function createConvolver(path, callback, errorCallback) {
  if (window.location.origin.indexOf('file://') > -1 && window.cordova === 'undefined') {
    alert('This sketch may require a server to load external files. Please see http://bit.ly/1qcInwS');
  }
  var self = this;
  var cReverb = new reverb_Convolver(path, function (buffer) {
    if (typeof callback === 'function') {
      callback(buffer);
    }
    if (typeof self._decrementPreload === 'function') {
      self._decrementPreload();
    }
  }, errorCallback);
  cReverb.impulses = [];
  return cReverb;
}
Create a p5.Convolver. Accepts a path to a soundfile
 that will be used to generate an impulse response.

 @method  createConvolver
 @for p5
 @param  {String}   path     path to a sound file
 @param  {Function} [callback] function to call if loading is successful.
                               The object will be passed in as the argument
                               to the callback function.
 @param  {Function} [errorCallback] function to call if loading is not successful.
                               A custom error will be passed in as the argument
                               to the callback function.
 @return {p5.Convolver}
 @example
 <div><code>
 let cVerb, sound;
 function preload() {
   // We have both MP3 and OGG versions of all sound assets
   soundFormats('ogg', 'mp3');

   // Try replacing 'bx-spring' with other soundfiles like
   // 'concrete-tunnel' 'small-plate' 'drum' 'beatbox'
   cVerb = createConvolver('assets/bx-spring.mp3');

   // Try replacing 'Damscray_DancingTiger' with
   // 'beat', 'doorbell', lucky_dragons_-_power_melody'
   sound = loadSound('assets/Damscray_DancingTiger.mp3');
 }

 function setup() {
   let cnv = createCanvas(100, 100);
   cnv.mousePressed(playSound);
   background(220);
   text('tap to play', 20, 20);

   // disconnect from main output...
   sound.disconnect();

   // ...and process with cVerb
   // so that we only hear the convolution
   cVerb.process(sound);
 }

 function playSound() {
   sound.play();
 }
 </code></div>