Yamaha SY99 Owner's Manual page 64

A drum voice uses 76
AWM waveforms
Voices created using mode 11 will have a different AWM waveform assigned to
each of the 76 keys (E0-G6) of the SY99. Each key also has independent set-
tings for volume, tuning, note shift, pan, etc.
This type of voice is most often used to arrange drums and percussion
sounds across the keyboard so that each key will produce a different percussive
sound. For example a bass drum might be assigned to C3, a snare to C#3, and a
cymbal to D3. Drum voices may be played from the keyboard in real time or
recorded from the keyboard into a sequencer track. Details of how to edit drum
voices are given at the end of this section.
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