelayWrite = 0;
    }

    auto reverbParamsEqual = [] (const juce::Reverb::Parameters& a, const juce::Reverb::Parameters& b)
    {
        const float eps = 1.0e-4f;
        return std::abs (a.roomSize   - b.roomSize)   < eps
            && std::abs (a.damping    - b.damping)    < eps
            && std::abs (a.wetLevel   - b.wetLevel)   < eps
            && std::abs (a.dryLevel   - b.dryLevel)   < eps
            && std::abs (a.width      - b.width)      < eps
            && std::abs (a.freezeMode - b.freezeMode) < eps;
    };
    auto resetPostState = [this]()
    {
        postVaLp1.reset();  postVaLp2.reset();
        postPmLp1.reset();  postPmLp2.reset();
        postPm2Lp1.reset(); postPm2Lp2.reset();
        tiltLow.reset();    tiltHigh.reset();
        outputLpf.reset();
        for (auto& f : outputEqFilters)
            f.reset();
        breathBp.reset();
        for (int i = 0; i < 2; ++i) formant[i].f.reset();
        soundboardReverb.reset();
        soundboardConvolution.reset();
        soundboardConvolutionDs.reset();
        soundboardIrDirty = true;
        soundboardIrLastT60 = 0.0f;
        soundboardIrLastDamp = 0.0f;
        pedalReverb.reset();
        sympReverb.reset();
        postReverb.reset();
        soundboardParamsValid = false;
        pedalReverbParamsValid = false;
        sympParamsValid = false;
        postReverbParamsValid = false;
        std::fill (predelayBuf.begin(), predelayBuf.end(), 0.0f);
        tiltReady = (tiltLow.coefficients != nullptr && tiltHigh.coefficients != nullptr);
    };

    if (pendingStateReset && ! anyVoiceActive())
    {
        resetPostState();
        pendingStateReset = false;
    }

    if (auto* vol = apvts.getRawParameterValue (ParamIDs::masterVolume))
        masterVolumeLin = juce::jlimit (0.0f, 2.0f, vol->load());
    // Minimum note duration: pitch-dependent, fixed milliseconds (tempo-independent).
    // FIX: Drastically reduced minimum durations to allow very short staccato notes
    // Previous values (240-960ms) forced notes to play much longer than intended
    const double minLowMs = 0.0;      // Was 240.0 - no forced minimum
    const double minMidLowMs = 0.0;   // Was 480.0 - no forced minimum
    const double minMidHighMs = 0.0;  // Was 720.0 - no forced minimum
    const double minHighMs = 0.0;     // Was 960.0 - no forced minimum
    const int minNoteLow = (int) std::round (minLowMs * 0.001 * lastSampleRate);
    const int minNoteMidLow = (int) std::round (minMidLowMs * 0.001 * lastSampleRate);
    const int minNoteMidHigh = (int) std::round (minMidHighMs * 0.001 * lastSampleRate);
    const int minNoteHigh = (int) std::round (minHighMs * 0.001 * lastSampleRate);
    const int split1 = 36; // C2 and below
    const int split2 = 48; // C3 and below
    const int split3 = DebugToggles::kEnablePm2MinDurationC4Split ? 60 : 127; // C4 split optional
    pm2Synth.setMinNoteDurationRanges (minNoteLow, minNoteMidLow, minNoteMidHigh, minNoteHigh,
                                       split1, split2, split3);

    // Apply any pending preset reset on the audio thread to avoid GUI/DSP races.
    if (const int pendingPreset = pendingEmbeddedPresetIndex.exchange (-1, std::memory_order_acq_rel);
        pendingPreset >= 0)
    {
        if (! embeddedPresetLoaded.load())
            loadEmbeddedPresetModel();

        const int numPresets = (int) embeddedPresets.size();
        if (embeddedPresetLoaded.load() && numPresets > 0)
        {
            const int presetIdx = juce::jlimit (0, numPresets - 1, pendingPreset);
            activeEmbeddedPresetIndex.store (presetIdx, std::memory_order_release);

            // Stop current voices to avoid artifacts when parameters jump.
            synth.allNotesOff (0, true);
            pmSynth.allNotesOff (0, true);
            pm2Synth.allNotesOff (0, true);

            applyPresetToParameters (embeddedPresets[(size_t) presetIdx].model);
            pendingStateReset = true;
            if (! anyVoiceActive())
            {
                resetPostState();
                pendingStateReset = false;
            }
        }
    }

    buffer.clear();
    syncExtendedParamsFromAPVTS();
    const float outputGainStart = outputGainLinSmoothed.getCurrentValue();
    if (numSamples > 0)
    {
        pm2GainLinSmoothed.skip (numSamples);
        outputGainLinSmoothed.skip (numSamples);
        postCutoffHzSmoothed.skip (numSamples);
        postQSmoothed.skip (numSamples);
        postTiltDbSmoothed.skip (numSamples);
        outputLpfCutoffSmoothed.skip (numSamples);
        outputLpfQSmoothed.skip (numSamples);
    }
    const float outputGainEnd = outputGainLinSmoothed.getCurrentValue();
    pm2GainLin = pm2GainLinSmoothed.getCurrentValue();
    outputGainLin = outputGainEnd;
    updatePostFiltersSmoothed();
    updateOutputLpf();
    
    // FIX #1 & #4: Clear shared buses once at block start (not per segment)
    // This ensures all voices can read/write with consistent block-relative indices
    couplingBus.begin (numSamples);
    sympBus.begin (numSamples);

    // detect note-on/off (for hammer trigger + filter keytracking + pedal state) and apply velocity curve shaping
    struct MidiEvent { juce::MidiMessage msg; int pos { 0 }; };
    std::vector<MidiEvent> events;
    events.reserve ((size_t) midi.getNumEvents());
    std::vector<int> splitPoints;
    splitPoints.reserve ((size_t) midi.getNumEvents() + 2);
    splitPoints.push_back (0);
    splitPoints.push_back (numSamples);

    int noteOnCount = 0;
    int noteOffCount = 0;
    int cc64Count = 0;
    int otherCount = 0;
    int firstEventPos = -1;
    int lastEventPos = -1;
    for (const auto meta : midi)
    {
        auto m = meta.getMessage();
        if (m.isNoteOn())
        {
            // FIX: getVelocity() returns 0-127 (uint8), NOT 0.0-1.0!
            // Must normalize by dividing by 127
            float vel = juce::jlimit<float> (0.0f, 1.0f, (float) m.getVelocity() / 127.0f);
            if (velocityFixed)
                vel = 1.0f;
            else
                vel = std::pow (vel, juce::jmax (0.1f, velocityGamma));
            vel = juce::jlimit (0.0f, 1.0f, vel);
            m = juce::MidiMessage::noteOn (m.getChannel(), m.getNoteNumber(), vel);
            ++noteOnCount;
        }
        else if (m.isNoteOff())
        {
            ++noteOffCount;
        }
        else if (m.isController())
        {
            if (m.getControllerNumber() == 64)
                ++cc64Count;
            else
                ++otherCount;
        }
        else
        {
            ++otherCount;
        }
        const int clampedPos = juce::jlimit (0, juce::jmax (0, numSamples - 1), meta.samplePosition);
        if (firstEventPos < 0)
            firstEventPos = clampedPos;
        lastEventPos = clampedPos;
        events.push_back (MidiEvent { m, clampedPos });
        splitPoints.push_back (clampedPos);
    }

    std::stable_sort (events.begin(), events.end(),
                      [] (const MidiEvent& a, const MidiEvent& b) { return a.pos < b.pos; });
    std::sort (splitPoints.begin(), splitPoints.end());
    splitPoints.erase (std::unique (splitPoints.begin(), splitPoints.end()), splitPoints.end());

    auto smoothstep = [] (float t)
    {
        t = juce::jlimit (0.0f, 1.0f, t);
        return t * t * (3.0f - 2.0f * t);
    };

    const float sustainHysteresis = 0.08f;
    const float sustainOnThresh = juce::jlimit (0.0f, 1.0f, pedalCfg.sustainThresh);
    const float sustainOffThresh = juce::jmax (pedalCfg.halfThresh, sustainOnThresh - sustainHysteresis);

    const bool usePM  = (currentEngine == "pm")  || (currentEngine == "hybrid");
    const bool usePM2 = (currentEngine == "pm2") || (currentEngine == "hybrid");
    const bool useVA  = (currentEngine == "va")  || (currentEngine == "hybrid");
    if (currentEngine == "hybrid")
    {
        if (useVA)  ensureScratch (hybridVaBuf, numCh);
        if (usePM)  ensureScratch (hybridPmBuf, numCh);
        if (usePM2) ensureScratch (hybridPm2Buf, numCh);
    }

    auto applyPostLpfSegment = [] (juce::AudioBuffer<float>& buf,
                                   juce::dsp::StateVariableTPTFilter<float>& f1,
                                   juce::dsp::StateVariableTPTFilter<float>& f2,
                                   int start, int num)
    {
        if (num <= 0)
            return;
        juce::dsp::AudioBlock<float> block (buf);
        auto sub = block.getSubBlock ((size_t) start, (size_t) num);
        juce::dsp::ProcessContextReplacing<float> ctx (sub);
        f1.process (ctx);
        f2.process (ctx);
    };

    auto clearSegment = [] (juce::AudioBuffer<float>& buf, int start, int num)
    {
        for (int ch = 0; ch < buf.getNumChannels(); ++ch)
            buf.clear (ch, start, num);
    };
    auto applyGainSegment = [] (juce::AudioBuffer<float>& buf, float gain, int start, int num)
    {
        if (std::abs (gain - 1.0f) < 1.0e-6f || num <= 0)
            return;
        for (int ch = 0; ch < buf.getNumChannels(); ++ch)
            buf.applyGain (ch, start, num, gain);
    };
    auto applyGainRampSegment = [] (juce::AudioBuffer<float>& buf, float startGain, float endGain, int start, int num)
    {
        if (num <= 0)
            return;
        if (std::abs (startGain - endGain) < 1.0e-6f)
        {
            if (std::abs (startGain - 1.0f) < 1.0e-6f)
                return;
            for (int ch = 0; ch < buf.getNumChannels(); ++ch)
                buf.applyGain (ch, start, num, startGain);
            return;
        }
        for (int ch = 0; ch < buf.getNumChannels(); ++ch)
            buf.applyGainRamp (ch, start, num, startGain, endGain);
    };
    auto applySoftClipSegment = [] (juce::AudioBuffer<float>& buf, int start, int num, float drive)
    {
        if (num <= 0)
            return;
        const float k = juce::jlimit (0.5f, 3.0f, drive);
        const float norm = 1.0f / std::tanh (k);
        for (int ch = 0; ch < buf.getNumChannels(); ++ch)
        {
            auto* x = buf.getWritePointer (ch, start);
            for (int i = 0; i < num; ++i)
                x[i] = std::tanh (k * x[i]) * norm;
        }
    };
    auto applyDeclickSegment = [&smoothstep] (juce::AudioBuffer<float>& buf, int start, int num, int declickSamples)
    {
        if (declickSamples <= 0 || num <= 0)
            return;
        const int rampLen = juce::jmin (num, declickSamples);
        for (int ch = 0; ch < buf.getNumChannels(); ++ch)
        {
            auto* x = buf.getWritePointer (ch, start);
            for (int i = 0; i < rampLen; ++i)
            {
                const float t = (float) (i + 1) / (float) rampLen;
                const float g = smoothstep (t);
                x[i] *= g;
            }
        }
    };
    auto applyDeclickOutSegment = [&smoothstep] (juce::AudioBuffer<float>& buf, int start, int num, int declickSamples)
    {
        if (declickSamples <= 0 || num <= 0)
            return;
        const int rampLen = juce::jmin (num, declickSamples);
        for (int ch = 0; ch < buf.getNumChannels(); ++ch)
        {
            auto* x = buf.getWritePointer (ch, start);
            for (int i = 0; i < rampLen; ++i)
            {
                const float t = (float) (i + 1) / (float) rampLen;
                const float g = smoothstep (1.0f - t);
                x[i] *= g;
            }
        }
    };

    auto countActivePm2Voices = [&]()
    {
        int active = 0;
        for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
            if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
                if (v->isActive())
                    ++active;
        return active;
    };

    std::size_t eventIdx = 0;
    for (size_t s = 0; s + 1 < splitPoints.size(); ++s)
    {
        const int segStart = splitPoints[s];
        const int segEnd = splitPoints[s + 1];
        const int segLen = segEnd - segStart;
        if (segLen <= 0)
            continue;

        // CPU optimisation: earlier economy mode activation under high polyphony
        const int activeVoicesNow = countActivePm2Voices();
        const bool highPolyMode = activeVoicesNow >= 4;
        if (pm2EconomyMode != highPolyMode)
        {
            pm2EconomyMode = highPolyMode;
            for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
                if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
                {
                    v->setEconomyMode (pm2EconomyMode);
                    v->setHighPolyMode (pm2EconomyMode);
                }
        }
        {
            const int maxVoices = 12;
            const float minScale = 0.6f;
            float polyScale = 1.0f;
            if (activeVoicesNow > 4)
            {
                const float t = juce::jlimit (0.0f, 1.0f, (float) (activeVoicesNow - 4) / (float) (maxVoices - 4));
                polyScale = 1.0f + t * (minScale - 1.0f);
            }
            for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
                if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
                    v->setPolyphonyScale (polyScale);
        }

        bool sustainChanged = false;
        bool sustainUpdatePending = false;
        float keyOffVelAcc = 0.0f;
        float releaseThumpAcc = 0.0f;
        bool sawNoteOn = false;
        int noteNumber = 0;
        float noteOnVel = 0.0f;
        juce::MidiBuffer midiSegment;
        juce::MidiBuffer midiSegmentPm2;

        while (eventIdx < events.size() && events[eventIdx].pos < segStart)
            ++eventIdx;

        // FIX: Count note-ons at this position FIRST, then preallocate all voices at once
        // This prevents JUCE's internal voice stealing from interfering with chords
        // Also include repeated same-note note-ons so we allow overlap instead of hard retrigger.
        {
            int noteOnCount = 0;
            if (usePM2)
            {
                size_t peekIdx = eventIdx;
                while (peekIdx < events.size() && events[peekIdx].pos == segStart)
                {
                    const auto& msg = events[peekIdx].msg;
                    if (msg.isNoteOn())
                        ++noteOnCount;
                    ++peekIdx;
                }
            }
            if (noteOnCount > 0)
                pm2Synth.preallocateVoicesForChord (noteOnCount);
        }

        while (eventIdx < events.size() && events[eventIdx].pos == segStart)
        {
            const int eventPos = events[eventIdx].pos;
            auto m = events[eventIdx].msg;
            const bool isAllowedController = m.isController()
                && (m.getControllerNumber() == 64 || m.getControllerNumber() == 67);
            const bool allowToPass = m.isNoteOn() || m.isNoteOff() || isAllowedController;
            if (m.isController())
            {
                if (m.getControllerNumber() == 64) // sustain
                {
                    sustainValue = juce::jlimit (0.0f, 1.0f, m.getControllerValue() / 127.0f);
                    sustainUpdatePending = true;
                }
                else if (m.getControllerNumber() == 67) // soft / una corda
                {
                    softPedalDown = m.getControllerValue() >= 32;
                    for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
                        if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
                            v->setSoftPedal (softPedalDown, unaCfg);
                }
            }
            if (m.isNoteOn())
            {
                sawNoteOn = true;
                noteNumber = m.getNoteNumber();
                // FIX: getVelocity() returns 0-127, must normalize by dividing by 127
                noteOnVel = juce::jlimit (0.0f, 1.0f, (float) m.getVelocity() / 127.0f);
                // Note: preallocateVoicesForChord was already called above for all note-ons
                updatePostFiltersForNote (noteNumber);
            }
            else if (m.isNoteOff())
            {
                // FIX: getVelocity() returns 0-127, must normalize by dividing by 127
                float relVel = juce::jlimit (0.0f, 1.0f, (float) m.getVelocity() / 127.0f);
                if (keyOffEnabled)
                {
                    float amt = keyOffLevel * (keyOffVelScale ? juce::jlimit (0.2f, 1.0f, relVel) : 1.0f);
                    keyOffVelAcc = juce::jlimit (0.0f, 4.0f, keyOffVelAcc + amt);
                }
                if (releaseThumpEnabled && ! sustainPedalDown)
                {
                    float amt = releaseThumpLevel * (keyOffVelScale ? juce::jlimit (0.2f, 1.0f, relVel) : 1.0f);
                    releaseThumpAcc = juce::jlimit (0.0f, 4.0f, releaseThumpAcc + amt);
                }
            }

