Constructor

AudioContext()

Creates and returns a new AudioContext object.

Instance properties

Also inherits properties from its parent interface, BaseAudioContext.

AudioContext.baseLatency Read only

Returns the number of seconds of processing latency incurred by the AudioContext passing the audio from the AudioDestinationNode to the audio subsystem.

AudioContext.outputLatency Read only

Returns an estimation of the output latency of the current audio context.

AudioContext.sinkId Read only Experimental Secure context

Returns the sink ID of the current output audio device.

Instance methods

Also inherits methods from its parent interface, BaseAudioContext.

AudioContext.close()

Closes the audio context, releasing any system audio resources that it uses.

AudioContext.createMediaElementSource()

Creates a MediaElementAudioSourceNode associated with an HTMLMediaElement. This can be used to play and manipulate audio from <video> or <audio> elements.

AudioContext.createMediaStreamSource()

Creates a MediaStreamAudioSourceNode associated with a MediaStream representing an audio stream which may come from the local computer microphone or other sources.

AudioContext.createMediaStreamDestination()

Creates a MediaStreamAudioDestinationNode associated with a MediaStream representing an audio stream which may be stored in a local file or sent to another computer.

AudioContext.createMediaStreamTrackSource()

Creates a MediaStreamTrackAudioSourceNode associated with a MediaStream representing a media stream track.

AudioContext.getOutputTimestamp()

Returns a new AudioTimestamp object containing two audio timestamp values relating to the current audio context.

AudioContext.resume()

Resumes the progression of time in an audio context that has previously been suspended/paused.

AudioContext.setSinkId() Experimental Secure context

Sets the output audio device for the AudioContext.

AudioContext.suspend()

Suspends the progression of time in the audio context, temporarily halting audio hardware access and reducing CPU/battery usage in the process.

Events

sinkchange Experimental

Fired when the output audio device (and therefore, the AudioContext.sinkId) has changed.

Examples

Basic audio context declaration:

const audioCtx = new AudioContext();

const oscillatorNode = audioCtx.createOscillator();
const gainNode = audioCtx.createGain();
const finish = audioCtx.destination;
// etc.

Specifications

Browser compatibility

See also

• Using the Web Audio API
• OfflineAudioContext