BiquadFilterNode.Q

The Q property of the BiquadFilterNode interface is an a-rate AudioParam, a double representing a Q factor, or quality factor.

It is a dimensionless value with a default value of 1 and a nominal range of 0.0001 to 1000.

Syntax

var audioCtx = new AudioContext();
var biquadFilter = audioCtx.createBiquadFilter();
biquadfilter.Q.value = 100;

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;

biquadFilter.type = "peaking";
biquadFilter.frequency.value = 1000;
biquadFilter.Q.value = 100;
biquadFilter.gain.value = 25;

Specifications

Specification
Web Audio API # dom-biquadfilternode-q

Browser compatibility

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	WebView Android	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet
`Q`	14	12	25	No	15	6	≤37	18	25	14	Yes	1.0