Web Audio Base (basic initialization)

webAudioStart.js

// basic minimum initialization

window.AudioContext = window.AudioContext || window.webkitAudioContext;
var audioContext = new AudioContext();

// set latency hint
if ("latencyHint" in audioContext) {
audioContext.latencyHint = "playback";
};

var baseFreq = 440; // A4, Midi Note #69
var baseTempo = 120; // BPM
var audioOut = audioContext.destination;