The GainNode() constructor of the Web Audio API creates a new GainNode object which is an AudioNode that represents a change in volume.
new GainNode(context, options)contextA reference to a BaseAudioContext, e.g., an AudioContext.
options OptionalOptions are as follows:
gainThe amount of gain to apply. This parameter is a- rate and it's nominal range is (-∞,+∞). The default is 1.
channelCountRepresents an integer used to determine how many channels are used when up-mixing and down-mixing connections to any inputs to the node. (See AudioNode.channelCount for more information.) Its usage and precise definition depend on the value of channelCountMode.
channelCountModeRepresents an enumerated value describing the way channels must be matched between the node's inputs and outputs. (See AudioNode.channelCountMode for more information including default values.)
channelInterpretationRepresents 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 AudioNode.channelInterpretation for more information including default values.)
A new GainNode object instance.