Yamaha CSY-1 Rare Vintage Analog Synth Organ

via this auction
"This is the rarely seen Yamaha CSY-1 synth/organ combination. Yamaha's first ever synth was the SY-1 introduced in 1974, they also decided to build the SY-1 into a 2 manual plus pedalboard type organ cabinet and that's what we have here, the CSY-1.

This really is a fun piece of kit with some great sounds, very expressive too thanks to Yamaha's aftertouch (amazing for 1974) which can be assigned to different parameters. Although a preset synth it's editable, so the presets are just a starting point for sound creation. The synth section is playable from the upper keyboard OR the bass pedalboard. It can be played solo or can be combined with the organ sounds/bass sounds. The CSY-1 has it's own built in amplification/speakers, spring reverb and even a real Leslie type rotary speaker, the synth section sounds great routed through this.

To get an idea of the sound go to YouTube and search for Yamaha SY-1 or SY-2 (the SY-2 is another model variation in a road case)

I must say, old Yamaha gear is incredibly reliable, superb build quality. Also, I read somewhere that the CSY-1 shares much of it's circuitry, particularly the filters, with the monosynth section of the mighty Yamaha GX-1 synth (introduced about a year later), there certainly are sound similarities if you check them both out."

SY-1 posts including vids
SY-2 posts including vids