ConstantSourceNode: ConstantSourceNode() constructor

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 ConstantSourceNode() constructor creates a new ConstantSourceNode object instance, representing an audio source which constantly outputs samples whose values are always the same.

Syntax

new ConstantSourceNode(context, options)

Parameters

context

An AudioContext representing the audio context you want the node to be associated with.

options

A ConstantSourceOptions dictionary object defining the properties you want the ConstantSourceNode to have:

offset

A read-only AudioParam specifying the constant value generated by the source. The default is 1.0. The normal range is -1.0 to 1.0, but the value can be anywhere in the range from -Infinity to Infinity.

Examples

In this example, an audio context is created, then a ConstantSourceNode is established with its offset initialized to 0.5.

js
let audioContext = new AudioContext();

let myConstantSource = new ConstantSourceNode(audioContext, { offset: 0.5 });

Note: The new ConstantSourceNode created by the constructor has a channelCount of 2.

Specifications

Specification

Web Audio API
# dom-constantsourcenode-constantsourcenode

Browser compatibility

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This page was last modified on Jun 23, 2025 by MDN contributors.

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