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Jay Wasco's Swiss Army bass - an inconveniently unique instrument; hard to play, interesting to hear -

Yup-that's right. It's a bass guitar with a midi keyboard mounted on it. Yes, the two are played simultaneously. The bass is played with the left hand alone by means of a guitar technique known as "hammer-ons" while the keyboard (which emulates a distorted slide guitar most of the time. among other things) is played with the right hand. This instrument has a weight equivalent to that of a small motorcycle, and as you might imagine, requires years of time and patience to "master".

While you're there, check out the Egotar, bass/slide guitar hybrid -Link

Related:

weird bass guitars -Link