            if (allowToPass)
            {
                if (usePM2)
                    midiSegmentPm2.addEvent (m, eventPos);
                midiSegment.addEvent (m, eventPos);
            }
            ++eventIdx;
        }

        if (sawNoteOn)
        {
            lastVelocityNorm = noteOnVel;
            if (hammerEnabled)
            {
                hammerActive = true;
                hammerEnv = hammerLevel;
            }
        }

        if (keyOffVelAcc > 0.0f)
            keyOffEnv = juce::jlimit (0.0f, 4.0f, keyOffEnv + keyOffVelAcc);
        if (releaseThumpAcc > 0.0f)
            releaseThumpEnv = juce::jlimit (0.0f, 4.0f, releaseThumpEnv + releaseThumpAcc);

        float sustainValuePrev = sustainValueSmoothed.getCurrentValue();
        sustainValueSmoothed.setTargetValue (sustainValue);
        if (segLen > 0)
            sustainValueSmoothed.skip (segLen);
        float sustainValueSmooth = sustainValueSmoothed.getCurrentValue();
        if (DebugToggles::kDisableSustainPedal)
        {
            sustainValue = 0.0f;
            sustainValuePrev = 0.0f;
            sustainValueSmooth = 0.0f;
            sustainValueSmoothed.setTargetValue (0.0f);
            sustainPedalDown = false;
        }
        {
            const bool newDown = sustainPedalDown ? (sustainValueSmooth >= sustainOffThresh)
                                                  : (sustainValueSmooth >= sustainOnThresh);
            if (newDown != sustainPedalDown)
            {
                sustainPedalDown = newDown;
                sustainChanged = true;
                const int activeVoices = countActivePm2Voices();
                const int declickSamples = juce::jlimit (96, 384, 96 + activeVoices * 24);
                pm2Synth.requestDeclickOut (declickSamples);
                pm2Synth.requestDeclick (declickSamples);
                if (pedalThumpEnabled)
                {
                    const float changeAmt = std::abs (sustainValueSmooth - sustainValuePrev);
                    const float scale = juce::jlimit (0.2f, 1.0f, changeAmt > 0.0001f ? changeAmt : (newDown ? sustainValueSmooth : sustainValuePrev));
                    pedalThumpEnv = juce::jlimit (0.0f, 4.0f, pedalThumpEnv + pedalThumpLevel * scale);
                }
            }
            else if (sustainUpdatePending && pedalThumpEnabled)
            {
                const float changeAmt = std::abs (sustainValueSmooth - sustainValuePrev);
                const float scale = juce::jlimit (0.1f, 0.6f, changeAmt);
                if (scale > 1.0e-4f)
                    pedalThumpEnv = juce::jlimit (0.0f, 4.0f, pedalThumpEnv + pedalThumpLevel * scale);
            }
        }

        float damperLiftBlock = damperLift;
        if (sustainPedalDown) damperLiftBlock = 1.0f;
        else if (sustainValueSmooth <= pedalCfg.halfThresh) damperLiftBlock = 0.0f;
        else
        {
            const float span = juce::jmax (0.001f, pedalCfg.sustainThresh - pedalCfg.halfThresh);
            const float t = (sustainValueSmooth - pedalCfg.halfThresh) / span;
            damperLiftBlock = smoothstep (t);
        }

        const float sustainReleaseScale = juce::jlimit (1.0f, 4.0f, pedalCfg.sustainReleaseScale);
        const float releaseScaleTarget = sustainPedalDown ? sustainReleaseScale
                                                          : ((sustainValueSmooth >= pedalCfg.halfThresh) ? halfReleaseScale : 1.0f);
        sustainReleaseScaleSmoothed.setTargetValue (releaseScaleTarget);
        if (segLen > 0)
            sustainReleaseScaleSmoothed.skip (segLen);
        const float releaseScale = sustainReleaseScaleSmoothed.getCurrentValue();
        for (int i = 0; i < pmSynth.getNumVoices(); ++i)
            if (auto* v = dynamic_cast<PmVoice*> (pmSynth.getVoice (i)))
                v->setReleaseScale (baseRelease, releaseScale);
        for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
            if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
                v->setReleaseScale (baseRelease, releaseScale);
        if (sustainChanged)
        {
            for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
                if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
                    v->setSustainPedalDown (sustainPedalDown);
        }
        damperLift = damperLiftBlock;
        for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
            if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
                v->setDamperLift (damperLiftBlock);

        if (currentEngine == "pm")
        {
            pmSynth.renderNextBlock (buffer, midiSegment, segStart, segLen);
            if (DebugToggles::kEnableGlobalFilters)
                applyPostLpfSegment (buffer, postPmLp1, postPmLp2, segStart, segLen);
        }
        else if (currentEngine == "pm2")
        {
            // FIX #4: Buses are now cleared once at block start, not per segment
            pm2Synth.renderNextBlock (buffer, midiSegmentPm2, segStart, segLen);
            applyDeclickOutSegment (buffer, segStart, segLen, pm2Synth.consumeDeclickOutSamples());
            applyDeclickSegment (buffer, segStart, segLen, pm2Synth.consumeDeclickSamples());
            applyGainSegment (buffer, pm2GainLin, segStart, segLen);
            // FIX #2: Smoothed polyphony compensation to prevent gain jumps
            {
                int activeVoices = 0;
                for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
                    if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
                        if (v->isActive())
                            ++activeVoices;
                // Gentle linear compensation: 100% at 1 voice, 90% at 4, 80% at 7, 70% floor at 10+
                const float rawComp = (activeVoices > 1) ? (1.0f - ((float) (activeVoices - 1)) / 140.0f) : 1.0f;
                polyCompTarget = juce::jmax (0.95f, rawComp);
                // Smooth towards target over ~5-10ms to avoid clicks (closed-form per segment)
                if (segLen > 0)
                {
                    const float decay = std::pow (1.0f - polyCompSmoothCoeff, (float) segLen);
                    polyCompSmoothed = polyCompTarget + (polyCompSmoothed - polyCompTarget) * decay;
                }
                if (std::abs (polyCompSmoothed - 1.0f) > 1.0e-4f)
                    applyGainSegment (buffer, polyCompSmoothed, segStart, segLen);
            }
            {
                float targetGain = 1.0f;
                if (sustainPedalDown && pedalCfg.sustainGainDb > 0.01f)
                {
                    const float sustainGainLin = juce::Decibels::decibelsToGain (pedalCfg.sustainGainDb);
                    targetGain = mixLinear (1.0f, sustainGainLin, sustainValueSmooth);
                }
                sustainGainLinSmoothed.setTargetValue (targetGain);
                const float startGain = sustainGainLinSmoothed.getCurrentValue();
                sustainGainLinSmoothed.skip (segLen);
                const float endGain = sustainGainLinSmoothed.getCurrentValue();
                if (std::abs (startGain - 1.0f) > 1.0e-4f || std::abs (endGain - 1.0f) > 1.0e-4f)
                    applyGainRampSegment (buffer, startGain, endGain, segStart, segLen);
            }
            if (pm2GainDb > 0.01f)
                applySoftClipSegment (buffer, segStart, segLen, 1.6f);
            if (DebugToggles::kEnableGlobalFilters)
                applyPostLpfSegment (buffer, postPm2Lp1, postPm2Lp2, segStart, segLen);
        }
        else if (currentEngine == "va")
        {
            synth.renderNextBlock (buffer, midiSegment, segStart, segLen);
            if (DebugToggles::kEnableGlobalFilters)
                applyPostLpfSegment (buffer, postVaLp1, postVaLp2, segStart, segLen);
        }
        else // hybrid
        {
            if (useVA)
            {
                clearSegment (hybridVaBuf, segStart, segLen);
                synth.renderNextBlock (hybridVaBuf, midiSegment, segStart, segLen);
                if (DebugToggles::kEnableGlobalFilters)
                    applyPostLpfSegment (hybridVaBuf, postVaLp1, postVaLp2, segStart, segLen);
            }

            if (usePM)
            {
                clearSegment (hybridPmBuf, segStart, segLen);
                pmSynth.renderNextBlock (hybridPmBuf, midiSegment, segStart, segLen);
                if (DebugToggles::kEnableGlobalFilters)
                    applyPostLpfSegment (hybridPmBuf, postPmLp1, postPmLp2, segStart, segLen);
            }

            if (usePM2)
            {
                clearSegment (hybridPm2Buf, segStart, segLen);
                // FIX #4: Buses are now cleared once at block start, not per segment
                pm2Synth.renderNextBlock (hybridPm2Buf, midiSegmentPm2, segStart, segLen);
                applyDeclickOutSegment (hybridPm2Buf, segStart, segLen, pm2Synth.consumeDeclickOutSamples());
                applyDeclickSegment (hybridPm2Buf, segStart, segLen, pm2Synth.consumeDeclickSamples());
                applyGainSegment (hybridPm2Buf, pm2GainLin, segStart, segLen);
                // FIX #2: Smoothed polyphony compensation to prevent gain jumps
                {
                    int activeVoices = 0;
                    for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
                        if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
                            if (v->isActive())
                                ++activeVoices;
                    // Gentle linear compensation: 100% at 1 voice, 90% at 4, 80% at 7, 70% floor at 10+
                    const float rawComp = (activeVoices > 1) ? (1.0f - ((float) (activeVoices - 1)) / 140.0f) : 1.0f;
                    polyCompTarget = juce::jmax (0.95f, rawComp);
                    if (segLen > 0)
                    {
                        const float decay = std::pow (1.0f - polyCompSmoothCoeff, (float) segLen);
                        polyCompSmoothed = polyCompTarget + (polyCompSmoothed - polyCompTarget) * decay;
                    }
                    if (std::abs (polyCompSmoothed - 1.0f) > 1.0e-4f)
                        applyGainSegment (hybridPm2Buf, polyCompSmoothed, segStart, segLen);
                }
                {
                    float targetGain = 1.0f;
                    if (sustainPedalDown && pedalCfg.sustainGainDb > 0.01f)
                    {
                        const float sustainGainLin = juce::Decibels::decibelsToGain (pedalCfg.sustainGainDb);
                    targetGain = mixLinear (1.0f, sustainGainLin, sustainValueSmooth);
                    }
                    sustainGainLinSmoothed.setTargetValue (targetGain);
                    const float startGain = sustainGainLinSmoothed.getCurrentValue();
                    sustainGainLinSmoothed.skip (segLen);
                    const float endGain = sustainGainLinSmoothed.getCurrentValue();
                    if (std::abs (startGain - 1.0f) > 1.0e-4f || std::abs (endGain - 1.0f) > 1.0e-4f)
                        applyGainRampSegment (hybridPm2Buf, startGain, endGain, segStart, segLen);
                }
                if (pm2GainDb > 0.01f)
                    applySoftClipSegment (hybridPm2Buf, segStart, segLen, 1.6f);
                if (DebugToggles::kEnableGlobalFilters)
                    applyPostLpfSegment (hybridPm2Buf, postPm2Lp1, postPm2Lp2, segStart, segLen);
            }

            float wVa = juce::jlimit (0.0f, 1.0f, vaMix);
            float wPm = juce::jlimit (0.0f, 1.0f, pmMix);
            float wPm2 = juce::jlimit (0.0f, 1.0f, pm2Mix);
            float sum = juce::jmax (0.0001f, wVa + wPm + wPm2);
            wVa /= sum; wPm /= sum; wPm2 /= sum;

            for (int chOut = 0; chOut < buffer.getNumChannels(); ++chOut)
            {
                auto* dst = buffer.getWritePointer (chOut, segStart);
                auto* vaP = hybridVaBuf.getReadPointer (juce::jmin (chOut, hybridVaBuf.getNumChannels() - 1), segStart);
                auto* pmP = hybridPmBuf.getReadPointer (juce::jmin (chOut, hybridPmBuf.getNumChannels() - 1), segStart);
                auto* pm2P = hybridPm2Buf.getReadPointer (juce::jmin (chOut, hybridPm2Buf.getNumChannels() - 1), segStart);
                for (int i = 0; i < segLen; ++i)
                    dst[i] += vaP[i] * wVa + pmP[i] * wPm + pm2P[i] * wPm2;
            }
        }
    }

#if JUCE_DEBUG
    static int dbgBlockCounter = 0;
    ++dbgBlockCounter;
    const int eventsCount = (int) events.size();
    const int segmentsCount = (int) splitPoints.size() - 1;
    const bool eventDrift = (eventIdx != events.size());
    const float peak = buffer.getMagnitude (0, buffer.getNumSamples());
    if ((dbgBlockCounter % 200) == 0 || eventsCount > 0 || peak > 1.0e-4f || eventDrift)
    {
        int activePm2 = 0;
        for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
            if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
                if (v->isActive())
                    ++activePm2;

        DBG ("[MusPianoVST] blk=" << dbgBlockCounter
             << " events=" << eventsCount
             << " noteOn=" << noteOnCount
             << " noteOff=" << noteOffCount
             << " cc64=" << cc64Count
             << " other=" << otherCount
             << " segments=" << segmentsCount
             << " pm2Active=" << activePm2
             << " peak=" << peak
             << " firstPos=" << firstEventPos
             << " lastPos=" << lastEventPos
             << " eventDrift=" << (eventDrift ? "YES" : "no"));
    }
#endif

    // Optional shaper applied to VA-only or hybrid paths
    if (currentEngine == "va")
    {
        if (shaperEnabled && shaperDrive > 0.001f)
        {
            const float k = juce::jlimit (0.01f, 3.0f, shaperDrive * 3.0f);
            for (int ch = 0; ch < buffer.getNumChannels(); ++ch)
            {
                auto* x = buffer.getWritePointer (ch);
                for (int i = 0; i < buffer.getNumSamples(); ++i)
                    x[i] = std::tanh (k * x[i]);
            }
        }
    }
    else if (currentEngine == "hybrid")
    {
        if (shaperEnabled && shaperDrive > 0.001f)
        {
            const float k = juce::jlimit (0.01f, 3.0f, shaperDrive * 3.0f);
            for (int ch = 0; ch < buffer.getNumChannels(); ++ch)
            {
                auto* x = buffer.getWritePointer (ch);
                for (int i = 0; i < buffer.getNumSamples(); ++i)
                    x[i] = std::tanh (k * x[i]);
            }
        }
    }

    #if 0
    // --- Hammer transient (additive burst) ---
    if (hammerActive && hammerEnv > 1e-6f)
    {
        const int n = buffer.getNumSamples();
        const int chs = buffer.getNumChannels();

        for (int i = 0; i < n; ++i)
        {
            float w = fastRand01(hammerRng) * 2.0f - 1.0f;  // white ~[-1,1]
            w *= hammerNoise;

            float shaped = DebugToggles::kEnableHammerFilter ? hammerHP.processSample (0, w) : w;
            float s = shaped * hammerEnv;

            for (int ch = 0; ch < chs; ++ch)
            {
                auto* dst = buffer.getWritePointer (ch);
                dst[i] += s;
            }

            hammerEnv *= hammerDecayCoeff;
            if (hammerEnv < 1e-6f)
            {
                hammerEnv = 0.0f;
                hammerActive = false;
                break;
            }
        }
    }
    #endif

    // --- Key-off noise burst ---
    if (keyOffEnabled && keyOffEnv > 1e-6f)
    {
        const int n = buffer.getNumSamples();
        const int chs = buffer.getNumChannels();
        for (int i = 0; i < n; ++i)
        {
            float w = fastRand01 (hammerRng) * 2.0f - 1.0f;
            float shaped = DebugToggles::kEnableKeyOffFilter ? keyOffHP.processSample (0, w) : w;
            float s = shaped * keyOffEnv;
            for (int ch = 0; ch < chs; ++ch)
                buffer.getWritePointer (ch)[i] += s;

            keyOffEnv *= keyOffDecayCoeff;
            if (keyOffEnv < 1e-6f) { keyOffEnv = 0.0f; break; }
        }
    }

