load-sound.js

var loadSound = function(url, context, callback, err) {

	var decodeSuccess = function(buffer) {
		callback(buffer);
	};

	var decodeError = function(request) {
		return function(response) {
			try {
				throw 'Error decoding sound at `' + url + '`. This is as good as the error gets. Sorry.';
			} catch (message) {
				if (typeof err === 'function') {
					err(message, request);
				}
			}
		};
	}

	var decodeAudioData = function(e) {
		var request = e.currentTarget;
		context.decodeAudioData(request.response, decodeSuccess, decodeError(request));
	}

	var load = function(url) {
		var request = new XMLHttpRequest();

		request.open('GET', url);
		request.responseType = 'arraybuffer';
		request.onload = decodeAudioData;
		request.send();

		return request;
	};

	var request = load(url);

	return request;
};