Divide down circuit with selections for 16' and 8'passive filtered waveforms. Sounds like an organ bass as one would expect. Fairly rare I think. I worked on serial #A44 and mostly likely it was as with the DS-1 where the -2 quickly followed with some improvements.
Get a headphone amp or something to listen to each pin of the TOS to make sure frequencies aren't missing. Go to Organ Service corps TOS page for a diagram of the pinout of SAJ110 and also verify those.
Otherwise just dirty issues usually on these unless they're abused. Or eventually probably failing electrolytics. The Italians seemed to get better ones than some others though. I don't see many problems with them yet.
I have the TOS. Organ service corp has SAJ110 last I checked. Recommend getting SAJ210 or SAA1004N for better reliability
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