    // --- Release thump (dampers hitting strings) ---
    if (releaseThumpEnabled && releaseThumpEnv > 1e-6f)
    {
        const int n = buffer.getNumSamples();
        const int chs = buffer.getNumChannels();
        for (int i = 0; i < n; ++i)
        {
            float w = fastRand01 (hammerRng) * 2.0f - 1.0f;
            float low = DebugToggles::kEnableReleaseThumpFilter ? releaseThumpLP.processSample (0, w) : w;
            float thud = DebugToggles::kEnableReleaseThudFilter ? releaseThudHP.processSample (0, low) : low;
            float s = (low * (1.0f - releaseThudMix) + thud * releaseThudMix) * releaseThumpEnv;
            for (int ch = 0; ch < chs; ++ch)
                buffer.getWritePointer (ch)[i] += s;

            releaseThumpEnv *= releaseThumpDecayCoeff;
            if (releaseThumpEnv < 1e-6f) { releaseThumpEnv = 0.0f; break; }
        }
    }

    // --- Pedal thump (CC64 transitions) ---
    if (pedalThumpEnabled && pedalThumpEnv > 1e-6f)
    {
        const int n = buffer.getNumSamples();
        const int chs = buffer.getNumChannels();
        for (int i = 0; i < n; ++i)
        {
            float w = fastRand01 (hammerRng) * 2.0f - 1.0f;
            float shaped = DebugToggles::kEnablePedalThumpFilter ? pedalThumpLP.processSample (0, w) : w;
            float s = shaped * pedalThumpEnv;
            for (int ch = 0; ch < chs; ++ch)
                buffer.getWritePointer (ch)[i] += s;

            pedalThumpEnv *= pedalThumpDecayCoeff;
            if (pedalThumpEnv < 1e-6f) { pedalThumpEnv = 0.0f; break; }
        }
    }

    // --- Breath noise (post) ---
    if (breathEnabled && breathGainLin > 0.0f)
    {
        ensureScratch (breathScratch, 1);
        float* t = breathScratch.getWritePointer (0);
        static uint32_t rng = 0xBEEFBEEF;
        for (int i = 0; i < buffer.getNumSamples(); ++i)
        {
            rng = 1664525u * rng + 1013904223u;
            t[i] = ((rng >> 8) * (1.0f / 16777216.0f)) * 2.0f - 1.0f;
        }

        if (DebugToggles::kEnableBreathFilter)
        {
            juce::dsp::AudioBlock<float> b (breathScratch);
            juce::dsp::ProcessContextReplacing<float> ctx (b);
            breathBp.process (ctx);
        }

        for (int ch = 0; ch < buffer.getNumChannels(); ++ch)
        {
            auto* dst = buffer.getWritePointer (ch);
            for (int i = 0; i < buffer.getNumSamples(); ++i)
                dst[i] += breathGainLin * t[i];
        }
    }

    // --- Formants (post) --- PARALLEL RESONANCE PEAKS
    // Instead of replacing the signal with bandpass-filtered content,
    // we add resonance peaks in parallel to preserve the full spectrum.
    if (DebugToggles::kEnableFormant)
    {
        for (int k = 0; k < 2; ++k)
        {
            if (! formant[k].enabled) continue;

            // Create a copy for wet/resonance signal
            formantScratch.makeCopyOf (buffer, true);

            juce::dsp::AudioBlock<float> block (formantScratch);
            juce::dsp::ProcessContextReplacing<float> ctx (block);
            formant[k].f.process (ctx);

            // Mix formant resonance back in additively. 0 dB means neutral.
            const float peakGain = formant[k].gainLin - 1.0f;
            if (std::abs (peakGain) < 1.0e-4f)
                continue;
            for (int ch = 0; ch < buffer.getNumChannels(); ++ch)
            {
                auto* dry = buffer.getWritePointer (ch);
                const auto* w = formantScratch.getReadPointer (ch);
                for (int i = 0; i < buffer.getNumSamples(); ++i)
                    dry[i] += w[i] * peakGain;
            }
        }
    }

    // --- Post tone controls: tilt only (LPFs were applied per-engine pre-sum) ---
    if (DebugToggles::kEnableTilt)
    {
        // If host channel count changed after prepareToPlay, re-prepare tilt filters.
        if (buffer.getNumChannels() > 0 && buffer.getNumChannels() != tiltNumChannels)
        {
            juce::dsp::ProcessSpec spec = mainSpec;
            spec.numChannels = (juce::uint32) juce::jmax (1, buffer.getNumChannels());
            tiltLow.reset(); tiltHigh.reset();
            tiltLow.prepare (spec); tiltHigh.prepare (spec);
            tiltNumChannels = buffer.getNumChannels();
            tiltReady = false;
            updatePostFiltersForNote (lastMidiNote);
            auto prepSendHpfDynamic = [this, &spec] (decltype (pedalSendHpf)& f)
            {
                f.reset();
                f.prepare (spec);
                auto coeffs = juce::dsp::IIR::Coefficients<float>::makeHighPass (spec.sampleRate,
                                                                                 sendHpfCutoff,
                                                                                 0.707f);
                if (f.state == nullptr)
                    f.state = coeffs;
                else
                    *f.state = *coeffs;
            };
            prepSendHpfDynamic (pedalSendHpf);
            prepSendHpfDynamic (sympSendHpf);
            prepSendHpfDynamic (soundboardSendHpf);
            {
                juce::dsp::ProcessSpec monoSpec = spec;
                monoSpec.numChannels = 1;
                modalSendHpf.reset();
                modalSendHpf.prepare (monoSpec);
                modalSendHpf.coefficients = juce::dsp::IIR::Coefficients<float>::makeHighPass (monoSpec.sampleRate,
                                                                                               sendHpfCutoff,
                                                                                               0.707f);
            }
            sendHpfNumChannels = buffer.getNumChannels();
            prepareBrightnessFilters();
        }

        juce::dsp::AudioBlock<float> block (buffer);
        juce::dsp::ProcessContextReplacing<float> ctx (block);
        if (std::abs (postTiltDbSmoothed.getCurrentValue()) > 1.0e-4f)
        {
            if (tiltLow.coefficients == nullptr || tiltHigh.coefficients == nullptr)
                updatePostFiltersForNote (lastMidiNote);

            if (tiltLow.coefficients != nullptr && tiltHigh.coefficients != nullptr && lastSampleRate > 0.0 && tiltReady)
            {
                tiltLow.process (ctx);
                tiltHigh.process (ctx);
            }
        }
    }

    // --- Velocity-driven brightness shelf ---
    if (DebugToggles::kEnableBrightness && brightnessEnabled && ! brightnessFilters.empty())
    {
        if (buffer.getNumChannels() != brightnessNumChannels)
            prepareBrightnessFilters();

        const float noteTerm = brightnessNoteSlopeDb * ((float) lastMidiNote - 60.0f) * (1.0f / 24.0f);
        float targetDb = brightnessBaseDb + lastVelocityNorm * brightnessVelSlopeDb + noteTerm;
        targetDb = juce::jlimit (-12.0f, brightnessMaxDb, targetDb);
        brightnessDbSmoothed.setTargetValue (targetDb);
        if (buffer.getNumSamples() > 0)
            brightnessDbSmoothed.skip (buffer.getNumSamples());
        const float currentDb = brightnessDbSmoothed.getCurrentValue();
        if (std::abs (currentDb - brightnessCurrentDb) > 1.0e-4f)
            updateBrightnessFilters (currentDb);

        const int chs = buffer.getNumChannels();
        const int n = buffer.getNumSamples();
        for (int chIdx = 0; chIdx < chs; ++chIdx)
        {
            auto* x = buffer.getWritePointer (chIdx);
            auto& f = brightnessFilters[(size_t) juce::jmin (chIdx, (int) brightnessFilters.size() - 1)];
            for (int i = 0; i < n; ++i)
            {
                if (f.coefficients != nullptr)
                    x[i] = f.processSample (x[i]);
            }
        }
    }

    // CPU optimisation: Lowered threshold from 14 to 8 for earlier effect bypass
    const bool highPolyProcessing = countActivePm2Voices() >= 6;

    // --- Pedal resonance send/return (subtle body) ---
    if (DebugToggles::kEnablePm2PedalResonance && DebugToggles::kEnableReverb
        && ! highPolyProcessing && pedalCfg.resonanceMix > 0.0001f && sustainValue >= pedalCfg.halfThresh)
    {
        const float send = pedalCfg.resonanceSend * sustainValue;
        const float mix  = pedalCfg.resonanceMix * sustainValue;
        if (send > 0.0001f && mix > 0.0001f)
        {
            pedalScratch.makeCopyOf (buffer, true);
            for (int ch = 0; ch < pedalScratch.getNumChannels(); ++ch)
            {
                auto* x = pedalScratch.getWritePointer (ch);
                for (int i = 0; i < pedalScratch.getNumSamples(); ++i)
                    x[i] *= send;
            }

            {
                juce::dsp::AudioBlock<float> wetBlock (pedalScratch);
                juce::dsp::ProcessContextReplacing<float> wetCtx (wetBlock);
                pedalSendHpf.process (wetCtx);
            }

            auto p = pedalReverbParams;
            p.wetLevel = 1.0f;
            p.dryLevel = 0.0f;
            p.roomSize = juce::jlimit (0.0f, 0.4f, p.roomSize); // Limit room size for less wash
            if (! pedalReverbParamsValid || ! reverbParamsEqual (p, pedalReverbParamsApplied))
            {
                pedalReverb.setParameters (p);
                pedalReverbParamsApplied = p;
                pedalReverbParamsValid = true;
            }

            if (pedalScratch.getNumChannels() >= 2)
                pedalReverb.processStereo (pedalScratch.getWritePointer (0), pedalScratch.getWritePointer (1), pedalScratch.getNumSamples());
            else
                pedalReverb.processMono (pedalScratch.getWritePointer (0), pedalScratch.getNumSamples());

            for (int ch = 0; ch < buffer.getNumChannels(); ++ch)
            {
                auto* dry = buffer.getWritePointer (ch);
                auto* ww  = pedalScratch.getWritePointer (ch);
                for (int i = 0; i < buffer.getNumSamples(); ++i)
                    dry[i] = dry[i] * (1.0f - mix) + ww[i] * mix;
            }
        }
    }

    // --- Sympathetic send/return (undamped strings/pedal) ---
    // Allow a scaled amount even without sustain, for controllable sympathetic ringing.
    const float sympPedalScale = sustainPedalDown ? sustainValue : duplexCfg.sympNoPedalScale;
    if (DebugToggles::kEnableReverb && ! highPolyProcessing && duplexCfg.sympMix > 0.0001f && sympPedalScale > 0.0001f)
    {
        const float send = juce::jlimit (0.0f, 1.0f, duplexCfg.sympSend) * sympPedalScale;
        const float mix  = juce::jlimit (0.0f, 1.0f, duplexCfg.sympMix) * sympPedalScale;
        if (send > 0.0001f && mix > 0.0001f)
        {
            sympScratch.makeCopyOf (buffer, true);
            for (int ch = 0; ch < sympScratch.getNumChannels(); ++ch)
            {
                auto* x = sympScratch.getWritePointer (ch);
                for (int i = 0; i < sympScratch.getNumSamples(); ++i)
                    x[i] *= send;
            }

            {
                juce::dsp::AudioBlock<float> wetBlock (sympScratch);
                juce::dsp::ProcessContextReplacing<float> wetCtx (wetBlock);
                sympSendHpf.process (wetCtx);
            }

            auto p = sympParams;
            p.wetLevel = 1.0f;
            p.dryLevel = 0.0f;
            p.roomSize = juce::jlimit (0.0f, 0.3f, p.roomSize); // Smaller room for less wash
            if (! sympParamsValid || ! reverbParamsEqual (p, sympParamsApplied))
            {
                sympReverb.setParameters (p);
                sympParamsApplied = p;
                sympParamsValid = true;
            }

            if (sympScratch.getNumChannels() >= 2)
                sympReverb.processStereo (sympScratch.getWritePointer (0), sympScratch.getWritePointer (1), sympScratch.getNumSamples());
            else
                sympReverb.processMono (sympScratch.getWritePointer (0), sympScratch.getNumSamples());

            for (int ch = 0; ch < buffer.getNumChannels(); ++ch)
            {
                auto* dry = buffer.getWritePointer (ch);
                auto* ww  = sympScratch.getWritePointer (ch);
                for (int i = 0; i < buffer.getNumSamples(); ++i)
                    dry[i] = dry[i] * (1.0f - mix) + ww[i] * mix;
            }
        }
    }

    // --- Modal soundboard (BPF bank + predelay) ---
    const bool useModal = DebugToggles::kEnablePm2ModalSoundboard
                          && (! pmBoardModes.isEmpty()) && (pmBoardMix > 0.0001f) && (pmBoardSend > 0.0001f);
    if (useModal)
    {
        ensureScratch (modalScratch, numCh);
        if (modalDirty || (int) modalModes.size() != pmBoardModes.size())
        {
            modalModes.clear();
            modalModes.reserve ((size_t) pmBoardModes.size());
            for (const auto& m : pmBoardModes)
            {
                modalModes.emplace_back();
                auto& mm = modalModes.back();
                auto coeff = makeBandPass (lastSampleRate, m.f, m.q);
                for (int ch = 0; ch < modalChannels; ++ch)
                {
                    mm.bp[ch].coefficients = coeff;
                    mm.bp[ch].reset();
                }
                mm.gainLin = juce::Decibels::decibelsToGain (m.gainDb);
            }
            modalDirty = false;
        }

        predelaySamples = juce::jlimit (0, juce::jmax (0, (int) predelayBuf.size() - 2),
                                        (int) std::round (pmPredelayMs * 0.001 * lastSampleRate));
        const int needed = predelaySamples + buffer.getNumSamples() + 2;
        if (needed > (int) predelayBuf.size())
            predelaySamples = juce::jlimit (0, juce::jmax (0, (int) predelayBuf.size() - buffer.getNumSamples() - 2),
                                            predelaySamples);

        modalScratch.clear();

        const float send = juce::jlimit (0.0f, 1.0f, pmBoardSend);
        const float mix  = juce::jlimit (0.0f, 1.0f, pmBoardMix);

        for (int i = 0; i < buffer.getNumSamples(); ++i)
        {
            float mono = 0.0f;
            for (int ch = 0; ch < buffer.getNumChannels(); ++ch)
                mono += buffer.getReadPointer (ch)[i];
            mono *= (buffer.getNumChannels() > 0) ? (1.0f / (float) buffer.getNumChannels()) : 1.0f;
            mono *= send;
            mono = modalSendHpf.processSample (mono);

            predelayBuf[(size_t) predelayWrite] = mono;
            int readIdx = predelayWrite - predelaySamples;
            if (readIdx < 0) readIdx += (int) predelayBuf.size();
            float delayed = predelayBuf[(size_t) readIdx];
            predelayWrite = (predelayWrite + 1) % (int) predelayBuf.size();

            for (size_t m = 0; m < modalModes.size(); ++m)
            {
                for (int ch = 0; ch < buffer.getNumChannels(); ++ch)
                {
                    auto* f = (ch < modalChannels) ? &modalModes[m].bp[ch] : &modalModes[m].bp[0];
                    if (f->coefficients != nullptr)
                    {
                        float w = f->processSample (delayed) * modalModes[m].gainLin;
                        modalScratch.getWritePointer (ch)[i] += w;
                    }
                }
            }
        }

        for (int ch = 0; ch < buffer.getNumChannels(); ++ch)
        {
            auto* dry = buffer.getWritePointer (ch);
            auto* ww  = modalScratch.getWritePointer (ch);
            for (int i = 0; i < buffer.getNumSamples(); ++i)
                dry[i] = dry[i] * (1.0f - mix) + ww[i] * mix;
        }
    }

    // --- Soundboard resonator (procedural IR or JUCE reverb fallback) ---
    if (DebugToggles::kEnableReverb && soundboardEnabled && soundboardMix > 0.0001f)
    {
        soundboardScratch.makeCopyOf (buffer, true);

        {
            juce::dsp::AudioBlock<float> wetBlock (soundboardScratch);
            juce::dsp::ProcessContextReplacing<float> wetCtx (wetBlock);
            soundboardSendHpf.process (wetCtx);
        }

        if (DebugToggles::kEnableSoundboardConvolution)
        {
            updateSoundboardConvolution (false);
            if (DebugToggles::kSoundboardConvolutionDownsample > 1)
            {
                const int dsFactor = DebugToggles::kSoundboardConvolutionDownsample;
                const int numSamples = soundboardScratch.getNumSamples();
                const int numCh = soundboardScratch.getNumChannels();
                const int dsSamples = (numSamples + dsFactor - 1) / dsFactor;

                if (soundboardScratchDs.getNumChannels() != numCh
                    || soundboardScratchDs.getNumSamples() != dsSamples)
                    soundboardScratchDs.setSize (numCh, dsSamples, false, false, true);
                soundboardScratchDs.clear();

