This is an early MIDI module...maybe the first rack mount one? There is a LOT of bad information on the net about this one. I see a review saying it's all analog. First, the unit is 16Voice and has 16 analog filters and digitally controlled analog envelopes it appears from my brief overview of the diagram. But the signal generation is entirely digital. David Morely had commented somewhere it was 12 bit which would not be surprising given the age of it. That was pretty good for '84 usually. I love layering the harpsichord and electric pianos with digital sounds using the chorus and tremelo. The clav is indeed very useful as well. The pianos sound too piano except for the horribly unrealistic gritty textures :-). Alone they're a decent analog piano sound but they're kind of annoying to layer in a way with other pianos. I get better sounds for that with the MKS70.
Roland might still have some parts for these so always check there first. Let me know if you need a specific part from my listings in the parts section that you don't find elsewhere or whatever.
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