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BiquadFilterNode.gain

The gain property of the BiquadFilterNode interface Is a k-rate AudioParam, a double representing the gain used in the current filtering algorithm.

When it takes a positive value it is a real gain, when negative it is an attenuation.

It is expressed in dB, has a default value of 0 and can take a value in a nominal range of -40 to 40.

Syntax

var audioCtx = new AudioContext();
var biquadFilter = audioCtx.createBiquadFilter();
biquadfilter.gain.value = 25;

Note: Though the AudioParam returned is read-only, the value it represents is not.

Value

An AudioParam.

Example

The following example shows basic usage of an AudioContext to create a Biquad filter node. For a complete working example, check out our voice-change-o-matic demo (look at the source code too).

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

//set up the different audio nodes we will use for the app
var analyser = audioCtx.createAnalyser();
var distortion = audioCtx.createWaveShaper();
var gainNode = audioCtx.createGain();
var biquadFilter = audioCtx.createBiquadFilter();
var convolver = audioCtx.createConvolver();

// connect the nodes together

source = audioCtx.createMediaStreamSource(stream);
source.connect(analyser);
analyser.connect(distortion);
distortion.connect(biquadFilter);
biquadFilter.connect(convolver);
convolver.connect(gainNode);
gainNode.connect(audioCtx.destination);

// Manipulate the Biquad filter

biquadFilter.type = "lowshelf";
biquadFilter.frequency.value = 1000;
biquadFilter.gain.value = 25;

Specifications

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

Browser compatibility

Feature Chrome Edge Firefox Internet Explorer Opera Safari
Basic support 14 Yes 25 No 15 6
Feature Android webview Chrome for Android Edge mobile Firefox for Android IE mobile Opera Android iOS Safari
Basic support Yes 14 Yes 26 No 15 ?

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/BiquadFilterNode/gain