                // Downsample by simple averaging to reduce convolution workload.
                for (int ch = 0; ch < numCh; ++ch)
                {
                    const float* src = soundboardScratch.getReadPointer (ch);
                    float* dst = soundboardScratchDs.getWritePointer (ch);
                    int di = 0;
                    for (int i = 0; i < numSamples; i += dsFactor)
                    {
                        float sum = 0.0f;
                        int count = 0;
                        for (int k = 0; k < dsFactor && i + k < numSamples; ++k)
                        {
                            sum += src[i + k];
                            ++count;
                        }
                        dst[di++] = (count > 0) ? (sum / (float) count) : 0.0f;
                    }
                }

                {
                    juce::dsp::AudioBlock<float> wetBlock (soundboardScratchDs);
                    juce::dsp::ProcessContextReplacing<float> wetCtx (wetBlock);
                    soundboardConvolutionDs.process (wetCtx);
                }

                // Upsample with linear interpolation back to full-rate scratch.
                for (int ch = 0; ch < numCh; ++ch)
                {
                    const float* src = soundboardScratchDs.getReadPointer (ch);
                    float* dst = soundboardScratch.getWritePointer (ch);
                    const int dsCount = soundboardScratchDs.getNumSamples();
                    for (int i = 0; i < numSamples; ++i)
                    {
                        const int idx = i / dsFactor;
                        if (idx >= dsCount - 1)
                        {
                            dst[i] = src[dsCount - 1];
                        }
                        else if ((i % dsFactor) == 0)
                        {
                            dst[i] = src[idx];
                        }
                        else
                        {
                            const float frac = (float) (i % dsFactor) / (float) dsFactor;
                            dst[i] = src[idx] + (src[idx + 1] - src[idx]) * frac;
                        }
                    }
                }

                {
                    juce::dsp::AudioBlock<float> wetBlock (soundboardScratch);
                    juce::dsp::ProcessContextReplacing<float> wetCtx (wetBlock);
                    soundboardReturnHpf.process (wetCtx);
                }
            }
            else
            {
                juce::dsp::AudioBlock<float> wetBlock (soundboardScratch);
                juce::dsp::ProcessContextReplacing<float> wetCtx (wetBlock);
                soundboardConvolution.process (wetCtx);
                soundboardReturnHpf.process (wetCtx);
            }
        }
        else
        {
            auto p = soundboardParams;
            p.wetLevel = 1.0f;   // wet only
            p.dryLevel = 0.0f;   // no dry inside
            p.roomSize = juce::jlimit (0.0f, 0.5f, p.roomSize); // Limit room size
            if (! soundboardParamsValid || ! reverbParamsEqual (p, soundboardParamsApplied))
            {
                soundboardReverb.setParameters (p);
                soundboardParamsApplied = p;
                soundboardParamsValid = true;
            }

            if (soundboardScratch.getNumChannels() >= 2)
                soundboardReverb.processStereo (soundboardScratch.getWritePointer (0), soundboardScratch.getWritePointer (1), soundboardScratch.getNumSamples());
            else
                soundboardReverb.processMono (soundboardScratch.getWritePointer (0), soundboardScratch.getNumSamples());
            {
                juce::dsp::AudioBlock<float> wetBlock (soundboardScratch);
                juce::dsp::ProcessContextReplacing<float> wetCtx (wetBlock);
                soundboardReturnHpf.process (wetCtx);
            }
        }

        const float mix = juce::jlimit (0.0f, 1.0f, soundboardMix);
        for (int ch = 0; ch < buffer.getNumChannels(); ++ch)
        {
            auto* dry = buffer.getWritePointer (ch);
            auto* ww  = soundboardScratch.getWritePointer (ch);
            for (int i = 0; i < buffer.getNumSamples(); ++i)
                dry[i] = dry[i] * (1.0f - mix) + ww[i] * mix;
        }
    }

    // --- Mic perspectives blend (post chain) ---
    if (DebugToggles::kEnableMic)
        applyMicMix (buffer);

    // --- Optional post room/hall reverb (testing toggle) ---
    const float postRoomMixParam = apvts.getRawParameterValue (ParamIDs::postRoomMix)->load();
    const bool postRoomEnableParam = apvts.getRawParameterValue (ParamIDs::postRoomEnable)->load() >= 0.5f;
    if (DebugToggles::kEnablePostRoomReverb && postRoomEnableParam && postRoomMixParam > 0.0001f)
    {
        juce::Reverb::Parameters p;
        if (DebugToggles::kPostRoomIsHall)
        {
            p.roomSize = 0.78f;
            p.damping  = 0.45f;
            p.width    = 1.0f;
            p.wetLevel = 0.22f * postRoomMixParam;
            p.dryLevel = 1.0f;
        }
        else
        {
            p.roomSize = 0.42f;
            p.damping  = 0.35f;
            p.width    = 0.9f;
            p.wetLevel = 0.16f * postRoomMixParam;
            p.dryLevel = 1.0f;
        }
        p.freezeMode = 0.0f;
        if (! postReverbParamsValid || ! reverbParamsEqual (p, postReverbParamsApplied))
        {
            postReverb.setParameters (p);
            postReverbParamsApplied = p;
            postReverbParamsValid = true;
        }
        if (buffer.getNumChannels() >= 2)
            postReverb.processStereo (buffer.getWritePointer (0), buffer.getWritePointer (1), buffer.getNumSamples());
        else
            postReverb.processMono (buffer.getWritePointer (0), buffer.getNumSamples());
    }

    // --- Final output HPF to remove sub-bass/rumble ---
    if (DebugToggles::kEnableGlobalFilters)
    {
        if (buffer.getNumChannels() > 0 && buffer.getNumChannels() != outputHpfNumChannels)
        {
            juce::dsp::ProcessSpec spec = mainSpec;
            spec.numChannels = (juce::uint32) juce::jmax (1, buffer.getNumChannels());
            outputHpf.reset();
            outputHpf.prepare (spec);
            auto coeffs = juce::dsp::IIR::Coefficients<float>::makeHighPass (spec.sampleRate,
                                                                             outputHpfCutoff,
                                                                             0.707f);
            if (outputHpf.state == nullptr)
                outputHpf.state = coeffs;
            else
                *outputHpf.state = *coeffs;
            outputHpfNumChannels = buffer.getNumChannels();
        }
        {
            juce::dsp::AudioBlock<float> block (buffer);
            juce::dsp::ProcessContextReplacing<float> ctx (block);
            outputHpf.process (ctx);
        }
    }

    // --- Output padding to ease limiter load ---
    buffer.applyGain (juce::Decibels::decibelsToGain (-3.0f));

    // --- Final lookahead limiter (gain riding + delay) ---
    if (DebugToggles::kEnableFinalLimiter)
    {
        const int numCh = buffer.getNumChannels();
        const int numSamples = buffer.getNumSamples();
        const int requiredSize = limiterLookaheadSamples + numSamples + 1;
        if (numCh != limiterDelayBuffer.getNumChannels() || requiredSize > limiterDelayBufferSize)
        {
            limiterDelayBufferSize = requiredSize;
            limiterDelayBuffer.setSize (juce::jmax (1, numCh), limiterDelayBufferSize, false, false, true);
            limiterDelayBuffer.clear();
            limiterWritePos = 0;
            limiterGain = 1.0f;
        }

        for (int i = 0; i < numSamples; ++i)
        {
            float peak = 0.0f;
            for (int ch = 0; ch < numCh; ++ch)
            {
                const float s = buffer.getReadPointer (ch)[i];
                peak = juce::jmax (peak, std::abs (s));
                limiterDelayBuffer.setSample (ch, limiterWritePos, s);
            }

            const float desiredGain = (peak > limiterThreshold && peak > 0.0f) ? (limiterThreshold / peak) : 1.0f;
            const float coeff = (desiredGain < limiterGain) ? limiterAttackCoeff : limiterReleaseCoeff;
            limiterGain = desiredGain + coeff * (limiterGain - desiredGain);

            int readPos = limiterWritePos - limiterLookaheadSamples;
            if (readPos < 0)
                readPos += limiterDelayBufferSize;
            for (int ch = 0; ch < numCh; ++ch)
            {
                const float delayed = limiterDelayBuffer.getSample (ch, readPos);
                buffer.getWritePointer (ch)[i] = delayed * limiterGain;
            }

            limiterWritePos = (limiterWritePos + 1) % limiterDelayBufferSize;
        }
    }

    // --- Final output LPF (post everything) ---
    if (buffer.getNumChannels() > 0 && buffer.getNumChannels() != outputLpfNumChannels)
    {
        juce::dsp::ProcessSpec spec = mainSpec;
        spec.numChannels = (juce::uint32) juce::jmax (1, buffer.getNumChannels());
        outputLpf.reset();
        outputLpf.prepare (spec);
        outputLpf.setType (juce::dsp::StateVariableTPTFilterType::lowpass);
        outputLpfNumChannels = buffer.getNumChannels();
        updateOutputLpf();
    }

    if (DebugToggles::kEnableGlobalFilters && outputLpfEnabled)
    {
        juce::dsp::AudioBlock<float> block (buffer);
        juce::dsp::ProcessContextReplacing<float> ctx (block);
        outputLpf.process (ctx);
    }

    // --- Output EQ (5-band, post LPF) ---
    if (buffer.getNumChannels() > 0 && buffer.getNumChannels() != outputEqNumChannels)
    {
        juce::dsp::ProcessSpec spec = mainSpec;
        spec.numChannels = (juce::uint32) juce::jmax (1, buffer.getNumChannels());
        for (auto& f : outputEqFilters)
        {
            f.reset();
            f.prepare (spec);
        }
        outputEqNumChannels = buffer.getNumChannels();
        updateOutputEq();
    }

    if (DebugToggles::kEnableEq && outputEqEnabled)
    {
        juce::dsp::AudioBlock<float> block (buffer);
        for (auto& f : outputEqFilters)
        {
            juce::dsp::ProcessContextReplacing<float> ctx (block);
            f.process (ctx);
        }
    }

    // --- Final DC blocker (gentle, post EQ) ---
    if (DebugToggles::kEnableOutputDcBlock)
    {
        if (buffer.getNumChannels() > 0 && buffer.getNumChannels() != outputDcNumChannels)
        {
            const int chs = juce::jmin (2, buffer.getNumChannels());
            for (int ch = 0; ch < chs; ++ch)
                outputDcBlock[(size_t) ch].reset (lastSampleRate);
            outputDcNumChannels = buffer.getNumChannels();
        }
        for (int ch = 0; ch < buffer.getNumChannels(); ++ch)
        {
            auto* x = buffer.getWritePointer (ch);
            auto& dc = outputDcBlock[(size_t) juce::jmin (ch, 1)];
            for (int i = 0; i < buffer.getNumSamples(); ++i)
                x[i] = dc.process (x[i]);
        }
    }

    // --- Master volume (post everything, host-automatable, not preset-controlled) ---
    if (buffer.getNumSamples() > 0 && std::abs (outputGainEnd - outputGainStart) > 1.0e-6f)
        buffer.applyGainRamp (0, buffer.getNumSamples(),
                              masterVolumeLin * outputGainStart,
                              masterVolumeLin * outputGainEnd);
    else
        buffer.applyGain (masterVolumeLin * outputGainLin);
}

//============================== State =========================================
void FluteSynthAudioProcessor::getStateInformation (juce::MemoryBlock& destData)
{
    auto state = apvts.copyState();
    std::unique_ptr<juce::XmlElement> xml (state.createXml());
    copyXmlToBinary (*xml, destData);
}

void FluteSynthAudioProcessor::setStateInformation (const void* data, int sizeInBytes)
{
    std::unique_ptr<juce::XmlElement> xml (getXmlFromBinary (data, sizeInBytes));
    if (xml != nullptr && xml->hasTagName (apvts.state.getType()))
    {
        apvts.replaceState (juce::ValueTree::fromXml (*xml));
        syncExtendedParamsFromAPVTS();
    }
}

//============================= Parameters (VA) =================================
juce::AudioProcessorValueTreeState::ParameterLayout FluteSynthAudioProcessor::createParameterLayout()
{
    std::vector<std::unique_ptr<juce::RangedAudioParameter>> p;

    auto mk = [] (const juce::String& id, const juce::String& name,
                  float min, float max, float def, float centreSkew = 0.0f)
    {
        auto r = juce::NormalisableRange<float> (min, max);
       #if JUCE_VERSION_MAJOR >= 7
        if (centreSkew != 0.0f) r.setSkewForCentre (centreSkew);
       #else
        (void) centreSkew;
       #endif
        return std::make_unique<juce::AudioParameterFloat> (juce::ParameterID (id, 1), name, r, def);
    };
    auto mkBool = [] (const juce::String& id, const juce::String& name, bool def)
    {
        return std::make_unique<juce::AudioParameterBool> (juce::ParameterID (id, 1), name, def);
    };

    // osc mix
    p.push_back (mk (ParamIDs::oscSine,   "Sine",   0.0f, 1.0f, 0.7f));
    p.push_back (mk (ParamIDs::oscSaw,    "Saw",    0.0f, 1.0f, 0.3f));
    p.push_back (mk (ParamIDs::oscSquare, "Square", 0.0f, 1.0f, 0.0f));

    // filter
    p.push_back (mk (ParamIDs::cutoff,    "Cutoff", 100.0f, 8000.0f, 1800.0f, 1000.0f));
    p.push_back (mk (ParamIDs::resonance, "Resonance", 0.1f, 1.5f, 0.7f));

    // ADSR - Note: For pm2 engine, Decay controls physical string sustain time
    p.push_back (mk (ParamIDs::attack,  "Attack",  0.001f, 3.000f, 0.010f));
    p.push_back (mk (ParamIDs::decay,   "Decay (Sustain)",   0.100f, 9.100f, 2.00f, 2.0f));
    p.push_back (mk (ParamIDs::sustain, "Sustain", 0.00f,  1.00f,  0.00f));
    p.push_back (mk (ParamIDs::release, "Release", 0.030f, 7.000f, 1.00f, 1.0f));

    // optional breath/noise pre (voice) gain in dB
    p.push_back (mk (ParamIDs::noiseDb, "Noise (dB)", -62.0f, -12.0f, -48.0f));

    // Formants (post)
    p.push_back (mkBool (ParamIDs::formant1Enable, "Formant 1 Enable", false));
    p.push_back (mk (ParamIDs::formant1Freq,   "Formant 1 Freq",   300.0f, 12000.0f, 1800.0f));
    p.push_back (mk (ParamIDs::formant1Q,      "Formant 1 Q",      0.5f,   6.0f,     2.0f));
    p.push_back (mk (ParamIDs::formant1GainDb, "Formant 1 Gain",  -9.0f,   9.0f,     0.0f));
    p.push_back (mkBool (ParamIDs::formant2Enable, "Formant 2 Enable", false));
    p.push_back (mk (ParamIDs::formant2Freq,   "Formant 2 Freq",   300.0f, 12000.0f, 1800.0f));
    p.push_back (mk (ParamIDs::formant2Q,      "Formant 2 Q",      0.5f,   6.0f,     2.0f));
    p.push_back (mk (ParamIDs::formant2GainDb, "Formant 2 Gain",  -9.0f,   9.0f,     0.0f));

    // Soundboard
    p.push_back (mkBool (ParamIDs::soundboardEnable, "Soundboard Enable", false));
    p.push_back (mk (ParamIDs::soundboardMix,  "Soundboard Mix",  0.0f, 0.20f, 0.02f));
    p.push_back (mk (ParamIDs::soundboardT60,  "Soundboard T60",  1.6f, 2.8f, 2.2f));
    p.push_back (mk (ParamIDs::soundboardDamp, "Soundboard Damping", 0.0f, 1.0f, 0.40f));
    p.push_back (mk (ParamIDs::postRoomMix, "Post Room Mix", 0.0f, 1.0f, 1.0f));
    p.push_back (mkBool (ParamIDs::postRoomEnable, "Post Room Enable", true));

    // Felt/contact
    p.push_back (mk (ParamIDs::feltPreload,    "Felt Preload",    0.0f, 0.6f, 0.08f));
    p.push_back (mk (ParamIDs::feltStiffness,  "Felt Stiffness",  1.0f, 5.0f, 2.4f));
    p.push_back (mk (ParamIDs::feltHysteresis, "Felt Hysteresis", 0.0f, 0.6f, 0.15f));
    p.push_back (mk (ParamIDs::feltMax,        "Felt Max",        0.4f, 4.0f, 1.4f));

