cutoff, resonance, decay, and env mod working

plugins/Nekobi/DistrhoPluginNekobi.cpp

@@ -95,7 +95,7 @@ DistrhoPluginNekobi::DistrhoPluginNekobi()
     // Default values
     fParams.waveform = 0.0f;
     fParams.tuning = 0.0f;
-    fParams.cutoff = 25.0f;
+    fParams.cutoff = 63.0f;
     fParams.resonance = 25.0f;
     fParams.envMod = 50.0f;
     fParams.decay  = 75.0f;
@@ -105,10 +105,10 @@ DistrhoPluginNekobi::DistrhoPluginNekobi()
     // Internal stuff
     fSynth.waveform  = 0.0f;
     fSynth.tuning    = 1.0f;
-    fSynth.cutoff    = 5.0f;
+    fSynth.cutoff    = 63.0f;
     fSynth.resonance = 0.8f;
-    fSynth.envmod    = 0.3f;
+    fSynth.envmod    = 50.0f;
-    fSynth.decay     = 0.0002f;
+    fSynth.decay     = 75.0f;
     fSynth.accent    = 0.3f;
     fSynth.volume    = 0.75f;
 
@@ -180,7 +180,7 @@ void DistrhoPluginNekobi::initParameter(uint32_t index, Parameter& parameter)
         parameter.unit       = "%";
         parameter.ranges.def = 25.0f;
         parameter.ranges.min = 0.0f;
-        parameter.ranges.max = 95.0f;
+        parameter.ranges.max = 100.0f;
         parameter.midiCC = 71;
         break;
     case paramEnvMod:
@@ -190,7 +190,7 @@ void DistrhoPluginNekobi::initParameter(uint32_t index, Parameter& parameter)
         parameter.unit       = "%";
         parameter.ranges.def = 50.0f;
         parameter.ranges.min = 0.0f;
-        parameter.ranges.max = 100.0f;
+        parameter.ranges.max = 127.0f;
         parameter.midiCC = 1; //Mod Wheel
         break;
     case paramDecay:
@@ -200,7 +200,7 @@ void DistrhoPluginNekobi::initParameter(uint32_t index, Parameter& parameter)
         parameter.unit       = "%";
         parameter.ranges.def = 75.0f;
         parameter.ranges.min = 0.0f;
-        parameter.ranges.max = 100.0f;
+        parameter.ranges.max = 127.0f;
         parameter.midiCC = 72;
         break;
     case paramAccent:
@@ -280,13 +280,13 @@ void DistrhoPluginNekobi::setParameterValue(uint32_t index, float value)
         break;
     case paramEnvMod:
         fParams.envMod = value;
-        fSynth.envmod = value/100.0f;
+        fSynth.envmod = value;
-        DISTRHO_SAFE_ASSERT(fSynth.envmod >= 0.0f && fSynth.envmod <= 1.0f);
+        DISTRHO_SAFE_ASSERT(fSynth.envmod >= 0.0f && fSynth.envmod <= 127.0f);
         break;
     case paramDecay:
         fParams.decay = value;
-        fSynth.decay = value/100.0f * 0.000491f + 0.000009f; // FIXME: log?
+        fSynth.decay = value;
-        DISTRHO_SAFE_ASSERT(fSynth.decay >= 0.000009f && fSynth.decay <= 0.0005f);
+        DISTRHO_SAFE_ASSERT(fSynth.decay >= 0.0f && fSynth.decay <= 127.0f);
         break;
     case paramAccent:
         fParams.accent = value;

plugins/Nekobi/DistrhoUINekobi.cpp

@@ -83,7 +83,7 @@ DistrhoUINekobi::DistrhoUINekobi()
     fKnobEnvMod = new ImageKnob(this, knobImage, ImageKnob::Vertical);
     fKnobEnvMod->setId(DistrhoPluginNekobi::paramEnvMod);
     fKnobEnvMod->setAbsolutePos(329, 43);
-    fKnobEnvMod->setRange(0.0f, 100.0f);
+    fKnobEnvMod->setRange(0.0f, 127.0f);
     fKnobEnvMod->setDefault(50.0f);
     fKnobEnvMod->setValue(50.0f);
     fKnobEnvMod->setRotationAngle(305);
@@ -93,7 +93,7 @@ DistrhoUINekobi::DistrhoUINekobi()
     fKnobDecay = new ImageKnob(this, knobImage, ImageKnob::Vertical);
     fKnobDecay->setId(DistrhoPluginNekobi::paramDecay);
     fKnobDecay->setAbsolutePos(400, 43);
-    fKnobDecay->setRange(0.0f, 100.0f);
+    fKnobDecay->setRange(0.0f, 127.0f);
     fKnobDecay->setDefault(75.0f);
     fKnobDecay->setValue(75.0f);
     fKnobDecay->setRotationAngle(305);

plugins/Nekobi/nekobee-src/nekobee_synth.c

@@ -189,6 +189,8 @@ void nekobee_synth_render_voices(nekobee_synth_t *synth, float *out,
     wow = res * res;
     wow = wow / 10.0f;
 
