JSFiddle - React, Tailwind, and code Playground

JavaScript

var context = new webkitAudioContext();

var sound = context.createOscillator();
sound.frequency.value = 440;

var sidechain = context.createOscillator();
sidechain.frequency.value = 1;

var gain = context.createGainNode();
gain.gain.value = 0;

sound.connect(gain);
gain.connect(context.destination);
sidechain.connect(gain.gain);

sound.noteOn(0);
sidechain.noteOn(0);

setTimeout(function () {
    sound.noteOff(0);
    sidechain.noteOff(0);
}, 3000);