    // Duplex
    p.push_back (mk (ParamIDs::duplexRatio,    "Duplex Ratio",    1.1f, 4.0f, 2.2f));
    p.push_back (mk (ParamIDs::duplexGainDb,   "Duplex Gain",   -20.0f, -6.0f, -12.0f));
    p.push_back (mk (ParamIDs::duplexDecayMs,  "Duplex Decay",   10.0f, 400.0f, 120.0f));
    p.push_back (mk (ParamIDs::duplexSympSend, "Sympathetic Send", 0.0f, 1.0f, 0.15f));
    p.push_back (mk (ParamIDs::duplexSympMix,  "Sympathetic Mix",  0.0f, 1.0f, 0.20f));

    // PM2 gain trim - FIXED: Changed default from +12dB to 0dB to prevent overwhelming output
    p.push_back (mk (ParamIDs::pm2GainDb, "PM2 Gain (dB)", -24.0f, 42.0f, 0.0f));

    // Final output LPF
    p.push_back (mkBool (ParamIDs::outputLpfEnable, "Output LPF Enable", false));
    p.push_back (mk (ParamIDs::outputLpfCutoff, "Output LPF Cutoff", 0.0f, 18000.0f, 18000.0f, 4000.0f));
    p.push_back (mk (ParamIDs::outputLpfQ, "Output LPF Q", 0.2f, 2.5f, 0.707f));

    // Master volume (linear gain)
    p.push_back (mk (ParamIDs::masterVolume, "Master Volume", 0.0f, 2.0f, 0.9f, 1.0f));
    p.push_back (std::make_unique<juce::AudioParameterChoice> (
        juce::ParameterID (ParamIDs::temperament, 1),
        "Temperament",
        juce::StringArray { "Preset", "12-TET", "Werckmeister", "Kirnberger", "Meantone", "Pythagorean" },
        0));
    p.push_back (std::make_unique<juce::AudioParameterChoice> (
        juce::ParameterID (ParamIDs::velocityCurve, 1),
        "Velocity Curve",
        juce::StringArray { "Light", "Normal", "Heavy", "Fixed" },
        1));  // Default to "Normal"

    return { p.begin(), p.end() };
}

//=========================== JSON preset helpers ===============================
bool FluteSynthAudioProcessor::hasProp (const juce::DynamicObject& o, const juce::Identifier& id)
{ return o.hasProperty (id); }

float FluteSynthAudioProcessor::getFloatProp (const juce::DynamicObject& o, const juce::Identifier& id, float def)
{
    if (! hasProp (o, id)) return def;
    auto v = o.getProperty (id);
    if (v.isDouble() || v.isInt()) return (float) v;
    return def;
}
bool FluteSynthAudioProcessor::getBoolProp (const juce::DynamicObject& o, const juce::Identifier& id, bool def)
{
    if (! hasProp (o, id)) return def;
    auto v = o.getProperty (id);
    if (v.isBool()) return (bool) v;
    if (v.isInt())  return ((int) v) != 0;
    return def;
}
juce::String FluteSynthAudioProcessor::getStringProp (const juce::DynamicObject& o, const juce::Identifier& id, const juce::String& def)
{
    if (! hasProp (o, id)) return def;
    auto v = o.getProperty (id);
    if (v.isString()) return v.toString();
    return def;
}

static std::array<float,12> getTemperamentOffsetsByName (juce::String name)
{
    name = name.trim().toLowerCase();
    if (name == "pythagorean")
        return { { 0.0f, 23.46f, 3.91f, 27.37f, 7.82f, -13.69f, 11.73f, -1.96f, 21.50f, 1.96f, 25.46f, 5.87f } };
    if (name == "meantone" || name == "quarter-comma meantone" || name == "quarter comma meantone")
        return { { 0.0f, 20.51f, 3.42f, 23.94f, 6.84f, -11.73f, 9.78f, -1.95f, 18.57f, 1.71f, 22.24f, 5.13f } };
    if (name == "werckmeister" || name == "werckmeister iii" || name == "werckmeister3")
        return { { 0.0f, 3.91f, 1.96f, 5.87f, -1.96f, 0.0f, 3.91f, -1.96f, 1.96f, -3.91f, 1.96f, -5.87f } };
    if (name == "kirnberger" || name == "kirnberger iii" || name == "kirnberger3")
        return { { 0.0f, 3.91f, 1.96f, 5.87f, -1.96f, 0.0f, 3.91f, -1.96f, 1.96f, -3.91f, 1.96f, -5.87f } };

    return { { 0.0f } }; // 12-TET default
}

static std::array<float,12> getTemperamentOffsetsByChoice (int choice)
{
    switch (choice)
    {
        case 1:  return getTemperamentOffsetsByName ("12-TET");
        case 2:  return getTemperamentOffsetsByName ("Werckmeister");
        case 3:  return getTemperamentOffsetsByName ("Kirnberger");
        case 4:  return getTemperamentOffsetsByName ("Meantone");
        case 5:  return getTemperamentOffsetsByName ("Pythagorean");
        default: return { { 0.0f } };
    }
}

static std::array<float,128> expandPitchClassOffsets (const std::array<float,12>& offsets)
{
    std::array<float,128> expanded { { 0.0f } };
    for (int i = 0; i < 128; ++i)
        expanded[(size_t) i] = offsets[(size_t) (i % 12)];
    return expanded;
}

PresetModel FluteSynthAudioProcessor::buildPhysicsPresetModel() const
{
    PresetModel p;
    p.engine = "pm2";
    p.engineMixVa = 0.0f;
    p.engineMixPm = 0.0f;
    p.engineMixPm2 = 1.0f;

    const int refMidi = 60;
    p.hammerModel.force = 0.65f;
    p.hammerModel.massKg = PianoPhysics::Hammer::getMass (refMidi);
    p.hammerModel.contactExponent = PianoPhysics::Hammer::getExponent (refMidi);
    p.hammerModel.contactStiffness = mapHammerStiffnessToModel (PianoPhysics::Hammer::getStiffness (refMidi));
    p.hammerModel.contactDamping = juce::jmap (PianoPhysics::Hammer::getHysteresis (refMidi), 0.08f, 0.18f, 4.0f, 8.0f);

    p.feltModel.hysteresis = PianoPhysics::Hammer::getHysteresis (refMidi);

    p.damper.lossDamped = PianoPhysics::Damper::maxDamping;
    p.damper.smoothMs = PianoPhysics::Damper::engageTime_s * 1000.0f;

    p.soundboard.enabled = true;
    p.soundboard.mix = 0.025f;
    const float sbT60 = PianoPhysics::Soundboard::getT60 (200.0f);
    p.soundboard.t60_s = juce::jlimit (1.6f, 2.8f, sbT60);
    p.soundboard.damp = juce::jlimit (0.0f, 1.0f, PianoPhysics::Soundboard::typicalLossFactor / 0.03f);

    // FIX: Reduced PM2 gain and output gain to prevent hot/clipping output
    p.pm2GainDb = -4.0f;      // Was 0.0f - reduce per-voice level
    p.outputGainDb = -9.0f;   // Was -6.0f - additional headroom
    p.breathEnabled = false;
    p.noiseDb = -62.0f;
    p.pedal.sustainGainDb = 3.0f;
    p.damper.lossOff = 1.0f;
    p.damper.lossHalf = 0.80f;    // Was 0.90f - more damping when half-pedal
    p.damper.lossDamped = 0.35f;  // Was 0.65f - VERY aggressive damping for instant note-off
    p.damper.smoothMs = 8.0f;     // Fast damper engage time
    
    // FIX: Very short ADSR release for tight key-tracking
    // Notes should stop almost immediately when you release the key
    p.release = 0.025f;          // Was 0.08f - now 25ms for very tight response
    p.releaseExtension = 1.0f;   // No extension for tighter response
    
    // FIX: Enable output LPF to remove high-frequency crackle/noise/aliasing
    // Cutoff at 12kHz removes harsh artifacts while preserving musicality
    p.outputLpf.enabled = true;
    p.outputLpf.cutoff = 12000.0f;  // Reduced from 14kHz to catch more aliasing
    p.outputLpf.q = 0.707f;  // Butterworth response - smooth rolloff
    
    return p;
}

PresetModel FluteSynthAudioProcessor::parsePresetJson (const juce::var& v)
{
    PresetModel p; // defaults
    if (! v.isObject()) return p;

    auto* obj = v.getDynamicObject();
    auto clamp = PresetModel::clamp;
    const int ver = obj->hasProperty ("schema_version") ? (int) obj->getProperty ("schema_version") : 3;
    juce::ignoreUnused (ver);

    // top-level
    if (hasProp (*obj, "schema_version")) p.schemaVersion = (int) obj->getProperty ("schema_version");
    p.engine  = getStringProp (*obj, "engine", p.engine);
    p.masterTuneCents = clamp (getFloatProp (*obj, "master_tune_cents", p.masterTuneCents), -200.0f, 200.0f);
    p.pitchCompOffsetCents = clamp (getFloatProp (*obj, "pitch_comp_offset_cents", p.pitchCompOffsetCents), -50.0f, 50.0f);
    p.pitchCompSlopeCents = clamp (getFloatProp (*obj, "pitch_comp_slope_cents", p.pitchCompSlopeCents), -0.5f, 0.5f);
    // FIXED: Extended range to allow larger negative slopes for realistic treble attenuation
    p.pm2LoudnessSlopeDbPerSemi = clamp (getFloatProp (*obj, "pm2_loudness_slope_db_per_semi", p.pm2LoudnessSlopeDbPerSemi), -0.10f, 0.1f);
    p.noiseDb = clamp (getFloatProp (*obj, "noise_db", p.noiseDb), -62.0f, -12.0f);
    p.outputGainDb = clamp (getFloatProp (*obj, "output_gain_db", p.outputGainDb), -24.0f, 12.0f);
    p.releaseExtension = clamp (getFloatProp (*obj, "release_extension", p.releaseExtension), 1.0f, 4.0f);
    p.velocityGamma = clamp (getFloatProp (*obj, "velocity_curve_gamma", p.velocityGamma), 0.3f, 3.0f);
    p.velocityCurve = getStringProp (*obj, "velocity_curve", p.velocityCurve);

    if (auto tv = obj->getProperty ("temperament"); tv.isObject())
    {
        if (auto* to = tv.getDynamicObject())
        {
            p.temperamentName = getStringProp (*to, "name", p.temperamentName);
            if (auto ov = to->getProperty ("offsets_cents"); ov.isArray())
            {
                auto* arr = ov.getArray();
                if (arr != nullptr && arr->size() >= 12)
                {
                    for (int i = 0; i < 12; ++i)
                        p.temperamentOffsetsCents[(size_t) i] = (float) arr->getUnchecked (i);
                    p.temperamentUseOffsets = true;
                }
            }
        }
    }

    if (auto ov = obj->getProperty ("per_note_offsets_cents"); ov.isArray())
    {
        auto* arr = ov.getArray();
        if (arr != nullptr && arr->size() > 0)
        {
            if (arr->size() == 12)
            {
                for (int i = 0; i < 128; ++i)
                    p.perNoteOffsetsCents[(size_t) i] = (float) arr->getUnchecked (i % 12);
            }
            else
            {
                for (int i = 0; i < 128; ++i)
                {
                    const int idx = juce::jmin (i, arr->size() - 1);
                    p.perNoteOffsetsCents[(size_t) i] = (float) arr->getUnchecked (idx);
                }
            }
            p.perNoteOffsetsEnabled = true;
        }
    }

    if (auto bv = obj->getProperty ("brightness"); bv.isObject())
    {
        if (auto* bo = bv.getDynamicObject())
        {
            p.brightnessEnabled     = getBoolProp (*bo, "enabled", p.brightnessEnabled);
            p.brightnessBaseDb      = clamp (getFloatProp (*bo, "base_db", p.brightnessBaseDb), -12.0f, 12.0f);
            p.brightnessVelSlopeDb  = clamp (getFloatProp (*bo, "vel_slope_db", p.brightnessVelSlopeDb), -12.0f, 12.0f);
            p.brightnessNoteSlopeDb = clamp (getFloatProp (*bo, "note_slope_db", p.brightnessNoteSlopeDb), -12.0f, 12.0f);
            p.brightnessMaxDb       = clamp (getFloatProp (*bo, "max_db", p.brightnessMaxDb), -12.0f, 18.0f);
            p.brightnessCutoffHz    = clamp (getFloatProp (*bo, "cutoff_hz", p.brightnessCutoffHz), 800.0f, 12000.0f);
            p.brightnessQ           = clamp (getFloatProp (*bo, "q", p.brightnessQ), 0.2f, 4.0f);
        }
    }

    if (auto dv = obj->getProperty ("dispersion_curve"); dv.isObject())
    {
        if (auto* d = dv.getDynamicObject())
        {
            p.dispersion.highMult = clamp (getFloatProp (*d, "high_mult", p.dispersion.highMult), 0.8f, 2.5f);
            p.dispersion.pow      = clamp (getFloatProp (*d, "pow",      p.dispersion.pow),      0.2f, 4.0f);
        }
    }

    // optional engine_mix
    if (auto mv = obj->getProperty ("engine_mix"); mv.isObject())
    {
        if (auto* mm = mv.getDynamicObject())
        {
            p.engineMixVa = clamp (getFloatProp (*mm, "va", p.engineMixVa), 0.0f, 1.0f);
            p.engineMixPm = clamp (getFloatProp (*mm, "pm", p.engineMixPm), 0.0f, 1.0f);
            p.engineMixPm2 = clamp (getFloatProp (*mm, "pm2", p.engineMixPm2), 0.0f, 1.0f);
            float s = juce::jmax (0.0001f, p.engineMixVa + p.engineMixPm + p.engineMixPm2);
            p.engineMixVa  /= s;
            p.engineMixPm  /= s;
            p.engineMixPm2 /= s;
        }
    }
    else
    {
        if (p.engine == "va")      { p.engineMixVa = 1.0f; p.engineMixPm = 0.0f; p.engineMixPm2 = 0.0f; }
        else if (p.engine == "pm") { p.engineMixVa = 0.0f; p.engineMixPm = 1.0f; p.engineMixPm2 = 0.0f; }
        else if (p.engine == "pm2"){ p.engineMixVa = 0.0f; p.engineMixPm = 0.0f; p.engineMixPm2 = 1.0f; }
    else if (p.engine == "hybrid") { p.engineMixVa = 0.5f; p.engineMixPm = 0.5f; p.engineMixPm2 = 0.0f; }
    }

    // osc_mix
    if (auto mv = obj->getProperty ("osc_mix"); mv.isObject())
    {
        if (auto* om = mv.getDynamicObject())
        {
            p.oscSine   = clamp (getFloatProp (*om, "sine",   p.oscSine),   0.0f, 1.0f);
            p.oscSaw    = clamp (getFloatProp (*om, "saw",    p.oscSaw),    0.0f, 1.0f);
            p.oscSquare = clamp (getFloatProp (*om, "square", p.oscSquare), 0.0f, 1.0f);
            auto sum = std::max (0.0001f, p.oscSine + p.oscSaw + p.oscSquare);
            p.oscSine /= sum; p.oscSaw /= sum; p.oscSquare /= sum;
        }
    }

    // filter
    if (auto fv = obj->getProperty ("filter"); fv.isObject())
    {
        if (auto* fo = fv.getDynamicObject())
        {
            p.cutoff = clamp (getFloatProp (*fo, "cutoff", p.cutoff), 100.0f, 8000.0f);
            p.q      = clamp (getFloatProp (*fo, "q",      p.q),      0.1f,   1.5f);
        }
    }

    // env
    if (auto ev = obj->getProperty ("env"); ev.isObject())
    {
        if (auto* eo = ev.getDynamicObject())
        {
            // Use the same ranges as the parameter layout so the embedded preset
            // loads without being truncated.
            p.attack  = clamp (getFloatProp (*eo, "attack",  p.attack),  0.001f, 3.000f);
            p.decay   = clamp (getFloatProp (*eo, "decay",   p.decay),   0.100f, 9.100f);
            p.sustain = clamp (getFloatProp (*eo, "sustain", p.sustain), 0.00f,  1.00f);
            p.release = clamp (getFloatProp (*eo, "release", p.release), 0.030f, 7.000f);
        }
    }

