Keith Emerson

Again....I worked for Kurzweil and owned all of these instruments. Keith was endorsed by Kurzweil Music Systems in the 80s, with a K250 and a Midiboard. Both were used on the EL Powell album and can be seen in music videos and on live concert footage. I also got to see Keith's rig in person. Keith triggered sounds from a Yamaha TX-816 and an Overheim Matrix 12 with his MidiBoard. That's where the big brass lead for "The Score" and "Touch and Go" came from. In later years, he switched to cheaper, thinner synths like the Korg O1W and an Alesis. Neither ever captured the magic of the original FM/OB analog layers. Or the GX-1 for that matter.

I worked with Kurzweil in the 80s and owned a K250 Expander and MidiBoard. You can clearly see the K250 on the left side of Keith's 1986 keyboard rig. You can also clearly hear the very distinctive K250 CHOIR patch from Sound Block A all over "The Score" - both live and on the studio recording. You can hear the K250 percussion (claps, snaps and shakers) all over Touch & Go as well. The "Endless Glissando" patch as well as the K250 choir and strings are all over "Mars, The Bringer of War."

The MidiBoard is the large 88 note controller placed on top of his GX-1. See the video.

This Sound On Sound article states that Emerson owned a Korg SQ-10.