crossbrowdy/CrossBrowdy/CrossBase/audiovisual/audio/jsfx/synth.html

A Multimedia JavaScript framework to create real cross-platform and hybrid game engines, games, emulators, multimedia libraries and apps.

<b>Note this is broken on Chrome ATM.</b>
<p>Play with <b>AWSEDFTGYHUJK</b> keys.</p>
<script src="jsfx.js"></script>
<script>

var modules = [
	jsfx.Module.Frequency,
	jsfx.Module.Vibrato,
	jsfx.Module.Guitar,
	jsfx.Module.Volume
];

var base = function(){
	return {
		Frequency: { Slide: (Math.random() - 0.5)/5 },
		Vibrato: {
			Depth: Math.random() / 10,
			Frequency: Math.random() * 10 + 5
		},
		Volume: { Master: 1, Attack: 0, Punch: 1, Release: 1, Decay: 3 }
	};
};

var live = jsfx.Live({}, modules);
var scale = "AWSEDFTGYHUJK";

document.onkeydown = function(ev){
	var key = String.fromCharCode(ev.which);
	var note = scale.indexOf(key);
	var freq = 440 * Math.pow(2, note/12);

	var params = MergeParams(base, { "Frequency": {"Start": freq}});
	live._play(params);
};

// modifies the override
function MergeParams(base, override){
	if(typeof base === 'function'){
		base = base();
	} else {
		base = JSON.parse(JSON.stringify(base));
	}

	if(typeof override === 'function'){
		override = override();
	}

	for(var name in override){
		if(typeof base[name] === 'undefined'){
			base[name] = {};
		}
		for(var param in override[name]){
			base[name][param] = override[name][param];
		}
	}

	return base;
}

</script>