A digital synthesizer which utilizes special processing chips designed to support Yamaha's FM synthesis and AWM architecture. B700 home model has many similarities apparently.
Key movement is the same on these as the other SY's except 77 and 99 it appears. I finally got one and see we were misinforming people saying they took DX type keys. Not sure who told me that. Anyway so probably the typical yamaha product with fairly high reliablity all the way around unless something gets physically broken. Except the keyboard contact strip which may need cleaning with ethanol. If it still doesn't work then I don't think it's probably available. Scrap something. The paint didn't work well when I tried it on one of these types of contact strips.
While Yamaha normally does not keep parts around more than 5 years or so, I stock what I can.
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