i thought i'd share this build that i just finished today with you guys. it's jazz bass, but with a P bass pickup in the middle position, in the same exact location as a p bass so that it'll sound basically identical to a p when the middle pickup is soloed. there are so many PJ basses out there, but i refer to this one as a 'JP'. occasionally you'll see jazz basses with a p pickup with it relocated slightly forward to fit under the pickguard but that wasn't what i was going for on this one. i also routed the j bass bridge pickup in the 60's position.
i started with a very lightweight alder jazz bass body (@ 4 1/4lbs). i shaped the contours deeper (like a 60's vintage jazz bass), then i sealed it with fullerplast and shot it with sonic blue nitro. i went with an allparts one piece maple block/bound neck on this one, stripped the stock poly finish, gave it a slight amber tint and shot it with 10 coats of clear nitro.
here's a pic of it when it was finally cured and i started the assembly:
to make the pickguard, i traced a vintage jazz bass guard onto a mint green pickguard blank and cut it out. i used a p bass guard to get the exact location of the p pickup. i also found that i had to slightly 'massage' the curve below the p bass pickup since by the pic below you can see that the p pickup's route would've been exposed if i went with a stock j bass guard's shape:
done with the exception of the mounting holes:
next, i laid it onto the body to check the fit:
i went with a Seymour Duncan SPB-1 P pickup (my personal favorite) and a Dimarzio ultrajazz bass pickup in the bridge position (so it wouldn't hum when soloed). the thing i don't care for with the new duncan and fender pickups is that their covers are super shiny and look cheap to me. i wanted more of a vintage look and also wanted it to match the duller, satin finish on the ultrajazz, so i dulled the p bass pickup covers. here's a pic of the waty that they come (left), , my dulled one (center) and an original 60's p pickup:
rather than have two volumes and a tone, the V/T/V/T stacked system or a balance control (and i prefer having a master volume), i went with a dual stacked system where the one closest to the jack is a volume for each pickup (the top one is the p and the ring is the J), and the other one is a master volume (top) with the tone control on the ring. i used stacked dual stacked 500K pots so that there would be less loss running thru all of those pots:
next i shileded the cavities with conductive paint and grounded all of them together:
then i installed the control plate and wired it up and tested it. it's completely
silent with the hum cancelling pickups and shielding.
since the body is so light, to make the bass balance without any neck dive, i went with gotoh's res-o-lite reverse tuning keys which save a ton of weight at the headstock:
i strung her up, cut the nut and adjusted the neck, action and intonation, and i gotta say, this baby sounds great!
at first i thought that the j bass pickup might be too close the D&G strings's p pickup to sound good, but that's not the case at all. it has all of the p's tone (when soloed), and does a nice j bass when they're both fully on, plus they can be blended with the stacked system to anywhere in between, and when the j bass pickup is soled, it does the 'jaco' thing very nicely. the bass is VERY resonant and it's all up weight is under 8 1/2 lbs (8lbs 6.8oz) which is actually pretty darn light for a jazz bass, especially with those heavy stacked knobs on it.