    // shaper
    if (auto sv = obj->getProperty ("shaper"); sv.isObject())
    {
        if (auto* so = sv.getDynamicObject())
        {
            p.shaperEnabled = getBoolProp (*so, "enabled", p.shaperEnabled);
            p.shaperDrive   = clamp (getFloatProp (*so, "drive", p.shaperDrive), 0.0f, 1.0f);
        }
    }

    // breath
    if (auto bv = obj->getProperty ("breath"); bv.isObject())
    {
        if (auto* bo = bv.getDynamicObject())
        {
            p.breathEnabled = getBoolProp (*bo, "enabled", p.breathEnabled);
            p.breathLevelDb = clamp (getFloatProp (*bo, "level_db", p.breathLevelDb), -60.0f, -20.0f);
            p.breathBpFreq  = clamp (getFloatProp (*bo, "bp_freq",  p.breathBpFreq),  1000.0f, 12000.0f);
            p.breathBpQ     = clamp (getFloatProp (*bo, "bp_q",     p.breathBpQ),     0.4f, 3.0f);
        }
    }

    // formants
    if (auto fv2 = obj->getProperty ("formants"); fv2.isArray())
    {
        auto* arr = fv2.getArray();
        for (int i = 0; i < juce::jmin (2, arr->size()); ++i)
        {
            auto el = arr->getUnchecked (i);
            if (! el.isObject()) continue;
            auto* fo = el.getDynamicObject();
            p.formants[i].enabled = getBoolProp (*fo, "enabled", p.formants[i].enabled);
            p.formants[i].freq    = clamp (getFloatProp (*fo, "freq",    p.formants[i].freq),  300.0f, 12000.0f);
            p.formants[i].q       = clamp (getFloatProp (*fo, "q",       p.formants[i].q),     0.5f, 6.0f);
            p.formants[i].gainDb  = clamp (getFloatProp (*fo, "gain_db", p.formants[i].gainDb), -9.0f, +9.0f);
        }
    }

    // hammer
    if (auto hv = obj->getProperty ("hammer"); hv.isObject())
    {
        if (auto* ho = hv.getDynamicObject())
        {
            p.hammer.enabled = getBoolProp (*ho, "enabled", p.hammer.enabled);
            p.hammer.level   = clamp (getFloatProp (*ho, "level",   p.hammer.level),   0.0f, 1.0f);
            p.hammer.decay_s = clamp (getFloatProp (*ho, "decay_s", p.hammer.decay_s), 0.001f, 0.100f);
            p.hammer.noise   = clamp (getFloatProp (*ho, "noise",   p.hammer.noise),   0.0f, 1.0f);
            p.hammer.hp_hz   = clamp (getFloatProp (*ho, "hp_hz",   p.hammer.hp_hz),   200.0f, 12000.0f);
        }
    }

    // action / mechanical noises
    if (auto av = obj->getProperty ("action"); av.isObject())
    {
        if (auto* ao = av.getDynamicObject())
        {
            p.action.keyOffEnabled  = getBoolProp (*ao, "key_off_enabled", p.action.keyOffEnabled);
            p.action.keyOffLevel    = clamp (getFloatProp (*ao, "key_off_level",   p.action.keyOffLevel),   0.0f, 1.0f);
            p.action.keyOffDecay_s  = clamp (getFloatProp (*ao, "key_off_decay_s", p.action.keyOffDecay_s), 0.001f, 0.200f);
            p.action.keyOffVelScale = getBoolProp (*ao, "key_off_vel_scale", p.action.keyOffVelScale);
            p.action.keyOffHp_hz    = clamp (getFloatProp (*ao, "key_off_hp_hz",   p.action.keyOffHp_hz),   200.0f, 12000.0f);

            p.action.pedalEnabled   = getBoolProp (*ao, "pedal_enabled", p.action.pedalEnabled);
            p.action.pedalLevel     = clamp (getFloatProp (*ao, "pedal_level",   p.action.pedalLevel),   0.0f, 1.0f);
            p.action.pedalDecay_s   = clamp (getFloatProp (*ao, "pedal_decay_s", p.action.pedalDecay_s), 0.001f, 0.300f);
            p.action.pedalLp_hz     = clamp (getFloatProp (*ao, "pedal_lp_hz",   p.action.pedalLp_hz),   80.0f, 2000.0f);

            p.action.releaseEnabled = getBoolProp (*ao, "release_enabled", p.action.releaseEnabled);
            p.action.releaseLevel   = clamp (getFloatProp (*ao, "release_level",   p.action.releaseLevel),   0.0f, 1.0f);
            p.action.releaseDecay_s = clamp (getFloatProp (*ao, "release_decay_s", p.action.releaseDecay_s), 0.001f, 0.400f);
            p.action.releaseLp_hz   = clamp (getFloatProp (*ao, "release_lp_hz",   p.action.releaseLp_hz),   80.0f, 2000.0f);
            p.action.releaseThudMix = clamp (getFloatProp (*ao, "release_thud_mix",p.action.releaseThudMix), 0.0f, 1.0f);
            p.action.releaseThudHp_hz = clamp (getFloatProp (*ao, "release_thud_hp_hz", p.action.releaseThudHp_hz), 20.0f, 400.0f);
        }
    }

    // soundboard
    if (auto svb = obj->getProperty ("soundboard"); svb.isObject())
    {
        if (auto* so = svb.getDynamicObject())
        {
            p.soundboard.enabled = getBoolProp (*so, "enabled", p.soundboard.enabled);
            p.soundboard.mix     = clamp (getFloatProp (*so, "mix",   p.soundboard.mix),   0.0f, 1.0f);
            p.soundboard.t60_s   = clamp (getFloatProp (*so, "t60_s", p.soundboard.t60_s), 1.6f, 2.8f);
            p.soundboard.damp    = clamp (getFloatProp (*so, "damp",  p.soundboard.damp),  0.0f, 1.0f);
        }
    }

    // pm_string (pm2 scaffolding)
    if (auto psv = obj->getProperty ("pm_string"); psv.isObject())
    {
        if (auto* ps = psv.getDynamicObject())
        {
            p.pmString.numStrings = juce::jlimit (1, 3, (int) getFloatProp (*ps, "num_strings", (float) p.pmString.numStrings));

            auto clampDetune = [] (float x) { return PresetModel::clamp (x, -5.0f, 5.0f); };
            auto clampGain   = [] (float x) { return PresetModel::clamp (x, 0.0f, 1.0f); };

            if (auto dv = ps->getProperty ("detune_cents"); dv.isArray())
            {
                auto* arr = dv.getArray();
                for (int i = 0; i < juce::jmin ((int) arr->size(), 3); ++i)
                    p.pmString.detuneCents[(size_t) i] = clampDetune ((float) arr->getUnchecked (i));
            }

            if (auto gv = ps->getProperty ("gain"); gv.isArray())
            {
                auto* arr = gv.getArray();
                for (int i = 0; i < juce::jmin ((int) arr->size(), 3); ++i)
                    p.pmString.gain[(size_t) i] = clampGain ((float) arr->getUnchecked (i));
            }

            if (auto pv = ps->getProperty ("pan"); pv.isArray())
            {
                auto* arr = pv.getArray();
                for (int i = 0; i < juce::jmin ((int) arr->size(), 3); ++i)
                    p.pmString.pan[(size_t) i] = PresetModel::clamp ((float) arr->getUnchecked (i), -1.0f, 1.0f);
            }

            p.pmString.stereoWidthLow    = clamp (getFloatProp (*ps, "stereo_width_low",    p.pmString.stereoWidthLow), 0.0f, 1.5f);
            p.pmString.stereoWidthHigh   = clamp (getFloatProp (*ps, "stereo_width_high",   p.pmString.stereoWidthHigh), 0.0f, 1.5f);
            p.pmString.stereoWidthNoteLo = clamp (getFloatProp (*ps, "stereo_width_note_lo", p.pmString.stereoWidthNoteLo), 0.0f, 127.0f);
            p.pmString.stereoWidthNoteHi = clamp (getFloatProp (*ps, "stereo_width_note_hi", p.pmString.stereoWidthNoteHi), 0.0f, 127.0f);

            // normalize gain to sum=1
            float gsum = p.pmString.gain[0] + p.pmString.gain[1] + p.pmString.gain[2];
            if (gsum <= 1e-6f) gsum = 1.0f;
            for (float& g : p.pmString.gain) g = g / gsum;
            for (int i = p.pmString.numStrings; i < 3; ++i)
            {
                p.pmString.detuneCents[(size_t) i] = 0.0f;
                p.pmString.gain[(size_t) i] = 0.0f;
            }

            p.pmString.dispersionAmt = clamp (getFloatProp (*ps, "dispersion_amt", p.pmString.dispersionAmt), 0.0f, 1.0f);
            p.pmString.apStages      = juce::jlimit (1, 4, (int) getFloatProp (*ps, "ap_stages", (float) p.pmString.apStages));
            p.pmString.loss          = clamp (getFloatProp (*ps, "loss", p.pmString.loss), 0.0005f, 0.02f);
            p.pmString.dcBlockHz     = clamp (getFloatProp (*ps, "dc_block_hz", p.pmString.dcBlockHz), 3.0f, 20.0f);
        }
    }

    // hammer_model (pm2 excitation)
    if (auto hv = obj->getProperty ("hammer_model"); hv.isObject())
    {
        if (auto* hm = hv.getDynamicObject())
        {
            p.hammerModel.force    = clamp (getFloatProp (*hm, "force", p.hammerModel.force), 0.0f, 1.0f);
            p.hammerModel.toneHz   = clamp (getFloatProp (*hm, "tone_hz", p.hammerModel.toneHz), 1500.0f, 6000.0f);
            p.hammerModel.attackMs = clamp (getFloatProp (*hm, "attack_ms", p.hammerModel.attackMs), 1.0f, 12.0f);
            p.hammerModel.softclip = getBoolProp (*hm, "softclip", p.hammerModel.softclip);
            p.hammerModel.gamma    = clamp (getFloatProp (*hm, "gamma", p.hammerModel.gamma), 0.6f, 2.5f);
            p.hammerModel.massKg   = clamp (getFloatProp (*hm, "mass_kg", p.hammerModel.massKg), 0.005f, 0.08f);
            p.hammerModel.contactStiffness = clamp (getFloatProp (*hm, "contact_stiffness", p.hammerModel.contactStiffness), 200.0f, 20000.0f);
            p.hammerModel.contactExponent  = clamp (getFloatProp (*hm, "contact_exponent", p.hammerModel.contactExponent), 1.4f, 4.0f);
            p.hammerModel.contactDamping   = clamp (getFloatProp (*hm, "contact_damping", p.hammerModel.contactDamping), 0.5f, 40.0f);
            p.hammerModel.maxPenetration   = clamp (getFloatProp (*hm, "max_penetration", p.hammerModel.maxPenetration), 0.0005f, 0.03f);
            p.hammerModel.attackWindowMs   = clamp (getFloatProp (*hm, "attack_window_ms", p.hammerModel.attackWindowMs), 1.0f, 20.0f);
            p.hammerModel.simplifiedMode   = getBoolProp (*hm, "simplified_mode", p.hammerModel.simplifiedMode);
            p.hammerModel.stiffnessVelScale = clamp (getFloatProp (*hm, "stiffness_vel_scale", p.hammerModel.stiffnessVelScale), 0.0f, 3.0f);
            p.hammerModel.toneVelScale      = clamp (getFloatProp (*hm, "tone_vel_scale", p.hammerModel.toneVelScale), 0.0f, 3.0f);
            p.hammerModel.preloadVelScale   = clamp (getFloatProp (*hm, "preload_vel_scale", p.hammerModel.preloadVelScale), 0.0f, 3.0f);
            p.hammerModel.toneMinHz         = clamp (getFloatProp (*hm, "tone_min_hz", p.hammerModel.toneMinHz), 800.0f, 12000.0f);
            p.hammerModel.toneMaxHz         = clamp (getFloatProp (*hm, "tone_max_hz", p.hammerModel.toneMaxHz), 2000.0f, 18000.0f);
        }
    }

    // felt/contact shaping
    if (auto fv = obj->getProperty ("felt"); fv.isObject())
    {
        if (auto* fo = fv.getDynamicObject())
        {
            p.feltModel.preload    = clamp (getFloatProp (*fo, "felt_preload", p.feltModel.preload),   0.0f, 0.6f);
            p.feltModel.stiffness  = clamp (getFloatProp (*fo, "felt_stiffness", p.feltModel.stiffness), 1.0f, 5.0f);
            p.feltModel.hysteresis = clamp (getFloatProp (*fo, "felt_hysteresis", p.feltModel.hysteresis), 0.0f, 0.6f);
            p.feltModel.maxAmp     = clamp (getFloatProp (*fo, "felt_max", p.feltModel.maxAmp),       0.4f, 4.0f);
        }
    }
    else
    {
        // also accept top-level felt_* keys for convenience
        p.feltModel.preload    = clamp (getFloatProp (*obj, "felt_preload", p.feltModel.preload),   0.0f, 0.6f);
        p.feltModel.stiffness  = clamp (getFloatProp (*obj, "felt_stiffness", p.feltModel.stiffness), 1.0f, 5.0f);
        p.feltModel.hysteresis = clamp (getFloatProp (*obj, "felt_hysteresis", p.feltModel.hysteresis), 0.0f, 0.6f);
        p.feltModel.maxAmp     = clamp (getFloatProp (*obj, "felt_max", p.feltModel.maxAmp),       0.4f, 4.0f);
    }

    // WDF/PH blend
    if (auto wv = obj->getProperty ("wdf"); wv.isObject())
    {
        if (auto* wo = wv.getDynamicObject())
        {
            p.wdf.enabled         = getBoolProp (*wo, "enabled", p.wdf.enabled);
            p.wdf.blend           = clamp (getFloatProp (*wo, "blend", p.wdf.blend), 0.0f, 1.0f);
            p.wdf.loss            = clamp (getFloatProp (*wo, "loss", p.wdf.loss), 0.0f, 0.1f);
            p.wdf.bridgeMass      = clamp (getFloatProp (*wo, "bridge_mass", p.wdf.bridgeMass), 0.1f, 10.0f);
            p.wdf.plateStiffness  = clamp (getFloatProp (*wo, "plate_stiffness", p.wdf.plateStiffness), 0.1f, 5.0f);
        }
    }
    if (auto cv = obj->getProperty ("coupling"); cv.isObject())
    {
        if (auto* co = cv.getDynamicObject())
        {
            p.coupling.gain        = clamp (getFloatProp (*co, "gain",        p.coupling.gain), 0.0f, 0.2f);
            p.coupling.q           = clamp (getFloatProp (*co, "q",           p.coupling.q),    0.2f, 5.0f);
            p.coupling.sympGain    = clamp (getFloatProp (*co, "symp_gain",   p.coupling.sympGain), 0.0f, 0.3f);
            p.coupling.sympHighDamp= clamp (getFloatProp (*co, "symp_high_damp", p.coupling.sympHighDamp), 0.0f, 1.0f);
        }
    }

    // board_modes (modal body)
    if (auto bm = obj->getProperty ("board_modes"); bm.isArray())
    {
        p.boardModes.clear();
        auto* arr = bm.getArray();
        const int maxModes = 16;
        for (int i = 0; i < juce::jmin (maxModes, (int) arr->size()); ++i)
        {
            auto el = arr->getUnchecked (i);
            if (! el.isObject()) continue;
            auto* mo = el.getDynamicObject();
            PresetModel::BoardMode m;
            m.f      = clamp (getFloatProp (*mo, "f", m.f), 60.0f, 5000.0f);
            m.q      = clamp (getFloatProp (*mo, "q", m.q), 0.7f, 8.0f);
            m.gainDb = clamp (getFloatProp (*mo, "gain_db", m.gainDb), -12.0f, 6.0f);
            p.boardModes.add (m);
        }
        if (p.boardModes.isEmpty())
        {
            p.boardModes.add ({ 110.0f, 1.2f, -2.0f });
            p.boardModes.add ({ 250.0f, 1.4f, -1.5f });
            p.boardModes.add ({ 750.0f, 2.0f, -3.0f });
        }
    }
    if (p.boardModes.isEmpty())
    {
        p.boardModes.add ({ 110.0f, 1.2f, -2.0f });
        p.boardModes.add ({ 250.0f, 1.4f, -1.5f });
        p.boardModes.add ({ 750.0f, 2.0f, -3.0f });
    }

    p.boardSend = clamp (getFloatProp (*obj, "board_send", p.boardSend), 0.0f, 1.0f);
    p.boardMix  = clamp (getFloatProp (*obj, "board_mix",  p.boardMix),  0.0f, 1.0f);

