MuscleSynth is a synthesizer which you control via your muscles.

musclesynth.ino

// Dependencies: eHealth, Mozzi.

#include <eHealth.h>
float ECG = 0;
int ECGfreq = 100;
unsigned long lastsampleECG = 0;
unsigned long time = 0;

#include <MozziGuts.h>
#include <ReverbTank.h>
#include <Oscil.h>
#include <tables/cos8192_int8.h>
#include <tables/envelop2048_uint8.h>
#include <tables/cos512_int8.h> // for filter modulation
#include <Sample.h> // Sample template
#include <samples/TJBAnalogDisk/Acid_mozzi/FMAcidBass4_int8.h> // Bass sample

#include <LowPassFilter.h>
#include <mozzi_rand.h> // for rand()

#define CONTROL_RATE 64 // quite fast, keeps modulation smooth

// Sample
Sample <FMACIDBASS4_NUM_CELLS, AUDIO_RATE> aSample(FMACIDBASS4_DATA);

// Reverb
ReverbTank reverb;

// OSCs
Oscil <COS8192_NUM_CELLS, AUDIO_RATE> aCarrier(COS8192_DATA);
Oscil <COS8192_NUM_CELLS, AUDIO_RATE> aModulator(COS8192_DATA);
Oscil <COS8192_NUM_CELLS, AUDIO_RATE> aModWidth(COS8192_DATA);
Oscil <COS8192_NUM_CELLS, CONTROL_RATE> kModFreq1(COS8192_DATA);
Oscil <COS8192_NUM_CELLS, CONTROL_RATE> kModFreq2(COS8192_DATA);
Oscil <ENVELOP2048_NUM_CELLS, AUDIO_RATE> aEnvelop(ENVELOP2048_DATA);
Oscil <COS512_NUM_CELLS, CONTROL_RATE> kFilterMod1(COS512_DATA);
Oscil <COS512_NUM_CELLS, CONTROL_RATE> kFilterMod2(COS512_DATA); 

LowPassFilter lpf1;
LowPassFilter lpf2;

void setup(){
  // synth, mods, lpf and sample  params
  aCarrier.setFreq(40);
  kModFreq1.setFreq(3.98f);
  kModFreq2.setFreq(3.31757f);
  aModWidth.setFreq(2.52434f);
  aEnvelop.setFreq(9.0f);
  kFilterMod1.setFreq(1.3f);
  kFilterMod2.setFreq(0.1f);
  lpf1.setResonance(180);
  lpf2.setResonance(220);
  aSample.setFreq((float) FMACIDBASS4_SAMPLERATE / (float) FMACIDBASS4_NUM_CELLS);

  startMozzi();
}


void updateControl(){
  
  ECG = eHealth.getECG();

  byte cutoff_freq1 = 50; // desired 150 ± 63, input 4-1
  byte cutoff_freq2 = 20; // desired 70 ± 31 , input 4-1
  
  if (ECG < 2.5){
    byte cutoff_freq1 = 300; // desired 150 ± 63, input 4-1
    byte cutoff_freq2 = 100; // desired 70 ± 31 , input 4-1
  }
  if (ECG > 2.5){
    aSample.start();
  }
  lpf1.setCutoffFreq(cutoff_freq1);
  lpf2.setCutoffFreq(cutoff_freq2);  
  
  aModulator.setFreq(260.0f + 0.4313f*kModFreq1.next() + kModFreq2.next());
}


int updateAudio(){
  int synth = aCarrier.phMod((int)aModulator.next()*(100u+aModWidth.next()));
  synth *= (unsigned char)aEnvelop.next();
  synth >>= 8;
  // here's the reverb
  int arev = reverb.next(synth);
  // add the dry and wet signals
  return (char)lpf1.next(synth) + (char)lpf2.next((arev>>3)) + (int) aSample.next();
}


void loop(){
  audioHook();
}