The 4001 model features a neck through construction, a full-wood body, fret board with metal strings (originally flat-wound, though many players replaced them with round-wounds), I use flat wound strings for a more bluesy sound. It also has twin truss rods, triangle inlays, two pickups, two volume and two tone dials, selector switch,and wiring for Rick-O-Sound. Rick-O-Sound can be used to produce special effects and multi-channel output when used with a stereo amp, a dual channel amp, or two separate amps. I have used a Peavey Centurion Mark III Series 260c Amp because it has two inputs and two outputs to get a stereo effect where one speaker puts out a high end sound and one puts out a low end sound a very interesting effect when playing a live gig. To get the best sound from the Rickenbacker 4001 stereo bass I tune it just a touch sharp. I like the full all around sound you get from the Rickenbacker Bass. Some artist that play the Rickenbacker Bass are Geddy Lee of Rush, Cliff Burton of Metallica, Geezer Butler of Black Sabbath, and Stu Cook of CCR, just to name a few.