    // pm_filter
    if (auto pf = obj->getProperty ("pm_filter"); pf.isObject())
    {
        if (auto* pfo = pf.getDynamicObject())
        {
            p.pmFilter.cutoff   = clamp (getFloatProp (*pfo, "cutoff", p.pmFilter.cutoff),   300.0f, 12000.0f);
            p.pmFilter.q        = clamp (getFloatProp (*pfo, "q",      p.pmFilter.q),        0.01f,  1.2f);
            p.pmFilter.keytrack = clamp (getFloatProp (*pfo, "keytrack", p.pmFilter.keytrack), 0.0f, 1.0f);
        }
    }

    if (auto of = obj->getProperty ("output_lpf"); of.isObject())
    {
        if (auto* oo = of.getDynamicObject())
        {
            p.outputLpf.enabled = getBoolProp (*oo, "enabled", p.outputLpf.enabled);
            p.outputLpf.cutoff  = clamp (getFloatProp (*oo, "cutoff", p.outputLpf.cutoff), 0.0f, 18000.0f);
            p.outputLpf.q       = clamp (getFloatProp (*oo, "q", p.outputLpf.q), 0.2f, 2.5f);
        }
    }

    if (auto prv = obj->getProperty ("post_room"); prv.isObject())
    {
        if (auto* pr = prv.getDynamicObject())
        {
            p.postRoomMix = clamp (getFloatProp (*pr, "mix", p.postRoomMix), 0.0f, 1.0f);
            p.postRoomEnabled = getBoolProp (*pr, "enabled", p.postRoomEnabled);
        }
    }

    if (auto eqv = obj->getProperty ("eq"); eqv.isObject())
    {
        if (auto* eo = eqv.getDynamicObject())
        {
            p.outputEq.enabled = getBoolProp (*eo, "enabled", p.outputEq.enabled);
            if (auto bv = eo->getProperty ("bands"); bv.isArray())
            {
                auto* arr = bv.getArray();
                for (int i = 0; i < juce::jmin (5, (int) arr->size()); ++i)
                {
                    auto el = arr->getUnchecked (i);
                    if (! el.isObject()) continue;
                    auto* bo = el.getDynamicObject();
                    p.outputEq.bands[(size_t) i].freq = clamp (getFloatProp (*bo, "freq", p.outputEq.bands[(size_t) i].freq), 40.0f, 16000.0f);
                    p.outputEq.bands[(size_t) i].q = clamp (getFloatProp (*bo, "q", p.outputEq.bands[(size_t) i].q), 0.3f, 6.0f);
                    p.outputEq.bands[(size_t) i].gainDb = clamp (getFloatProp (*bo, "gain_db", p.outputEq.bands[(size_t) i].gainDb), -18.0f, 18.0f);
                }
            }
        }
    }

    p.tiltDb      = clamp (getFloatProp (*obj, "tilt_db",      p.tiltDb),      -6.0f, 6.0f);
    p.predelayMs  = clamp (getFloatProp (*obj, "predelay_ms",  p.predelayMs),  0.0f, 20.0f);

    // Pedal
    if (auto ped = obj->getProperty ("pedal"); ped.isObject())
    {
        if (auto* po = ped.getDynamicObject())
        {
            p.pedal.sustainThresh    = clamp (getFloatProp (*po, "sustain_thresh",    p.pedal.sustainThresh), 0.0f, 1.0f);
            p.pedal.halfThresh       = clamp (getFloatProp (*po, "half_thresh",       p.pedal.halfThresh),    0.0f, 1.0f);
            p.pedal.halfReleaseScale = clamp (getFloatProp (*po, "half_release_scale", p.pedal.halfReleaseScale), 0.5f, 4.0f);
            p.pedal.repedalMs        = clamp (getFloatProp (*po, "repedal_ms",        p.pedal.repedalMs),     10.0f, 400.0f);
            p.pedal.resonanceSend      = clamp (getFloatProp (*po, "resonance_send",      p.pedal.resonanceSend), 0.0f, 1.0f);
            p.pedal.resonanceMix       = clamp (getFloatProp (*po, "resonance_mix",       p.pedal.resonanceMix),  0.0f, 1.0f);
            p.pedal.resonanceT60       = clamp (getFloatProp (*po, "resonance_t60",       p.pedal.resonanceT60),  0.2f, 4.0f);
            p.pedal.sustainReleaseScale= clamp (getFloatProp (*po, "sustain_release_scale", p.pedal.sustainReleaseScale), 1.0f, 4.0f);
            p.pedal.sustainGainDb      = clamp (getFloatProp (*po, "sustain_gain_db",    p.pedal.sustainGainDb), 0.0f, 6.0f);
        }
    }

    // Damper
    if (auto dv = obj->getProperty ("damper"); dv.isObject())
    {
        if (auto* d = dv.getDynamicObject())
        {
            p.damper.lossDamped = clamp (getFloatProp (*d, "loss_damped", p.damper.lossDamped), 0.5f, 1.0f);
            p.damper.lossHalf   = clamp (getFloatProp (*d, "loss_half",   p.damper.lossHalf),   0.5f, 1.0f);
            p.damper.lossOff    = clamp (getFloatProp (*d, "loss_off",    p.damper.lossOff),    0.8f, 1.2f);
            p.damper.smoothMs   = clamp (getFloatProp (*d, "smooth_ms",   p.damper.smoothMs),   1.0f, 120.0f);
            p.damper.softenMs   = clamp (getFloatProp (*d, "soften_ms",   p.damper.softenMs),   1.0f, 80.0f);
            p.damper.softenHz   = clamp (getFloatProp (*d, "soften_hz",   p.damper.softenHz),   100.0f, 8000.0f);
        }
    }

    if (auto una = obj->getProperty ("una_corda"); una.isObject())
    {
        if (auto* uo = una.getDynamicObject())
        {
            p.unaCorda.detuneCents = clamp (getFloatProp (*uo, "detune_cents", p.unaCorda.detuneCents), -12.0f, 12.0f);
            p.unaCorda.gainScale   = clamp (getFloatProp (*uo, "gain_scale",   p.unaCorda.gainScale),   0.3f, 1.0f);
        }
    }

    if (auto dv = obj->getProperty ("duplex"); dv.isObject())
    {
        if (auto* du = dv.getDynamicObject())
        {
            p.duplex.ratio    = clamp (getFloatProp (*du, "ratio",    p.duplex.ratio),    1.1f, 4.0f);
            p.duplex.gainDb   = clamp (getFloatProp (*du, "gain_db",  p.duplex.gainDb),  -20.0f, -6.0f);
            p.duplex.decayMs  = clamp (getFloatProp (*du, "decay_ms", p.duplex.decayMs),   10.0f, 400.0f);
            p.duplex.sympSend = clamp (getFloatProp (*du, "symp_send", p.duplex.sympSend), 0.0f, 1.0f);
            p.duplex.sympMix  = clamp (getFloatProp (*du, "symp_mix",  p.duplex.sympMix),  0.0f, 1.0f);
            p.duplex.sympNoPedalScale = clamp (getFloatProp (*du, "symp_no_pedal_scale", p.duplex.sympNoPedalScale), 0.0f, 1.0f);
        }
    }

    // Mic perspectives (optional)
    if (auto mv = obj->getProperty ("mics"); mv.isObject())
    {
        if (auto* mo = mv.getDynamicObject())
        {
            auto parseMic = [&clamp] (const juce::DynamicObject* o, PresetModel::Mic& m)
            {
                if (o == nullptr) return;
                m.gainDb      = clamp (getFloatProp (*o, "gain_db",      m.gainDb),     -24.0f, 12.0f);
                m.delayMs     = clamp (getFloatProp (*o, "delay_ms",     m.delayMs),      0.0f, 30.0f);
                m.lowShelfDb  = clamp (getFloatProp (*o, "low_shelf_db", m.lowShelfDb), -12.0f, 12.0f);
                m.highShelfDb = clamp (getFloatProp (*o, "high_shelf_db",m.highShelfDb),-12.0f, 12.0f);
                m.shelfFreq   = clamp (getFloatProp (*o, "shelf_freq",   m.shelfFreq),  200.0f, 8000.0f);
            };

            if (auto c = mo->getProperty ("close"); c.isObject())  parseMic (c.getDynamicObject(),  p.mics.close);
            if (auto c = mo->getProperty ("player"); c.isObject()) parseMic (c.getDynamicObject(), p.mics.player);
            if (auto c = mo->getProperty ("room"); c.isObject())   parseMic (c.getDynamicObject(),   p.mics.room);

            if (auto bv = mo->getProperty ("blend"); bv.isArray())
            {
                auto* arr = bv.getArray();
                for (int i = 0; i < juce::jmin (3, (int) arr->size()); ++i)
                    p.mics.blend[(size_t) i] = clamp ((float) arr->getUnchecked (i), 0.0f, 1.0f);
            }
        }
    }
    {
        float s = p.mics.blend[0] + p.mics.blend[1] + p.mics.blend[2];
        if (s <= 1.0e-6f) { p.mics.blend = { 1.0f, 0.0f, 0.0f }; }
        else { for (float& b : p.mics.blend) b /= s; }
    }

    // Optional loudness trim for pm2 path (defaults to +32 dB, clamps for safety)
    p.pm2GainDb = clamp (getFloatProp (*obj, "pm2_gain_db", p.pm2GainDb), -24.0f, 42.0f);

    return p;
}

void FluteSynthAudioProcessor::applyPresetToParameters (const PresetModel& p)
{
    currentEngine  = p.engine;

    vaMix = juce::jlimit (0.0f, 1.0f, p.engineMixVa);
    pmMix = juce::jlimit (0.0f, 1.0f, p.engineMixPm);
    pm2Mix = juce::jlimit (0.0f, 1.0f, p.engineMixPm2);
    masterTuneCents = p.masterTuneCents;
    pitchCompOffsetCents = p.pitchCompOffsetCents;
    pitchCompSlopeCents = p.pitchCompSlopeCents;
    {
        const auto pcOffsets = p.temperamentUseOffsets ? p.temperamentOffsetsCents
                                                      : getTemperamentOffsetsByName (p.temperamentName);
        presetNoteOffsetsCents = p.perNoteOffsetsEnabled ? p.perNoteOffsetsCents
                                                         : expandPitchClassOffsets (pcOffsets);
        noteOffsetsCents = presetNoteOffsetsCents;
    }
    pm2LoudnessSlopeDbPerSemi = p.pm2LoudnessSlopeDbPerSemi;
    velocityGammaBase = p.velocityGamma;
    velocityGamma = p.velocityGamma;
    velocityCurveName = p.velocityCurve;
    if (velocityCurveName == "soft")       velocityGamma = 0.9f * velocityGamma;
    else if (velocityCurveName == "hard")  velocityGamma = 1.15f * velocityGamma;

    brightnessEnabled      = p.brightnessEnabled;
    brightnessBaseDb       = p.brightnessBaseDb;
    brightnessVelSlopeDb   = p.brightnessVelSlopeDb;
    brightnessNoteSlopeDb  = p.brightnessNoteSlopeDb;
    brightnessMaxDb        = p.brightnessMaxDb;
    brightnessCutoffHz     = p.brightnessCutoffHz;
    brightnessQ            = p.brightnessQ;

    if (lastSampleRate > 0.0)
    {
        const float initialDb = brightnessEnabled ? juce::jlimit (-12.0f, brightnessMaxDb,
                                                                   brightnessBaseDb + lastVelocityNorm * brightnessVelSlopeDb)
                                                  : 0.0f;
        updateBrightnessFilters (initialDb);
        brightnessDbSmoothed.setTargetValue (initialDb);
    }

    dispersionCfg = p.dispersion;
    applyMasterTuneToVoices();

    // APVTS (VA)
    *apvts.getRawParameterValue (ParamIDs::oscSine)   = p.oscSine;
    *apvts.getRawParameterValue (ParamIDs::oscSaw)    = p.oscSaw;
    *apvts.getRawParameterValue (ParamIDs::oscSquare) = p.oscSquare;

    *apvts.getRawParameterValue (ParamIDs::cutoff)    = p.cutoff;
    *apvts.getRawParameterValue (ParamIDs::resonance) = p.q;

    *apvts.getRawParameterValue (ParamIDs::attack)  = p.attack;
    *apvts.getRawParameterValue (ParamIDs::decay)   = p.decay;
    *apvts.getRawParameterValue (ParamIDs::sustain) = p.sustain;
    *apvts.getRawParameterValue (ParamIDs::release) = p.release;
    baseRelease = p.release;
    releaseExtension = p.releaseExtension;

    *apvts.getRawParameterValue (ParamIDs::noiseDb) = p.noiseDb;
    outputGainLin = juce::Decibels::decibelsToGain (p.outputGainDb);
    outputGainLinSmoothed.setTargetValue (outputGainLin);

    // Extended controls (post / pm2 scaffolding)
    *apvts.getRawParameterValue (ParamIDs::formant1Enable) = p.formants[0].enabled ? 1.0f : 0.0f;
    *apvts.getRawParameterValue (ParamIDs::formant1Freq)   = p.formants[0].freq;
    *apvts.getRawParameterValue (ParamIDs::formant1Q)      = p.formants[0].q;
    *apvts.getRawParameterValue (ParamIDs::formant1GainDb) = p.formants[0].gainDb;
    *apvts.getRawParameterValue (ParamIDs::formant2Enable) = p.formants[1].enabled ? 1.0f : 0.0f;
    *apvts.getRawParameterValue (ParamIDs::formant2Freq)   = p.formants[1].freq;
    *apvts.getRawParameterValue (ParamIDs::formant2Q)      = p.formants[1].q;
    *apvts.getRawParameterValue (ParamIDs::formant2GainDb) = p.formants[1].gainDb;

    *apvts.getRawParameterValue (ParamIDs::soundboardEnable) = p.soundboard.enabled ? 1.0f : 0.0f;
    *apvts.getRawParameterValue (ParamIDs::soundboardMix)    = p.soundboard.mix;
    *apvts.getRawParameterValue (ParamIDs::soundboardT60)    = p.soundboard.t60_s;
    *apvts.getRawParameterValue (ParamIDs::soundboardDamp)   = p.soundboard.damp;
    *apvts.getRawParameterValue (ParamIDs::postRoomMix)      = p.postRoomMix;
    *apvts.getRawParameterValue (ParamIDs::postRoomEnable)   = p.postRoomEnabled ? 1.0f : 0.0f;

    *apvts.getRawParameterValue (ParamIDs::feltPreload)    = p.feltModel.preload;
    *apvts.getRawParameterValue (ParamIDs::feltStiffness)  = p.feltModel.stiffness;
    *apvts.getRawParameterValue (ParamIDs::feltHysteresis) = p.feltModel.hysteresis;
    *apvts.getRawParameterValue (ParamIDs::feltMax)        = p.feltModel.maxAmp;

    *apvts.getRawParameterValue (ParamIDs::duplexRatio)    = p.duplex.ratio;
    *apvts.getRawParameterValue (ParamIDs::duplexGainDb)   = p.duplex.gainDb;
    *apvts.getRawParameterValue (ParamIDs::duplexDecayMs)  = p.duplex.decayMs;
    *apvts.getRawParameterValue (ParamIDs::duplexSympSend) = p.duplex.sympSend;
    *apvts.getRawParameterValue (ParamIDs::duplexSympMix)  = p.duplex.sympMix;

    *apvts.getRawParameterValue (ParamIDs::pm2GainDb) = p.pm2GainDb;
    *apvts.getRawParameterValue (ParamIDs::outputLpfEnable) = p.outputLpf.enabled ? 1.0f : 0.0f;
    *apvts.getRawParameterValue (ParamIDs::outputLpfCutoff) = p.outputLpf.cutoff;
    *apvts.getRawParameterValue (ParamIDs::outputLpfQ)      = p.outputLpf.q;
    if (auto* v = apvts.getRawParameterValue (ParamIDs::temperament))
        *v = 0.0f; // "Preset"

    // Shaper
    shaperEnabled = p.shaperEnabled;
    shaperDrive   = p.shaperDrive;

    // Breath
    breathEnabled = p.breathEnabled;
    breathGainLin = juce::Decibels::decibelsToGain (p.breathLevelDb);
    breathBpFreqStored = p.breathBpFreq;
    breathBpQStored    = p.breathBpQ;
    breathBp.setCutoffFrequency (breathBpFreqStored);
    breathBp.setResonance       (breathBpQStored);