+
+    // FIXME just... fix this
     // as the resonance is increased, "wow" slows down the accent attack
     if ((synth->voice->velocity > 90) &&
         (synth->vcf_accent < synth->voice->vcf_eg)) {
@@ -205,10 +207,9 @@ void nekobee_synth_render_voices(nekobee_synth_t *synth, float *out,
         synth->vca_accent =
             0.95 * synth->vca_accent;  // accent off with time constant
     }
-#if defined(XSYNTH_DEBUG) && (XSYNTH_DEBUG & XDB_AUDIO)
+
-    out[0] += 0.10f; /* add a 'buzz' to output so there's something audible even
+    //out[0] += 0.10f; /* add a 'buzz' to output so there's something audible even
-                        when quiescent */
+
-#endif               /* defined(XSYNTH_DEBUG) && (XSYNTH_DEBUG & XDB_AUDIO) */
     if (_PLAYING(synth->voice)) {
         nekobee_voice_render(synth, out, sample_count);
     }

plugins/Nekobi/nekobee-src/nekobee_voice.c

@@ -58,6 +58,7 @@ nekobee_voice_note_on(nekobee_synth_t *synth, nekobee_voice_t *voice,
     int i;
     voice->key      = key;
     voice->velocity = velocity;
+    voice->vcf_eg = 9.8f;
 
 
    if (!synth->monophonic || !(_ON(voice) || _SUSTAINED(voice))) {
@@ -74,14 +75,14 @@ nekobee_voice_note_on(nekobee_synth_t *synth, nekobee_voice_t *voice,
             }
         
         if (!_PLAYING(voice)) {
+            //printf("resetting voice\n");
             voice->lfo_pos = 0.0f;
             voice->vca_eg = 0.0f;
-            voice->vcf_eg = 0.0f;
+            voice->vcf_eg = 9.8f;
             voice->delay1 = 0.0f;
             voice->delay2 = 0.0f;
             voice->delay3 = 0.0f;
             voice->delay4 = 0.0f;
-            voice->c5     = 0.0f;
             voice->osc_index = 0;
             voice->osc.phase = 0.0f;
 			
@@ -127,9 +128,10 @@ nekobee_voice_note_on(nekobee_synth_t *synth, nekobee_voice_t *voice,
     }
     synth->held_keys[0] = key;
 
+    // FIXME check if this mess is necessary
     if (!_PLAYING(voice)) {
-
+        voice->status = XSYNTH_VOICE_ON;
-        nekobee_voice_start_voice(voice);
+        //nekobee_voice_start_voice(voice);
 
     } else if (!_ON(voice)) {  /* must be XSYNTH_VOICE_SUSTAINED or XSYNTH_VOICE_RELEASED */
 

plugins/Nekobi/nekobee-src/nekobee_voice.h

@@ -76,12 +76,13 @@ struct _nekobee_voice_t {
     /* persistent voice state */
     float prev_pitch, target_pitch, lfo_pos;
     struct blosc_t osc;
-    float vca_eg, vcf_eg, accent_slug, delay1, delay2, delay3, delay4, c5;
+    float vca_eg, vcf_eg, accent_slug, delay1, delay2, delay3, delay4;
+    float vca_tc, vcf_tc;   // VCA and VCF time constants
     unsigned char vca_eg_phase, vcf_eg_phase;
     int osc_index; /* shared index into osc_audio */
     float osc_audio[XSYNTH_NUGGET_SIZE];
-    float freqcut_buf[XSYNTH_NUGGET_SIZE];
+    float delayhp;
-    float vca_buf[XSYNTH_NUGGET_SIZE];
+    
 };
 
 #define _PLAYING(voice) ((voice)->status != XSYNTH_VOICE_OFF)
@@ -124,12 +125,4 @@ static inline void nekobee_voice_off(nekobee_voice_t *voice) {
     /* -FIX- decrement active voice count? */
 }
 
