AudioNode: channelInterpretation property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since April 2021.

The channelInterpretation property of the AudioNode interface represents an enumerated value describing how input channels are mapped to output channels when the number of inputs/outputs is different. For example, this setting defines how a mono input will be up-mixed to a stereo or 5.1 channel output, or how a quad channel input will be down-mixed to a stereo or mono output.

The property has two options: speakers and discrete. These are documented in Basic concepts behind Web Audio API > up-mixing and down-mixing.

Value

The values are documented in Basic concepts behind Web Audio API > up-mixing and down-mixing.

In summary:

speakers

Use set of "standard" mappings for combinations of common speaker input and outputs setups (mono, stereo, quad, 5.1). For example, with this setting a mono channel input will output to both channels of a stereo output.

discrete

Input channels are mapped to output channels in order. If there are more inputs that outputs the additional inputs are dropped; if there are fewer than the unused outputs are silent.

Examples

js
const audioCtx = new AudioContext();

const oscillator = audioCtx.createOscillator();
const gainNode = audioCtx.createGain();

oscillator.connect(gainNode);
gainNode.connect(audioCtx.destination);

oscillator.channelInterpretation = "discrete";

Specifications

Specification
Web Audio API
# dom-audionode-channelinterpretation

Browser compatibility

BCD tables only load in the browser

See also