A subtractive analog synth, very similar to CS-80 with 1 osc/voice. Same voice architecture as CS-80 and CS-50. Lots of custom chips including key decoder, DAC and all analog building blocks. Independent HP and LP filters on each synth channel and "sine feedby" vca to allow mix of a sine wave that isn't filtered. No velocity sense and only a light sensor type aftertouch. Only other synth to have the fantastic pitch ribbon of the CS-80 though, along with one "memory". (which amounts to an extra set of miniature sliders for the 'non-global functions). Also has the great ring mod.
Typical problems in CS series are power supply over voltages which blow tantalum capacitors and they short, or the caps just fail over the years. During this various chips may be taken out. I've seen LFO chip, VCA's and dac comparator fail so they might be most susceptable.
I had a most peculiar manifestation shown in a video I did on CS5. The cutoff control would just cease to impact a highly filtered sound at the Ab second from top and below or like that. It would change a note during warmup. Turned out the VCF chip was the issue!
ALso the touch strip may be rusted inside and I've seen spring on YC45D that just fell into small pieces! Fortunately it looks like a chap in UK has a precise spring replacement. He wants about 160 pounds to refurb it. The springs I got from McMaster Carr weren't quite right in diameter and I had to monkey around trying to make an actuating spacer that worked well enough I guess but if you have this issue you may want to contact him (Tom Szakaly) at email@example.com .
Slider caps and Knobs- I have a decent selection of rotary knobs (Contact Sound Doctorin') and check Synthparts.com for slider caps.
Semiconductor and Parts:
See Semiconductor page. I believe I should have any electronic part or keys for these save exact transformer, etc. Ask if you have need.
Contact Sound Doctorin'