I remember what turned me on to the single-pickup 4000 - when I played a Jazz Bass almost exclusively, 99.9% of the time I had both pickups on full volume. With my 4001, I either used both together or just the neck pickup. But once I made a recording and someone at the RickResource Forum made some comment that
his bass "screams" or or was brighter or something like that. I took that as a challenge and went back and rerecorded the bass part just using the bridge pickup. I boosted the bass frequencies with my preamp, and it sounded amazing! I never would have guessed, because usually going from both or the neck pickup to the bridge pickup always sounds incredibly thin to me.
But if you think about it, the 4000 is kind of like a P-Bass to the Jazz Bass of the 4001/4003.
The other thing that got me wanting a 4000 was this video:
http://youtube.com/watch?v=lFP-alYNq5I(And just for fun, though off topic, here's the same song being performed recently:
http://youtube.com/watch?v=2r123KZbXUs&feature=relatedLooks like Stanley's playing his Spellbinder bass instead of an Alembic - some people at the Alembic Club are going to be bummed...)