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 ⁨July 2015⁩.

ThechannelInterpretation property of theAudioNode 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 anddiscrete. These are documented inBasic concepts behind Web Audio API > up-mixing and down-mixing.

Value

The values are documented inBasic 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

const audioCtx = new AudioContext();const oscillator = audioCtx.createOscillator();const gainNode = audioCtx.createGain();oscillator.connect(gainNode);gainNode.connect(audioCtx.destination);oscillator.channelInterpretation = "discrete";