I picked up an old Yamaha CS15 from a friend, and upon powering the beast up, I found that the notes drone on endlessly regardless of what settings I use in the EG sections. There is no switch for a drone or a hold, and it can't be a keyboard issue because the note that sustains is the note you just pressed. I've tried everything, setting all EG parameters to zero, and still nothing. Also, I can hear the attack and the decay change, but not the release. What could be causing this issue? Also, there is a switch that was added to the front panel, looks like a mod. The wires of the switch go underneath what seems to be a missing trimpot in the EG section of the PCB. The switch does not affect the sound in any way.
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Help! Yamaha CS15 notes sustain indefinitely-- no release!
2010-10-01 by Mark