What preamps fit into an unmodified jazz control route? I was considering the installing a NTBT into the unmodified control cavity and having a battery box routed. I'd actually prefer a 3 band eq but isn't the mid redundant if I have treble and bass - couldn't I adjust the treble and bass to simulate raising or lowering the mids? ie. - if I boosted the treble and bass together wouldn't that be the same as lowering the mids and if I lowered the treble and bass together wouldn't that be like boosting the mids? Am I completely wrong. The j-retro is very nice but out of my price range.