http://www.vintagevibeguitars.com/windows/jbassWin.html
The link above is to what I have in my 75 RI. I like them a lot. Enough that I pulled the Audere pre out and went back to passive in that bass. I do like the Audere a lot but - I need to have passive basses as well and this one just it!
My L-2500 still has a 3ZB and I have an in-bound 5-01 that will very likely get a 3ZB as well...
Tonally this are full range. Not an overly heavey bottom or top which I think makes them flexible. The pickups are wax potted under vacuum and then copper foil shielded using a separate braided ground. It's about as quiet as you can get with a single coil.
The Lawrence J45 would be the other pickup I would think about. Clear and quiet. Big attack. I prefer the Vintage Vibe for it's more well vintage character - that's what I want from a J - those are both great pickups though. The Lawrence is a steal at just over a hun per pair. The JBX-4's are fully custom, built to order in Pete's shop. You can spec magnet materials, overwind, underwind, etc - the build quality is the best I've ever seen in any other pickup except a Dark Star. High praise I think. As Fred Hammon's pickups are simply a functional work of art, so are Pete Biltoft's ...
The other thing I might think about - string selection. I'm really high on what I get from the Thomastic Super Alloy. It's a meatier sounding round. Slap
s very well IMO. Not overly brite, great definition. More booty than many competing stings I've tried. (note - I suxk at slapping, people pay me to not slap in public unless it's a pie throwing contest ...

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