Changes speed of a sound file up to 3 times forward or backward

sound samplerate tweaker.pde

/*
Changes speed of a sound file up to 3 times forward or backward
use with an analog input.
Remember to add youw own sound file
Reconfigure to use whatever analog input you like
Steve Lambert November 24, 2015
*/

// Variables
float knobPos = 500;


// Sound stuff
import processing.sound.*;

SoundFile hitit;


void setup() {
  size(200, 200);
  background(255);
    
  // Load a soundfile from the data folder of the sketch and play it back in a loop

// CHANGE THE NAME OF THIS SOUND FILE TO SOMETHING YOU PUT IN THE DATA FOLDER //
  hitit = new SoundFile(this, "hitit.wav"); 
}      

void draw() {
  knobPos = constrain(knobPos, 0, 1000);
}

void keyPressed() {
  if (key == '1'){
    hitit.play();
    hitit.amp(1.5);
  } //end if 1
  

  
} // end keyPressed

void mouseWheel(MouseEvent event) {
  float e = event.getCount();
    float speed = map(knobPos,0,1000,-3,3);
  knobPos = knobPos - e;
  //println("knobPos: " + knobPos + " e: " + e);
  println("speed: " + speed);
  hitit.rate(speed);
}