Web audio api, stop sound gracefully

Question

The web audio api furnish the method .stop() to stop a sound. I want my sound to decrease in volume before stopping. To do so I used a gain node. However I\'m f

Answer 1

Aaah, yes, yes, yes! I finally found a lot of things by eventually bothering to read "everything" in the doc (diagonally). And let me tell you this api is a diamond in the rough. Anyway, they actually have what I wanted with Audio param :

The AudioParam interface represents an audio-related parameter, usually a parameter of an AudioNode (such as GainNode.gain). An AudioParam can be set to a specific value or a change in value, and can be scheduled to happen at a specific time and following a specific pattern.

It has a function linearRampToValueAtTime()

And they even have an example with what I asked !

// create audio context
var AudioContext = window.AudioContext || window.webkitAudioContext;
var audioCtx = new AudioContext();

// set basic variables for example
var myAudio = document.querySelector('audio');
var pre = document.querySelector('pre');
var myScript = document.querySelector('script');

pre.innerHTML = myScript.innerHTML;

var linearRampPlus = document.querySelector('.linear-ramp-plus');
var linearRampMinus = document.querySelector('.linear-ramp-minus');

// Create a MediaElementAudioSourceNode
// Feed the HTMLMediaElement into it
var source = audioCtx.createMediaElementSource(myAudio);

// Create a gain node and set it's gain value to 0.5
var gainNode = audioCtx.createGain();

// connect the AudioBufferSourceNode to the gainNode
// and the gainNode to the destination
gainNode.gain.setValueAtTime(0, audioCtx.currentTime);
source.connect(gainNode);
gainNode.connect(audioCtx.destination);

// set buttons to do something onclick
linearRampPlus.onclick = function() {
  gainNode.gain.linearRampToValueAtTime(1.0, audioCtx.currentTime + 2);
}

linearRampMinus.onclick = function() {
  gainNode.gain.linearRampToValueAtTime(0, audioCtx.currentTime + 2);
}

Working example here

They also have different type of timings, like exponential instead of linear ramp which I guess would fit this scenario more.