BaseAudioContext.createDelay() - Web APIs 编辑

The createDelay() method of the BaseAudioContext Interface is used to create a DelayNode, which is used to delay the incoming audio signal by a certain amount of time.

Syntax

var delayNode = audioCtx.createDelay(maxDelayTime);

Parameters

maxDelayTime Optional

The maximum amount of time, in seconds, that the audio signal can be delayed by. Must be less than 180 seconds, and defaults to 1 second if not specified.

Returns

A DelayNode. The default DelayNode.delayTime is 0 seconds.

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.

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.setValueAtTime(delay1, audioCtx.currentTime);
}

Specifications

Browser compatibility

BCD tables only load in the browser

See also

• Using the Web Audio API