IIRFilterNode()

The IIRFilterNode() constructor of the Web Audio API creates a new IIRFilterNode object which an AudioNode processor which implements a general infinite impulse response filter.

var iIRFilterNode = new IIRFilterNode(context, options)

Inherits parameters from the AudioNodeOptions dictionary.

context

A reference to an AudioContext.

options

Options are as follows:

• feedforward: A sequence of feedforward coefficients.
• feedback: A sequence of feedback coefficients.

Unlike other nodes in the Web Audio API, the options passed into the IIR filter upon creation are not optional. The filter needs these values to work and with the vast range of filters available, there is no default.

A new IIRFilterNode object instance.

let feedForward = [0.00020298, 0.0004059599, 0.00020298];
let feedBackward = [1.0126964558, -1.9991880801, 0.9873035442];

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

const iirFilter = new IIRFilterNode(audioCtx, { feedforward: feedForward, feedback: feedBackward });