The data bytes of a note-on message represent the pitch and . In most cases, a pitch value of 0 represents C below subcontra C (called C0 in MIDI notation), 12 represents subcontra C (or C1), 60 is middle C (or C5), and so on. For drum kits, the data byte instead represents a particular drum sound. For example, as long as the General MIDI (GM) percussion key map is being adhered to, a value of 60 represents a high bongo sound. Channel 10 is reserved for drum kits.
For information on how DirectMusic converts to and from MIDI notes, see Music Values and MIDI Notes.