Yamaha CSY-1 SN 2810

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."