Last Roland keyboard before memory entered the picture with JP4 and Promars. A fairly typical subtractive using a few unusual parts I believe but someday I'll try to add more details.
I have only the rotating knobs I believe for these. 5 each for the large ones I believe that these take but ask for precise measurements as I've never seen one of these up close.
Roland still stocks many parts for older instruments! You can always order them through your local Service Center and see what happens! Otherwise I have some parts also so don't hesitate to ask.
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