Hi,
You can pretty much do a lot of different strings on one instrument that is considered a "Bass", but fits better as much more than that ... and one of LA's best plays it really well, as in Don Schiff.
It's called the Chapman Stick, or just the Stick, and you can see a few pictures of Don, scroll down here a bit, and he is shown playing 2 different Sticks ... and he lays down stuff and plays over it ... and well, too! Part of a group called "The Rocket Scientists" that also features an excellent keyboard artist named Erik Norlander ... and his wife is Lana Lane, also a pretty good singer. In the 199 SF Music Festival in SF, on Saturday opening, this band put on the most professional and tight show of all the bands that day ... they were clean, polished and very good! And too many "proggies" thought this was a bit too metal ... bull ... it was just great modern stuff with magnificent keyboards and a massive bass player on the Sticks!
http://www.pedrosena.com/photos.htm