DelayNode.delayTime - Web APIs 编辑

The delayTime property of the DelayNode interface is an a-rate AudioParam representing the amount of delay to apply.

delayTime is expressed in seconds, its minimal value is 0, and its maximum value is defined by the maxDelayTime argument of the AudioContext.createDelay() method that created it.

Syntax

var audioCtx = new AudioContext();
var myDelay = audioCtx.createDelay(5.0);
myDelay.delayTime.value = 3.0;

Note: Though the AudioParam returned is read-only, the value it represents is not.

Value

An AudioParam.

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