Many boutique manufacturer like Nordstrand, etc. can put their "Jazz" pickups in whatever size casing you desire. It will cost more. Emg offers their Jazz pickups in soapbar shapes off the shelf. You'll have to measure your "soapbars" to see what size they are.
^ +1. Also, if you ever want to solo either pickup in a noiseless fashion, Nordy big splits. They've worked out really well for a jazz tone in my Valenti.
indeed Nordstrand can make pretty much any coil combination in a soapbar shape (no Pbass pup, tho). Keep in mind that a 'Jazz bass' sound is also determined by the placement of pickups related to the scale. M
+1 on the Nordstand Big Singles. However, I must say that the Big Singles will vary in sound depending on the woods of the bass. They really sound best on basses with ash, maple, or alder. I have heard the new Ibanez SR1200 series, most of which have mahogany and ovangkol, with the Big Singles and they somehow don't have that jazz bass sound, in my opinion. EMG also makes single coil pickups in soapbar sizes. The good thing about the EMGs is that they are dead quiet! No noise!
I had a pair of these in one of my basses for a few years. The bass wasn't anything like a Fender, so neither was the result. The maker said it was just his Jazz pu in a soapbar case though, FWIW. I only changed them out because I really need humbuckers, they sounded great otherwise.
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