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# AVAudioUnitEQFilterParameters

An object that encapsulates the parameters that the equalizer uses.

```
class AVAudioUnitEQFilterParameters
```

## Overview> Note:
> Don’t create an instance of the `AVAudioUnitEQFilterParameters` class directly. Use the array that returns from the ``doc://com.apple.avfaudio/documentation/AVFAudio/AVAudioUnitEQ/bands`` property of ``doc://com.apple.avfaudio/documentation/AVFAudio/AVAudioUnitEQ``.

## Topics

### Getting and Setting Equalizer Filter Parameters

[`bandwidth`](/documentation/AVFAudio/AVAudioUnitEQFilterParameters/bandwidth)

The bandwidth of the equalizer filter, in octaves.

[`bypass`](/documentation/AVFAudio/AVAudioUnitEQFilterParameters/bypass)

The bypass state of the equalizer filter band.

[`filterType`](/documentation/AVFAudio/AVAudioUnitEQFilterParameters/filterType)

The equalizer filter type.

[`frequency`](/documentation/AVFAudio/AVAudioUnitEQFilterParameters/frequency)

The frequency of the equalizer filter, in hertz.

[`gain`](/documentation/AVFAudio/AVAudioUnitEQFilterParameters/gain)

The gain of the equalizer filter, in decibels.

### Constants

[`AVAudioUnitEQFilterType`](/documentation/AVFAudio/AVAudioUnitEQFilterType)

Filter types available to use with the filter type property.


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