code: function SoundLoader(loadItem, preferXHR) {
  		this.AbstractMediaLoader_constructor(loadItem, preferXHR, createjs.AbstractLoader.SOUND);
  
  		// protected properties
  		if (createjs.DomUtils.isAudioTag(loadItem)) {
  			this._tag = loadItem;
  		} else if (createjs.DomUtils.isAudioTag(loadItem.src)) {
  			this._tag = loadItem;
  		} else if (createjs.DomUtils.isAudioTag(loadItem.tag)) {
  			this._tag = createjs.DomUtils.isAudioTag(loadItem) ? loadItem : loadItem.src;
  		}
  
  		if (this._tag != null) {
  			this._preferXHR = false;
  		}
  	}
docs: constructor 
  A loader for HTML audio files. PreloadJS can not load WebAudio files, as a WebAudio context is required, which
  should be created by either a library playing the sound (such as <a href="http://soundjs.com">SoundJS</a>, or an
  external framework that handles audio playback. To load content that can be played by WebAudio, use the
  {{#crossLink "BinaryLoader"}}{{/crossLink}}, and handle the audio context decoding manually.
  @class SoundLoader
  @param {LoadItem|Object} loadItem
  @param {Boolean} preferXHR
  @extends AbstractMediaLoader
  @constructor