-/*
- * nekobee_voice_start_voice
- */
-static inline void nekobee_voice_start_voice(nekobee_voice_t *voice) {
-    voice->status = XSYNTH_VOICE_ON;
-    /* -FIX- increment active voice count? */
-}
-
 #endif /* _XSYNTH_VOICE_H */

plugins/Nekobi/nekobee-src/nekobee_voice_render.c

@@ -118,6 +118,9 @@ void vcf(nekobee_synth_t *synth, float *out, uint32_t count) {
     float delay1 = voice->delay1, delay2 = voice->delay2,
           delay3 = voice->delay3, delay4 = voice->delay4;
 
+    float vcf_eg = voice->vcf_eg;
+    float delayhp = voice->delayhp;
+
     // to get the correct cutoff first we need Q10's collector current
     // The top of VR3 Cutoff is fed from 12V, the bottom from the emitter
     // of Q9 at around 3.2V through a 10k resistor. So, 8.8V between "rails"
@@ -131,7 +134,20 @@ void vcf(nekobee_synth_t *synth, float *out, uint32_t count) {
 
     float Vcutoff = 1.47 + 7.41 * logpot[(int)floor(synth->cutoff)];
 
-    float Vbe1 = -5.077;  // mV
+    // similarly the envelope modulation pot is 50k log in series with 10k
+    // but the top of the pot is fed with the envelope voltage, about 10V at
+    // peak
+
+    float Renvmod = .167 + .833 * logpot[(int)floor(synth->envmod)];
+
+    // subtract the 3.2V offset from Q9
+    float Venvmod = (voice->vcf_eg - 3.2) * Renvmod;
+
+    // R63 and R71 form a voltage divider, 2.2k / (220k + 2.2k) = 0.0099
+    // multiply by 1000 to get a voltage in mV
+
+    Venvmod *= 9.901;
+    float Vbe1 = Venvmod;
 
     // .3 is 300k expressed as MOhm
     // if we expressed it in Ohms output would be in A
@@ -148,29 +164,48 @@ void vcf(nekobee_synth_t *synth, float *out, uint32_t count) {
     ct = ct / (1 + ct);
     // printf("cutoff = %04fHz, ct=%f\n", cutoff, ct);
 
+    float hpc = 6.28 * 16 * synth->deltat;
+    float fout, hp;
+
     for (uint32_t i = 0; i < count; i++) {
         for (uint32_t ovs = 0; ovs < 4; ovs++) {
             float in = voice->osc_audio[i];
-            float fb = in - (delay4 * synth->resonance * 4);
+            float fb = tanh(in - ((fout - 0.25*in) * synth->resonance * 6));
-            if (fb > 3) fb = 3;
+
-            if (fb < -3) fb = -3;
             delay1 = ((fb - delay1) * ct) + delay1;
             delay2 = ((delay1 - delay2) * ct) + delay2;
             delay3 = ((delay2 - delay3) * ct) + delay3;
             delay4 = ((delay3 - delay4) * ct) + delay4;
+            hp = ((delay4 - delayhp) * hpc ) + delayhp;
+            delayhp = hp;
+            fout = delay4-hp;
         }
-        out[i] = delay4;
+        out[i] = fout;
+        vcf_eg *= 1 - voice->vcf_tc;
     }
-
     voice->delay1 = delay1;
     voice->delay2 = delay2;
     voice->delay3 = delay3;
     voice->delay4 = delay4;
+
+    voice->vcf_eg = vcf_eg;
+    voice->delayhp = delayhp;
 }
 
 void nekobee_voice_render(nekobee_synth_t *synth, float *out, uint32_t count) {
     // generate "count" samples into the buffer at out
 
+    // FIXME factor this out into the control code
+    // Decay is about 2.5 seconds with the pot all the way down, and 200ms with
+    // it all the way up this is set by a 1M log pot in series with a 68k
+    // resistor, a 1uF capacitor, and a bunch of other stuff to give a correct
+    // DC offset and a log tailoff right at the very bottom
+
+    synth->voice->vcf_tc =
+        (1 / ((68 + 1000 * logpot[(int)synth->decay]) * 0.001)) * synth->deltat;
+    // printf("tc = %f deltat=%f pot=%f\n",synth->voice->vcf_tc,
+    // synth->deltat,logpot[(int)synth->decay]);
+
     vco(synth, count);
 
     vcf(synth, out, count);