DelayNode

The DelayNode interface represents a delay-line; an AudioNode audio-processing module that causes a delay between the arrival of an input data and its propagation to the output. A DelayNode always has exactly one input and one output, both with the same amount of channels.

The DelayNode acts as a delay-line, here with a value of 1s.

When creating a graph that has a cycle, it is mandatory to have at least one DelayNode in the cycle, or the nodes taking part in the cycle will be muted.

Number of inputs 1
Number of outputs 1
Channel count mode "max"
Channel count 2 (not used in the default count mode)
Channel interpretation "speakers"

Properties

Inherits properties from its parent, AudioNode.

DelayNode.delayTime Read only
Is an a-rate AudioParam representing the amount of delay to apply.

Methods

No specific methods; inherits methods from its parent, AudioNode.

Example

We have created a simple example that allows you to play three different samples on a constant loop — see create-delay (you can also view the source code). If you just press the play buttons, the loops will start immediately; if you slide the sliders up to the right, then press the play buttons, a delay will be introduced, so the looping sounds don't start playing for a short amount of time.

js;highlight[4,15,16,21,22]
var AudioContext = window.AudioContext || window.webkitAudioContext;
var audioCtx = new AudioContext();

var synthDelay = audioCtx.createDelay(5.0);

  ...

var synthSource;

playSynth.onclick = function() {
  synthSource = audioCtx.createBufferSource();
  synthSource.buffer = buffers[2];
  synthSource.loop = true;
  synthSource.start();
  synthSource.connect(synthDelay);
  synthDelay.connect(destination);
  this.setAttribute('disabled', 'disabled');
}

stopSynth.onclick = function() {
  synthSource.disconnect(synthDelay);
  synthDelay.disconnect(destination);
  synthSource.stop();
  playSynth.removeAttribute('disabled');
}

...

var delay1;
rangeSynth.oninput = function() {
delay1 = rangeSynth.value;
synthDelay.delayTime.value = delay1;
}

Specifications

Specification Status Comment
Web Audio API
The definition of 'DelayNode' in that specification.
Working Draft  

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 10.0webkit 25.0 (25.0)  Not supported 15.0webkit
22 (unprefixed)
6.0webkit
Feature Android Firefox Mobile (Gecko) Firefox OS IE Mobile Opera Mobile Safari Mobile Chrome for Android
Basic support ? 26.0 1.2 ? ? ? 33.0

See also

License

© 2016 Mozilla Contributors
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-us/docs/web/api/delaynode

API Audio DelayNode Interface Reference Web Audio API