YouTube via tumblefoot. via this auction for a red Roland AX-1.

"These were made in small numbers early 90's. This is the Roland AX-1 keytar master midi controller made in Italy.
#Can send on simultaneous MIDI channels
#Responds to : velocity
#Sounds can be split by : keyboard
That means this master controller keyboard can send information to several different sound modules and be controlled from split ends of the keyboard. This straps right on like a guitar, and has functions for your left hand to do like the expression bar(really cool!!), or remote sequencer activator/octave/sound exchange. This runs off of a AA battery pack, and connects to your equipment with a single midi cable. Check out this rad synth rock band called Shy Child that uses a similar Roland keytar." video above