JS Wobble/Bassline Synth w/ Random Speed/Playback!!

<center>
<button>Start Wobble</button>
<script>
var context = new AudioContext();
var frequency;
document.querySelector("button").addEventListener("click", GenRandomWobble);
function GenRandomWobble() {
frequency = Math.floor(Math.random() * 100)+50;
var Osc1 = context.createOscillator();
var Osc2 = context.createOscillator();
Osc1.type = "saw";
Osc1.frequency.value = frequency;
Osc1.connect(context.destination);
Osc2.type = "saw";
Osc2.frequency.value = frequency;
Osc2.detune.value = -90;
Osc2.connect(context.destination);
var Timer =Math.floor(Math.random()*60);
Osc1.start(context.currentTime);
Osc1.stop(context.currentTime + Timer);
Osc2.start(context.currentTime + 0);
Osc2.stop(context.currentTime + Timer);
alert('Frequency: '+frequency+ "\n\nSeconds Total: "+Timer);
}
</script>
</center>