MDN’s new design is in Beta! A sneak peek: https://blog.mozilla.org/opendesign/mdns-new-design-beta/

The OscillatorNode interface represents a periodic waveform, such as a sine wave. It is an AudioScheduledSourceNode audio-processing module that causes a specified frequency of a given wave to be created—in effect, a constant tone.

An OscillatorNode is created using the AudioContext.createOscillator() method. It always has exactly one output and no inputs. Its basic property defaults (see AudioNode for definitions) are:

Number of inputs 0
Number of outputs 1
Channel count mode max
Channel count 2 (not used in the default count mode)
Channel interpretation speakers

Constructor

OscillatorNode()
Creates a new instance of an OscillatorNode object, optionally providing an object specifying default values for the node's properties.  If the default values are acceptable, you can simply call the AudioContext.createOscillator() factory method.

Properties

Inherits properties from its parent, AudioScheduledSourceNode, and adds the following properties:

OscillatorNode.frequency
An a-rate AudioParam representing the frequency of oscillation in hertz (though the AudioParam returned is read-only, the value it represents is not). The default value is 440 Hz (a standard middle-A note).
OscillatorNode.detune
An a-rate AudioParam representing detuning of oscillation in cents (though the AudioParam returned is read-only, the value it represents is not). The default value is 0.
OscillatorNode.type
A string which specifies the shape of waveform to play; this can be one of a number of standard values, or custom to use a PeriodicWave to describe a custom waveform. Different waves will produce different tones. Standard values are "sine", "square", "sawtooth", "triangle" and "custom". The default is "sine".

Methods

Inherits methods from its parent, AudioScheduledSourceNode, and adds the following:

OscillatorNode.setPeriodicWave()
Sets a PeriodicWave which describes a periodic waveform to be used instead of one of the standard waveforms; calling this sets the type to custom. This replaces the now-obsolete OscillatorNode.setWaveTable() method.

Examples

The following example shows basic usage of an AudioContext to create an oscillator node and to start playing a tone on it. For an applied example, check out our Violent Theremin demo (see app.js for relevant code).

// create web audio api context
var audioCtx = new (window.AudioContext || window.webkitAudioContext)();

// create Oscillator node
var oscillator = audioCtx.createOscillator();

oscillator.type = 'square';
oscillator.frequency.value = 440; // value in hertz
oscillator.connect(audioCtx.destination);
oscillator.start();

Specifications

Specification Status Comment
Web Audio API
The definition of 'OscillatorNode' in that specification.
Working Draft  

Browser compatibility

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari (WebKit)
Basic support 14 webkit (Yes) 25 No support 15 webkit
22 (unprefixed)
6 webkit
constructor 55.0 ? ? ? 42 ?
Feature Android Android Webview Edge Firefox Mobile (Gecko) Firefox OS IE Phone Opera Mobile Safari Mobile Chrome for Android
Basic support No support (Yes) (Yes) 25 1.2 No support No support webkit 28 webkit
constructor No support 55.0 ? ? ? ? 42 ? 55.0

See also

Document Tags and Contributors

 Last updated by: lazarljubenovic,