ConvolverNode.buffer

The buffer property of the ConvolverNode interface represents a mono, stereo, or 4-channel AudioBuffer containing the (possibly multichannel) impulse response used by the ConvolverNode to create the reverb effect.

This is normally a simple recording of as-close-to-an-impulse as can be found in the space you want to model. For example, if you want to model the reverb in your bathroom, you might set up a microphone near the door to record the sound of a balloon pop or synthesized impulse from the sink. That audio recording could then be used as the buffer.

This AudioBuffer must have the same sample-rate as the AudioContext or an exception will be thrown. At the time when this attribute is set, the buffer and the state of the attribute will be used to configure the ConvolverNode with this impulse response having the given normalization. The initial value of this attribute is null.

Syntax

var audioCtx = new AudioContext();
var convolver = audioCtx.createConvolver();
convolver.buffer = myAudioBuffer;

Value

An AudioBuffer.

Example

var audioCtx = new (window.AudioContext || window.webkitAudioContext)();
var convolver = audioCtx.createConvolver();

  ...

// grab audio track via XHR for convolver node

var soundSource, concertHallBuffer;

ajaxRequest = new XMLHttpRequest();
ajaxRequest.open('GET', 'concert-crowd.ogg', true);
ajaxRequest.responseType = 'arraybuffer';

ajaxRequest.onload = function() {
  var audioData = ajaxRequest.response;
  audioCtx.decodeAudioData(audioData, function(buffer) {
      concertHallBuffer = buffer;
      soundSource = audioCtx.createBufferSource();
      soundSource.buffer = concertHallBuffer;
    }, function(e){"Error with decoding audio data" + e.err});
}

ajaxRequest.send();

  ...

convolver.buffer = concertHallBuffer;

Specifications

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

Browser compatibility

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`buffer`	Chrome Full support 14	Edge Full support 12	Firefox Full support 25	IE No support No	Opera Full support 15	Safari Full support 6	WebView Android Full support Yes	Chrome Android Full support 18	Firefox Android Full support 26	Opera Android Full support 14	Safari iOS Full support Yes	Samsung Internet Android Full support 1.0

Legend

Full support: Full support
No support: No support