    // Formants
    for (int i = 0; i < 2; ++i)
    {
        formant[i].enabled = p.formants[i].enabled;
        formant[i].f.setCutoffFrequency (p.formants[i].freq);
        formant[i].f.setResonance       (p.formants[i].q);
        formant[i].gainLin = juce::Decibels::decibelsToGain (p.formants[i].gainDb);
    }

    // Hammer
    hammerEnabled = p.hammer.enabled;
    hammerLevel   = p.hammer.level;
    hammerNoise   = p.hammer.noise;
    hammerActive  = false;
    hammerEnv     = 0.0f;
    hammerHpHz    = p.hammer.hp_hz;
    hammerDecaySec = p.hammer.decay_s;  // Store for recalculation in prepareToPlay
    // Calculate decay coefficient (will be recalculated in prepareToPlay if sample rate was 0)
    if (hammerDecaySec <= 0.0005f) hammerDecayCoeff = 0.0f;
    else if (lastSampleRate > 0.0)
    {
        const double tau = std::max (0.0005, (double) hammerDecaySec);
        hammerDecayCoeff = (float) std::exp (-1.0 / (tau * lastSampleRate));
    }
    // else: leave hammerDecayCoeff at default, will be fixed in prepareToPlay
    hammerHP.setCutoffFrequency (hammerHpHz);

    // Action / mechanical noises
    keyOffEnabled    = p.action.keyOffEnabled;
    keyOffVelScale   = p.action.keyOffVelScale;
    keyOffLevel      = p.action.keyOffLevel;
    keyOffEnv        = 0.0f;
    keyOffDecaySec   = p.action.keyOffDecay_s;
    keyOffHpHz       = p.action.keyOffHp_hz;
    if (keyOffDecaySec <= 0.0005f) keyOffDecayCoeff = 0.0f;
    else if (lastSampleRate > 0.0)
    {
        const double tau = std::max (0.0005, (double) keyOffDecaySec);
        keyOffDecayCoeff = (float) std::exp (-1.0 / (tau * lastSampleRate));
    }
    keyOffHP.setCutoffFrequency (keyOffHpHz);

    pedalThumpEnabled   = p.action.pedalEnabled;
    pedalThumpLevel     = p.action.pedalLevel;
    pedalThumpEnv       = 0.0f;
    pedalThumpDecaySec  = p.action.pedalDecay_s;
    pedalThumpLpHz      = p.action.pedalLp_hz;
    if (pedalThumpDecaySec <= 0.0005f) pedalThumpDecayCoeff = 0.0f;
    else if (lastSampleRate > 0.0)
    {
        const double tau = std::max (0.0005, (double) pedalThumpDecaySec);
        pedalThumpDecayCoeff = (float) std::exp (-1.0 / (tau * lastSampleRate));
    }
    pedalThumpLP.setCutoffFrequency (pedalThumpLpHz);

    releaseThumpEnabled   = p.action.releaseEnabled;
    releaseThumpLevel     = p.action.releaseLevel;
    releaseThumpEnv       = 0.0f;
    releaseThumpDecaySec  = p.action.releaseDecay_s;
    releaseThumpLpHz      = p.action.releaseLp_hz;
    releaseThudMix        = p.action.releaseThudMix;
    releaseThudHpHz       = p.action.releaseThudHp_hz;
    if (releaseThumpDecaySec <= 0.0005f) releaseThumpDecayCoeff = 0.0f;
    else if (lastSampleRate > 0.0)
    {
        const double tau = std::max (0.0005, (double) releaseThumpDecaySec);
        releaseThumpDecayCoeff = (float) std::exp (-1.0 / (tau * lastSampleRate));
    }
    releaseThumpLP.setCutoffFrequency (releaseThumpLpHz);
    releaseThudHP.setCutoffFrequency (releaseThudHpHz);
    damperCfg = p.damper;
    updateDamperCoeffs();

    // Soundboard
    soundboardEnabled = p.soundboard.enabled;
    soundboardMix     = p.soundboard.mix;

    soundboardParams = {};
    const float room = juce::jlimit (0.0f, 1.0f, p.soundboard.t60_s / 3.0f); // 0..~3s
    soundboardParams.roomSize = room;
    soundboardParams.damping  = juce::jlimit (0.0f, 1.0f, p.soundboard.damp);
    soundboardParams.width    = 0.6f;
    soundboardParams.wetLevel = 1.0f; // we do wet/dry outside
    soundboardParams.dryLevel = 0.0f;

    // NEW: pass the same ADSR to the PM engine so env.* applies there too
    for (int i = 0; i < synth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<FluteVoice*> (synth.getVoice (i)))
        {
            v->setPitchComp (pitchCompOffsetCents, pitchCompSlopeCents);
            v->setNoteOffsets (noteOffsetsCents);
        }
    for (int i = 0; i < pmSynth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<PmVoice*> (pmSynth.getVoice (i)))
        {
            v->setEnvParams (p.attack, p.decay, p.sustain, p.release);
            v->setReleaseScale (baseRelease, 1.0f);
            v->setPitchComp (pitchCompOffsetCents, pitchCompSlopeCents);
            v->setNoteOffsets (noteOffsetsCents);
        }
    for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
        {
            v->setEnvParams (p.attack, p.decay, p.sustain, p.release);
            v->setReleaseScale (baseRelease, 1.0f);
            v->setWdfParams (sanitizeWdf (p.wdf));
            v->setPitchComp (pitchCompOffsetCents, pitchCompSlopeCents);
            v->setNoteOffsets (noteOffsetsCents);
            v->setLoudnessSlope (pm2LoudnessSlopeDbPerSemi);
            v->setReleaseExtension (p.releaseExtension);
            v->setSustainPedalDown (sustainPedalDown);
            v->setDamperParams (p.damper);
            v->setDamperLift (damperLift);
            v->setCouplingParams (p.coupling);
        }

    // pm2 scaffolding (store parsed values; DSP lands in Phase 2)
    pmString = p.pmString;
    pmHammer = p.hammerModel;
    pmFelt = p.feltModel;
    wdfCfg = sanitizeWdf (p.wdf);
    couplingCfg = p.coupling;
    pmBoardModes = p.boardModes;
    pmBoardSend = p.boardSend;
    pmBoardMix  = p.boardMix;
    pmToneFilter = p.pmFilter;
    pmTiltDb = p.tiltDb;
    pmPredelayMs = p.predelayMs;
    pedalCfg = p.pedal;
    damperCfg = p.damper;
    unaCfg = p.unaCorda;
    duplexCfg = p.duplex;
    micCfg = p.mics;
    halfReleaseScale = p.pedal.halfReleaseScale;
    pm2GainDb = p.pm2GainDb;
    pm2GainLin = juce::Decibels::decibelsToGain (pm2GainDb);
    postCutoffHz = p.pmFilter.cutoff;
    postQ = p.pmFilter.q;
    postKeytrack = p.pmFilter.keytrack;
    postTiltDb = p.tiltDb;
    outputLpfEnabled = p.outputLpf.enabled && DebugToggles::kEnableOutputLpf;
    outputLpfCutoff  = p.outputLpf.cutoff;
    outputLpfQ       = p.outputLpf.q;
    postCutoffHzSmoothed.setTargetValue (postCutoffHz);
    postQSmoothed.setTargetValue (postQ);
    postTiltDbSmoothed.setTargetValue (postTiltDb);
    outputLpfCutoffSmoothed.setTargetValue (outputLpfCutoff);
    outputLpfQSmoothed.setTargetValue (outputLpfQ);
    outputEqEnabled  = p.outputEq.enabled;
    outputEqCfg      = p.outputEq;
    if (! prepared || ! anyVoiceActive())
    {
        postVaLp1.reset();  postVaLp2.reset();
        postPmLp1.reset();  postPmLp2.reset();
        postPm2Lp1.reset(); postPm2Lp2.reset();
        tiltLow.reset(); tiltHigh.reset();
        outputLpf.reset();
        for (auto& f : outputEqFilters)
            f.reset();
    }
    else
    {
        pendingStateReset = true;
    }
    for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
        {
            v->setParams (p.pmString);
            v->setHammerParams (p.hammerModel);
            v->setFeltParams (p.feltModel);
            v->setDuplexParams (p.duplex);
            v->setSoftPedal (softPedalDown, p.unaCorda);
            v->setEnvParams (p.attack, p.decay, p.sustain, p.release);
        }
    modalDirty = true;
    // Pedal resonance
    if (! prepared || ! anyVoiceActive())
        pedalReverb.reset();
    pedalReverbParams = {};
    pedalReverbParams.roomSize = juce::jlimit (0.0f, 1.0f, p.pedal.resonanceT60 / 3.0f);
    pedalReverbParams.damping  = 0.4f;
    pedalReverbParams.wetLevel = 1.0f;
    pedalReverbParams.dryLevel = 0.0f;

    // Sympathetic reverb params (light, short)
    if (! prepared || ! anyVoiceActive())
        sympReverb.reset();
    sympParams = {};
    sympParams.roomSize = juce::jlimit (0.0f, 1.0f, p.duplex.decayMs / 400.0f); // rough tie to decay
    sympParams.damping  = 0.4f;
    sympParams.wetLevel = 1.0f;
    sympParams.dryLevel = 0.0f;

    // Ensure runtime state matches APVTS (so host automation works)
    syncExtendedParamsFromAPVTS();

    updatePostFiltersForNote (lastMidiNote);
    updateOutputLpf();
    updateOutputEq();
    tiltReady = (tiltLow.coefficients != nullptr && tiltHigh.coefficients != nullptr);
    updateMicProcessors();
    presetUiSyncPending.store (true, std::memory_order_release);
}

// Public API used by CLI or GUI reset
bool FluteSynthAudioProcessor::loadEmbeddedPreset ()
{
    if (! loadEmbeddedPresetModel())
        return false;

    if (embeddedPresets.empty())
        return false;

    const int presetIdx = juce::jlimit (0, (int) embeddedPresets.size() - 1,
                                        activeEmbeddedPresetIndex.load());

    // If not yet prepared (constructor/startup), apply immediately.
    if (! prepared)
    {
        activeEmbeddedPresetIndex.store (presetIdx, std::memory_order_release);
        applyPresetToParameters (embeddedPresets[(size_t) presetIdx].model);
        return true;
    }

    // Otherwise, schedule application on the audio thread to avoid GUI/DSP races.
    requestEmbeddedPresetApply (presetIdx);
    return true;
}

bool FluteSynthAudioProcessor::loadEmbeddedPresetModel ()
{
    // FIX: Always load presets from JSON file, but apply physics-based parameters
    // This ensures all presets appear in the dropdown menu
    
    if (BinaryData::preset_jsonSize <= 0)
    {
        // Fallback: create single physics preset if no JSON available
        if (PhysicsToggles::kUsePhysicsDefaults)
        {
            embeddedPresetLoaded.store (false, std::memory_order_release);
            embeddedPresets.clear();
            EmbeddedPreset ep;
            ep.name = "Physics Default";
            ep.model = buildPhysicsPresetModel();
            embeddedPresets.push_back (std::move (ep));
            embeddedPresetLoaded.store (true, std::memory_order_release);
            activeEmbeddedPresetIndex.store (0, std::memory_order_release);
            return true;
        }
        return false;
    }

    embeddedPresetLoaded.store (false, std::memory_order_release);
    embeddedPresets.clear();

    juce::MemoryInputStream in (BinaryData::preset_json,
                                (size_t) BinaryData::preset_jsonSize,
                                false);
    auto text = in.readEntireStreamAsString();

    if (text.startsWith ("```"))
    {
        text = text.fromFirstOccurrenceOf ("```", false, false);
        text = text.fromFirstOccurrenceOf ("\n", false, false);
        text = text.upToLastOccurrenceOf ("```", false, false);
    }
    text = text.replace ("\\_", "_");

    juce::var v = juce::JSON::parse (text);
    if (v.isVoid())
        return false;

    embeddedPresets.clear();

    auto pushPreset = [this] (const juce::var& presetVar, int idx)
    {
        juce::String name = "Preset " + juce::String (idx + 1);
        if (auto* obj = presetVar.getDynamicObject())
            if (obj->hasProperty ("name") && obj->getProperty ("name").isString())
                name = obj->getProperty ("name").toString();

        EmbeddedPreset ep;
        ep.name = name;
        // Parse preset from JSON - the JSON now contains physics-compatible values
        ep.model = parsePresetJson (presetVar);
        embeddedPresets.push_back (std::move (ep));
    };

    if (auto* obj = v.getDynamicObject())
    {
        if (auto presetsVar = obj->getProperty ("presets"); presetsVar.isArray())
        {
            auto* arr = presetsVar.getArray();
            for (int i = 0; i < arr->size(); ++i)
                pushPreset (arr->getReference (i), i);
        }
        else
        {
            pushPreset (v, 0);
        }
    }
    else if (v.isArray())
    {
        auto* arr = v.getArray();
        for (int i = 0; i < arr->size(); ++i)
            pushPreset (arr->getReference (i), i);
    }

    if (embeddedPresets.empty())
        return false;

    embeddedPresetLoaded.store (true, std::memory_order_release);
    activeEmbeddedPresetIndex.store (juce::jlimit (0, (int) embeddedPresets.size() - 1,
                                                   activeEmbeddedPresetIndex.load()),
                                     std::memory_order_release);
    return true;
}

void FluteSynthAudioProcessor::resetToEmbeddedPreset()
{
    requestEmbeddedPresetApply (activeEmbeddedPresetIndex.load());
}

bool FluteSynthAudioProcessor::loadPresetFromJson (const juce::File& file)
{
    if (PhysicsToggles::kUsePhysicsDefaults)
    {
        applyPresetToParameters (buildPhysicsPresetModel());
        return true;
    }

    if (! file.existsAsFile()) return false;

    juce::var v;
    {
        juce::FileInputStream in (file);
        if (! in.openedOk()) return false;
        auto text = in.readEntireStreamAsString();

        // tolerate common chat artifacts
        if (text.startsWith ("```"))
        {
            text = text.fromFirstOccurrenceOf ("```", false, false);
            text = text.fromFirstOccurrenceOf ("\n", false, false);
            text = text.upToLastOccurrenceOf ("```", false, false);
        }
        text = text.replace ("\\_", "_");

        v = juce::JSON::parse (text);
        if (v.isVoid()) return false;
    }

    auto model = parsePresetJson (v);
    applyPresetToParameters (model);

    return true;
}

void FluteSynthAudioProcessor::setWdfForTest (const PresetModel::WdfModel& wdfModel)
{
    wdfCfg = sanitizeWdf (wdfModel);
    for (int i = 0; i < pm2Synth.getNumVoices(); ++i)
        if (auto* v = dynamic_cast<Pm2Voice*> (pm2Synth.getVoice (i)))
            v->setWdfParams (wdfCfg);
}

void FluteSynthAudioProcessor::requestEmbeddedPresetApply()
{
    requestEmbeddedPresetApply (activeEmbeddedPresetIndex.load());
}

void FluteSynthAudioProcessor::requestEmbeddedPresetApply (int index)
{
    if (! embeddedPresetLoaded.load())
        loadEmbeddedPresetModel();

    if (embeddedPresets.empty())
        return;

    const int clamped = juce::jlimit (0, (int) embeddedPresets.size() - 1, index);
    activeEmbeddedPresetIndex.store (clamped, std::memory_order_release);

    if (! prepared)
    {
        applyPresetToParameters (embeddedPresets[(size_t) clamped].model);
        return;
    }

    pendingEmbeddedPresetIndex.store (clamped, std::memory_order_release);
}

juce::StringArray FluteSynthAudioProcessor::getEmbeddedPresetNames() const
{
    if (! embeddedPresetLoaded.load())
        const_cast<FluteSynthAudioProcessor*> (this)->loadEmbeddedPresetModel();

    juce::StringArray names;
    for (const auto& p : embeddedPresets)
        names.add (p.name);
    return names;
}

int FluteSynthAudioProcessor::getActiveEmbeddedPresetIndex() const
{
    return activeEmbeddedPresetIndex.load();
}

void FluteSynthAudioProcessor::selectEmbeddedPreset (int index)
{
    requestEmbeddedPresetApply (index);
}

bool FluteSynthAudioProcessor::consumePendingPresetUiSync()
{
    return presetUiSyncPending.exchange (false, std::memory_order_acq_rel);
}

// Factory function for JUCE wrappers
juce::AudioProcessor* JUCE_CALLTYPE createPluginFilter()
{
    return new FluteSynthAudioProcessor();
}