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The type
property of the OscillatorNode
interface specifies what shape of waveform the oscillator will output. There are several common waveforms available, as well as an option to specify a custom waveform shape. The shape of the waveform will affect the tone that is produced.
Syntax
OscillatorNode.type = type;
Value
A DOMString
specifying the shape of oscillator wave. The different available values are:
sine
- A sine wave. This is the default value.
square
- A square wave with a duty cycle of 0.5; that is, the signal is "high" for half of each period.
sawtooth
- A sawtooth wave.
triangle
- A triangle wave.
custom
- A custom waveform. You never set
type
tocustom
manually; instead, use thesetPeriodicWave()
method to provide the data representing the waveform. Doing so automatically sets thetype
tocustom
.
Exceptions
InvalidStateError
- The value
custom
was specified. To set a custom waveform, just callsetPeriodicWave()
. Doing so automatically sets the type for you.
Example
The following example shows basic usage of an AudioContext
to create an oscillator node. 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.start();
Specifications
Specification | Status | Comment |
---|---|---|
Web Audio API The definition of 'type' in that specification. |
Working Draft |
Browser compatibility
Feature | Chrome | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
---|---|---|---|---|---|---|
Basic support | 14 webkit | (Yes) | 23 | No support | 15 webkit 22 (unprefixed) |
6 webkit |
Feature | Android | Chrome | Edge | Firefox Mobile (Gecko) | Firefox OS | IE Phone | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|---|---|
Basic support | No support | 28 webkit | (Yes) | 25 | 1.2 | No support | No support | 6 webkit |