A downscaled D-50 (losing chorus and other fx, and pwm, but with 32 voices instead of 16 plus more samples. D20 adds 8 track sequencer also.
Other than key cleanings and some dirty buttons I haven't seen much trouble with these machines.
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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