index.md

title	short-title	slug	page-type	browser-compat
AnalyserNode: AnalyserNode() constructor	AnalyserNode()	Web/API/AnalyserNode/AnalyserNode	web-api-constructor	api.AnalyserNode.AnalyserNode

{{APIRef("'Web Audio API'")}}

The AnalyserNode() constructor of the Web Audio API creates a new {{domxref("AnalyserNode")}} object instance.

Syntax

new AnalyserNode(context)
new AnalyserNode(context, options)

Parameters

• context

  • : A reference to an {{domxref("AudioContext")}} or {{domxref("OfflineAudioContext")}}.

• options {{optional_inline}}

  • : An object with the following properties, all optional:

    • fftSize
      • : The desired initial size of the FFT for frequency-domain analysis. The default is 2048.
    • maxDecibels
      • : The desired initial maximum power in dB for FFT analysis. The default is -30.
    • minDecibels
      • : The desired initial minimum power in dB for FFT analysis. The default is -100.
    • smoothingTimeConstant
      • : The desired initial smoothing constant for the FFT analysis. The default is 0.8.
    • channelCount
      • : Represents an integer used to determine how many channels are used when up-mixing and down-mixing connections to any inputs to the node. (See {{domxref("AudioNode.channelCount")}} for more information.) Its usage and precise definition depend on the value of channelCountMode.
    • channelCountMode
      • : Represents an enumerated value describing the way channels must be matched between the node's inputs and outputs. (See {{domxref("AudioNode.channelCountMode")}} for more information including default values.)
    • channelInterpretation
      • : Represents an enumerated value describing the meaning of the channels. This interpretation will define how audio up-mixing and down-mixing will happen. The possible values are "speakers" or "discrete". (See {{domxref("AudioNode.channelCountMode")}} for more information including default values.)

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

• {{domxref("BaseAudioContext.createAnalyser()")}}, the equivalent factory method