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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 (Gecko)	Internet Explorer	Opera	Safari (WebKit)
Basic support	10.0webkit	(Yes)	25.0 (25.0)	No support	15.0webkit 22 (unprefixed)	6.0webkit