ConvolverNode

The ConvolverNode interface is an AudioNode that performs a Linear Convolution on a given AudioBuffer, often used to achieve a reverb effect. A ConvolverNode always has exactly one input and one output.

[!NOTE] For more information on the theory behind Linear Convolution, see the Convolution article on Wikipedia.

Number of inputs	1
Number of outputs	1
Channel count mode	"clamped-max"
Channel count	1, 2, or 4
Channel interpretation	"speakers"

Constructor

• ConvolverNode()
  • : Creates a new ConvolverNode object instance.

Instance properties

Inherits properties from its parent, AudioNode.

• buffer
  • : A mono, stereo, or 4-channel AudioBuffer containing the (possibly multichannel) impulse response used by the ConvolverNode to create the reverb effect.
• normalize
  • : A boolean that controls whether the impulse response from the buffer will be scaled by an equal-power normalization when the buffer attribute is set, or not.

Instance methods

No specific method; inherits methods from its parent, AudioNode.

Examples

The following example shows basic usage of an AudioContext to create a convolver node. You will need to find an impulse response to complete the example below. See our HolySpaceCow example for a complete, applied example.

let audioCtx = new window.AudioContext();

async function createReverb() {
  let convolver = audioCtx.createConvolver();

  // load impulse response from file
  let response = await fetch("path/to/impulse-response.wav");
  let arraybuffer = await response.arrayBuffer();
  convolver.buffer = await audioCtx.decodeAudioData(arraybuffer);

  return convolver;
}

// …

let reverb = await createReverb();

// someOtherAudioNode -> reverb -> destination
someOtherAudioNode.connect(reverb);
reverb.connect(audioCtx.destination);

Specifications

Browser compatibility

See also

• Using the Web Audio API