VLSI based digital synth that was a breakthrough in voice/dollar value. 64 voice polyphony and some interesting modulation options. 76 key keyboard. S4 module has same architecture.
Always verify power supply voltages if problem looks like it could remotely be power supply related. I have seen some bad solder problems and one intermittent processor reset problem that required a new board in an Alesis product. If you must reset these this is all I've seen:
HOLD DATA BUTTONS '1' and '4' while powering on (Clears edit buffer only. there is no hard reset)
Advanced Musical Electronics has a lot of parts for Alesis stuff. THey only deal with techs though.
I've also seen All electronics carry displays occasionally at low prices. Always feel free to ask or check my Parts
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