W3cubDocs

BaseAudioContext.createWaveShaper

The createWaveShaper() method of the BaseAudioContext interface creates a WaveShaperNode, which represents a non-linear distortion. It is used to apply distortion effects to your audio.

Syntax

baseAudioCtx.createWaveShaper();

Returns

A WaveShaperNode.

Example

The following example shows basic usage of an AudioContext to create a wave shaper node. For applied examples/information, check out our Voice-change-O-matic demo (see app.js for relevant code).

Note: Sigmoid functions are commonly used for distortion curves because of their natural properties. Their S-shape, for instance, helps create a smoother sounding result. We found the below distortion curve code on Stack Overflow.

var audioCtx = new (window.AudioContext || window.webkitAudioContext)();
var distortion = audioCtx.createWaveShaper();

  ...

function makeDistortionCurve(amount) {
  var k = typeof amount === 'number' ? amount : 50,
    n_samples = 44100,
    curve = new Float32Array(n_samples),
    deg = Math.PI / 180,
    i = 0,
    x;
  for ( ; i < n_samples; ++i ) {
    x = i * 2 / n_samples - 1;
    curve[i] = ( 3 + k ) * x * 20 * deg / ( Math.PI + k * Math.abs(x) );
  }
  return curve;
};

  ...

distortion.curve = makeDistortionCurve(400);
distortion.oversample = '4x';

Specifications

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

Browser compatibilityUpdate compatibility data on GitHub

	Desktop
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari
Basic support	10 Prefixed 10 Prefixed Prefixed Requires the vendor prefix: webkit	Yes	25	No	22 22 15 Prefixed Prefixed Requires the vendor prefix: webkit	6 Prefixed 6 Prefixed Prefixed Requires the vendor prefix: webkit