QuickTime Music Architecture

Knob Event

The knob event is used to modify a particular knob or knobs within a specified part.

Figure 12 Knob event

Table 9 Contents of a knob event

Knob event type	First nibble value = `1111` (general event), subtype 7
Length	Length of the event will be 2(#knobs+1)
Part	Unique part identifier
Knob ID	Knob ID within specified part
Knob value	Knob value
Event tail	First nibble of last word = `11XX` , subtype 7

The part field contains the unique part identifier initially used during the TuneSetHeader call.

The knob number bit field identifies the knob to be changed.

The 32-bit value composed of the lower 16-bit and upper 16-bit field values is used to alter the specified knob.