This is going to be a toughie.

I have searched for hours for the ES/Rack ES voice category descriptions, both in the manuals and in the fora.  Nothing found.  Here is my best shot, would someone kindly add any corrections to this list that I have cobbled up?

Edited:  Added the changed noted below.  Thanks for the help.

TIA, -Mike

Ap|Acoustic Piano
Ba|Bass
Br|Brass
Co|Combination
Cp|Chromatic Percussion
Dr|Drum
Gt|Guitar
Kb|Keyboard
Ld|Lead
Me|Musical Effect
Or|Organ
Pd|Pad
Rp|Reed and Pipe
Sc|Synth Comp
Se|Sound Effects
St|Strings

ME is Musical Effect (not Mechanical)
SC is Synth Comp (a comping sound is one you can play accompaniment chords with… so a “synth comp” is always polyphonic and would be used as a rhythmic backing keyboard sound)

Otherwise you are spot on…

The Category names are actually written out in the Motif-Rack ES.

Press [VOICE] to enter Voice mode
Press the CATEGORY button
Use the BANK Buttons [<]/[>] to view the Category names

Using the Category Search function

On the Motif ES (keyboard) they are actually written on the front panel…

BM, thanks for the clarifications I have edited the list in the first append so that it doen’t throw somwone else off.  It’s good to have a correct list.
-Mike