Yep, that keyboard is definitely bad*$$! And quite a bit of history, being a forerunner to the CS80. I get fascinated by the technology and features of some of these Classic keyboards, and by what they did with the technology back then. But for over fifty grand, it definitely should've been something special!
I once had a Yamaha D80 organ, and I had no idea about it at the time, but as far as I can tell, that organ also had CS80 technology in it, but without all of the editing features, such as ADSR envelope generators. It did have a cool mono-synth third keyboard, like this GX-1, and while that keyboard also did not have directly controllable filters and envelope generators, it did have portamento.
The Yamaha E70 is another Classic organ with this technology, with more features than the D80 but without the third keyboard. And unlike the $20-grand that a CS80 goes for these days, you might be able to find an E70 for something like $500! There are also additional models like the D85, 415, and E75 that may be worth checking out.
