Binaural Beat Generation, Creating an Illusory Sound with Processing

gistfile1.txt

//this code will generate two different frequencies in each ear
//which is then experienced as a third frequency that exists due to
//the brain listening to both

//need to be wearing headphones for this to work correctly
import processing.sound.*;
SinOsc[] sines;
float f = 7.0;//freqeuncy of illusory sound


void setup() {
  size(640, 360);
  background(255);
  sines = new SinOsc[2];
  for(int i = 0 ; i < sines.length ; i++){
    sines[i] = new SinOsc(this);
    sines[i].freq(100+i*f);
    if(i%2==0) sines[i].pan(-1.0);
    else sines[i].pan(1.0);
    sines[i].amp(0.4);
    sines[i].play();
  }
}    

float downtime = 60*1000*5.0; //transition time from start freq to end freq

//the draw function will start at a higher illusory frequency and then
//make its way down to the ending frequency over the course of some time
//denoted by downtime
void draw() {
  int m = millis();
  float freq = 2.5; //ending frequency
  if(m  for(int i = 0 ; i < sines.length ; i++){
    sines[i].freq(100+i*freq);
  }
  println(freq);
}