I really do like the passive Jazz bass. I'd like to add an active bass at some point, but I have found the passive Jazz to be a pretty flexible instrument. You can get some pretty bright, forward sounds or darker, thicker sounds, and a fair amount in between. I've only had a Jazz bass for a little while, but I discovered a lot of those tones myself, just playing around.
Fender Jazz Bass Club #1021,Blues Bass Players Club #172
Lefties Who Play Righty Club #288