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# AudioUnitParameterUnit

The unit-of-measure for an audio unit parameter.

```
enum AudioUnitParameterUnit
```

## Overview

The various units of measure for audio unit parameters are described in `Audio Unit Parameter Units of Measure`.

## Topics

### Enumeration Cases

[`kAudioUnitParameterUnit_AbsoluteCents`](/documentation/AudioToolbox/AudioUnitParameterUnit/absoluteCents)

An absolute unit of measure for the musical pitch of a note.

[`kAudioUnitParameterUnit_BPM`](/documentation/AudioToolbox/AudioUnitParameterUnit/BPM)

A whole-number unit of measure for musical tempo, representing beats per minute.

[`kAudioUnitParameterUnit_Beats`](/documentation/AudioToolbox/AudioUnitParameterUnit/beats)

A time unit of measure in musical beats.

[`kAudioUnitParameterUnit_Boolean`](/documentation/AudioToolbox/AudioUnitParameterUnit/boolean)

A Boolean-like unit of measure.

[`kAudioUnitParameterUnit_Cents`](/documentation/AudioToolbox/AudioUnitParameterUnit/cents)

A logarithmic unit of measure for a musical interval between two notes.

[`kAudioUnitParameterUnit_CustomUnit`](/documentation/AudioToolbox/AudioUnitParameterUnit/customUnit)

A custom unit of measure.

[`kAudioUnitParameterUnit_Decibels`](/documentation/AudioToolbox/AudioUnitParameterUnit/decibels)

A logarithmic unit of measure representing the ratio between two audio levels.

[`kAudioUnitParameterUnit_Degrees`](/documentation/AudioToolbox/AudioUnitParameterUnit/degrees)

An angular degree unit of measure.

[`kAudioUnitParameterUnit_EqualPowerCrossfade`](/documentation/AudioToolbox/AudioUnitParameterUnit/equalPowerCrossfade)

An audio power unit of measure.

[`kAudioUnitParameterUnit_Generic`](/documentation/AudioToolbox/AudioUnitParameterUnit/generic)

A generic unit of measure.

[`kAudioUnitParameterUnit_Hertz`](/documentation/AudioToolbox/AudioUnitParameterUnit/hertz)

A hertz unit of measure.

[`kAudioUnitParameterUnit_Indexed`](/documentation/AudioToolbox/AudioUnitParameterUnit/indexed)

An indexed unit of measure.

[`kAudioUnitParameterUnit_LinearGain`](/documentation/AudioToolbox/AudioUnitParameterUnit/linearGain)

A linear unit of measure representing the difference between two audio levels.

[`kAudioUnitParameterUnit_MIDIController`](/documentation/AudioToolbox/AudioUnitParameterUnit/midiController)

A whole-number unit of measure corresponding to standard MIDI control numbers.

[`kAudioUnitParameterUnit_MIDINoteNumber`](/documentation/AudioToolbox/AudioUnitParameterUnit/midiNoteNumber)

A whole-number unit of measure corresponding to audio frequency.

[`kAudioUnitParameterUnit_Meters`](/documentation/AudioToolbox/AudioUnitParameterUnit/meters)

A distance unit of measure, corresponding to meters.

[`kAudioUnitParameterUnit_Milliseconds`](/documentation/AudioToolbox/AudioUnitParameterUnit/milliseconds)

A time unit of measure representing milliseconds.

[`kAudioUnitParameterUnit_MixerFaderCurve1`](/documentation/AudioToolbox/AudioUnitParameterUnit/mixerFaderCurve1)

An audio power unit of measure.

[`kAudioUnitParameterUnit_Octaves`](/documentation/AudioToolbox/AudioUnitParameterUnit/octaves)

A relative unit of measure for the musical interval between two notes.

[`kAudioUnitParameterUnit_Pan`](/documentation/AudioToolbox/AudioUnitParameterUnit/pan)

An audio position unit of measure.

[`kAudioUnitParameterUnit_Percent`](/documentation/AudioToolbox/AudioUnitParameterUnit/percent)

A percentage unit of measure.

[`kAudioUnitParameterUnit_Phase`](/documentation/AudioToolbox/AudioUnitParameterUnit/phase)

An angular degree unit of measure.

[`kAudioUnitParameterUnit_Rate`](/documentation/AudioToolbox/AudioUnitParameterUnit/rate)

A multiplication factor unit of measure.

[`kAudioUnitParameterUnit_Ratio`](/documentation/AudioToolbox/AudioUnitParameterUnit/ratio)

A unitless ratio unit of measure.

[`kAudioUnitParameterUnit_RelativeSemiTones`](/documentation/AudioToolbox/AudioUnitParameterUnit/relativeSemiTones)

A relative unit of measure for a musical interval between two notes.

[`kAudioUnitParameterUnit_SampleFrames`](/documentation/AudioToolbox/AudioUnitParameterUnit/sampleFrames)

A sample-frame-count unit of measure.

[`kAudioUnitParameterUnit_Seconds`](/documentation/AudioToolbox/AudioUnitParameterUnit/seconds)

A whole-seconds unit of measure, indicating either absolute or relative time.

[`kAudioUnitParameterUnit_MIDI2Controller`](/documentation/AudioToolbox/AudioUnitParameterUnit/midi2Controller)

## Relationships

### Conforms To

[`RawRepresentable`](/documentation/Swift/RawRepresentable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Equatable`](/documentation/Swift/Equatable)

[`BitwiseCopyable`](/documentation/Swift/BitwiseCopyable)

[`Hashable`](/documentation/Swift/Hashable)

[`Sendable`](/documentation/Swift/Sendable)

---

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