Need a deeper, "punchy" tone from my jazz

[pacojas]

and i always thought "punch" was in the fingers. i must be doing it wrong!

 

[blindrabbit]

and i always thought "punch" was in the fingers. i must be doing it wrong!

Yes, you are. You punch with your fist, not your fingers. I'm surprised you haven't broken them yet if that's what you are trying to do...

 

[20db pad]

Sadowsky outboard preamp.

 

[4StringTheorist]

My suggestions in order from low-$ to high-$

1. Flatten your amp EQ. Quit boosting the low end if you already are. IN fact, possibly cut the bass and treble just a bit. Then bump up your volume to compensate. This will bring the punchy midrange forward. Now that the overall amp volume is up higher, a very little bit of bass EQ bump goes a very long way.
   
   
2. New strings! Try the ones people have listed here. These first two can make as big a difference as pickups but at a fraction of the cost.
   
   
3. New pickups. Again, lots of good suggestions here.