The buffer property of the AudioBufferSourceNode interface provides the ability to play back audio using an AudioBuffer as the source of the sound data.

If the buffer property is set to the value null, the node generates a single channel containing silence (that is, every sample is 0).


AudioBufferSourceNode.buffer = soundBuffer;


An AudioBuffer which contains the data representing the sound which the node will play.


For a full working example, see this code running live, or view the source.

var myArrayBuffer = audioCtx.createBuffer(2, frameCount, audioCtx.sampleRate);

button.onclick = function() {
  // Fill the buffer with white noise;
  //just random values between -1.0 and 1.0
  for (var channel = 0; channel < channels; channel++) {
   // This gives us the actual ArrayBuffer that contains the data
   var nowBuffering = myArrayBuffer.getChannelData(channel);
   for (var i = 0; i < frameCount; i++) {
     // Math.random() is in [0; 1.0]
     // audio needs to be in [-1.0; 1.0]
     nowBuffering[i] = Math.random() * 2 - 1;

  // Get an AudioBufferSourceNode.
  // This is the AudioNode to use when we want to play an AudioBuffer
  var source = audioCtx.createBufferSource();
  // set the buffer in the AudioBufferSourceNode
  source.buffer = myArrayBuffer;


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

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support1412251 No156
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support Yes14 Yes26115 ? Yes

1. Firefox currently handles the value null incorrectly. Instead of producing a node that generates a single channel of silence, the node becomes unusable and will be ignored if you attempt to connect it to anything.

See also

Document Tags and Contributors

Last updated by: fscholz,