This unit was Yamaha's attempt to put a computer and a FM synthesizer into one package. It was fairly well done, using the MSX operating system as a platform. Certainly it looked cool, with it's black case and matching disk drive, but the lack of a velocity sensitive keyboard and some limitations in the software made many people look elsewhere.
Comments About the Sounds:
Using the (step-time only) sequencing ROM cartridge, I spent many fairly happy (if not exactly social) hours programming music of all kind. It took a particular kind of mindset to arrange everything in your head and play it back (only from the beginning each time) to hear the results on one's insanity and insomnia. But it was affordable (where the combination of Macintosh/Performer/Major-midi-keyboard was not). You just had to trade in your sanity. It was like composing on manuscript paper. I love the things that I did using it, am impressed that I did do them and am grateful that I never have to use the bastard ever again. The sounds are cool: cutting edge 4-operator FM. The patch writing card makes it all pretty graphical and interesting. And there are definitely some cool sounds you can get out of it. And yet, and yet. I keep mine as a reminder of how difficult things used to be for me.
(Thanks to Chris Cebelenski for this info.)
and Wayne Jacobs for the pic