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# Effect Audio Unit Subtypes

Effect (digital signal processing) audio unit subtypes for audio units provided by Apple.

## Topics

### Constants

[`var kAudioUnitSubType_AUiPodEQ: UInt32`](/documentation/AudioToolbox/kAudioUnitSubType_AUiPodEQ)

An audio unit that provides a graphic equalizer in iOS.

[`var kAudioUnitSubType_BandPassFilter: UInt32`](/documentation/AudioToolbox/kAudioUnitSubType_BandPassFilter)

[`var kAudioUnitSubType_Delay: UInt32`](/documentation/AudioToolbox/kAudioUnitSubType_Delay)

An audio unit that introduces a time delay to a signal.

[`var kAudioUnitSubType_Distortion: UInt32`](/documentation/AudioToolbox/kAudioUnitSubType_Distortion)

[`var kAudioUnitSubType_DynamicsProcessor: UInt32`](/documentation/AudioToolbox/kAudioUnitSubType_DynamicsProcessor)

[`var kAudioUnitSubType_HighPassFilter: UInt32`](/documentation/AudioToolbox/kAudioUnitSubType_HighPassFilter)

[`var kAudioUnitSubType_HighShelfFilter: UInt32`](/documentation/AudioToolbox/kAudioUnitSubType_HighShelfFilter)

An audio unit suitable for implementing a treble control in an audio playback or recording system.

[`var kAudioUnitSubType_LowPassFilter: UInt32`](/documentation/AudioToolbox/kAudioUnitSubType_LowPassFilter)

An audio unit that passes frequencies below a specified cutoff frequency, and blocks frequencies above that cutoff frequency.

[`var kAudioUnitSubType_LowShelfFilter: UInt32`](/documentation/AudioToolbox/kAudioUnitSubType_LowShelfFilter)

An audio unit suitable for implementing a bass control in an audio playback or recording system.

[`var kAudioUnitSubType_NBandEQ: UInt32`](/documentation/AudioToolbox/kAudioUnitSubType_NBandEQ)

[`var kAudioUnitSubType_ParametricEQ: UInt32`](/documentation/AudioToolbox/kAudioUnitSubType_ParametricEQ)

An audio unit that provides a filter whose center frequency, boost/cut level, and Q can be adjusted.

[`var kAudioUnitSubType_PeakLimiter: UInt32`](/documentation/AudioToolbox/kAudioUnitSubType_PeakLimiter)

An audio unit that enforces an upper dynamic limit on an audio signal.

[`var kAudioUnitSubType_SampleDelay: UInt32`](/documentation/AudioToolbox/kAudioUnitSubType_SampleDelay)

An audio unit that provides a time delay for a specified number of samples.

[`var kAudioUnitSubType_AUSoundIsolation: UInt32`](/documentation/AudioToolbox/kAudioUnitSubType_AUSoundIsolation)

[`var kAudioUnitSubType_Reverb2: UInt32`](/documentation/AudioToolbox/kAudioUnitSubType_Reverb2)


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