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  "title" : "Music Event Types"
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# Music Event Types

## Topics

### Constants

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

An event containing an audio unit user preset dictionary.

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

A non-MIDI music event with variable number of parameters.

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

An event that signals a change in tempo, in beats-per-minute.

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

A MIDI channel message, other than note control.

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

A MIDI note-on message, including duration.

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

MIDI system-exclusive data.

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

A standard MIDI file metaevent.

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

A null music event.

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

An audio unit parameter event.

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

User-defined data.


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