function loaded(){
			loadCount--;
			if (loadCount === 0){
				if (this.isFunction(url)){
					url();
				}
			}
		}
Add a buffer to the list of buffers, or load the given url
@param {String|Object} name The name of the buffer. Or pass in an object
                            with the name as the keys and urls as the values
@param {String|Tone.Buffer} url  Either the url to load, or the
                                 Tone.Buffer which corresponds to the name.
@param {Function=} callback The callback to invoke when the buffer is loaded.
@returns {Tone.MultiPlayer} this