JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://tonejs.github.io/Logo/build/Waveform.js"></script>
<link rel="stylesheet" href="https://tonejs.github.io/assets/css/interface.css">
<script src="https://tonejs.github.io/build/Tone.min.js"></script>

JavaScript

var delay = new Tone.FeedbackDelay(0.2, 0.5).toMaster()
delay.delayTime.value = 0.25

var oscillator = new Tone.LFO(0.6, 0.1, 0.5).connect(delay.delayTime).start()
oscillator.type = 'sawtooth'


var url = "https://tonejs.github.io/examples/audio/casio/A1.mp3"
var player = new Tone.Player(url).connect(delay)
player.loop = true


Tone.Buffer.on('load', function(){
 var now = Tone.now()
	player.start(now)
	/* delay.delayTime.rampTo(0.5, 2) */
})