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DynamicsCompressorNode.release

The release property of the DynamicsCompressorNode interface Is a k-rate AudioParam representing the amount of time, in seconds, required to increase the gain by 10 dB. It defines how quick the signal is adapted when its volume is reduced.

The release property's default value is 0.25 and it can be set between 0 and 1.

Syntax

var audioCtx = new AudioContext();
var compressor = audioCtx.createDynamicsCompressor();
compressor.release.value = 0.25;

Value

An AudioParam.

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

Example

The below code demonstrates a simple usage of createDynamicsCompressor() to add compression to an audio track. For a more complete example, have a look at our basic Compressor example (view the source code).

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

// Create a compressor node
var compressor = audioCtx.createDynamicsCompressor();
compressor.threshold.value = -50;
compressor.knee.value = 40;
compressor.ratio.value = 12;
compressor.attack.value = 0;
compressor.release.value = 0.25;

// connect the AudioBufferSourceNode to the destination
source.connect(audioCtx.destination);

button.onclick = function() {
  var active = button.getAttribute('data-active');
  if(active == 'false') {
    button.setAttribute('data-active', 'true');
    button.innerHTML = 'Remove compression';

    source.disconnect(audioCtx.destination);
    source.connect(compressor);
    compressor.connect(audioCtx.destination);
  } else if(active == 'true') {
    button.setAttribute('data-active', 'false');
    button.innerHTML = 'Add compression';

    source.disconnect(compressor);
    compressor.disconnect(audioCtx.destination);
    source.connect(audioCtx.destination);
  }
}

Specifications

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

Browser compatibility

Feature Chrome Edge Firefox Internet Explorer Opera Safari
Basic support 14 Yes 25 No 15 6
Feature Android webview Chrome for Android Edge mobile Firefox for Android IE mobile Opera Android iOS Safari
Basic support Yes 14 Yes 26 No 15 ?

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/DynamicsCompressorNode/release