I have a modified, partly unoriginal Fender Jazz from '71, and I am not really happy with the sound of it. It is medium-heavy ash + maple board and baseball bat neck.
The electronics are '75 Fender Jazz reissues paired with a Glockenklang 2-band preamp. As soon as I turn up the treble just a tad, the sound gets very thin, and I need to apply a bass boost at all times to make it sound decent to begin with.
By chance, I have just acquired a pair of Bartolini - 57J1 L/S. Since these are humbuckers they should have a darker sound which might suit the inherent qualities of this rather thin-sounding bass and make it come alive. There wouldn't be any problem pairing these pickups with the Glockenklag electronics, would there?