I have a Parker Fly (not the Washburn knockoff) that plays gorgeously, and that I can pretty much tweak to the biting upper-midrangy sound I like with this bass- that sound is really quite different from the hi-fi-ish sound these basses are usually known for.
For those unfamiliar with the electronics of this bass, here's a spec link
http://www.guitarampkeyboard.com/en/fly-bass-4/67701
The upper mid-sculpting is done by suppressing all treble (and mostly the bass) on both PU and piezo (I mostly use the bridge PU only, sometimes along with a tad of piezo blended in).
A little outboard help goes a long way in tweaking that sound even more to my liking, BUT I wonder if there is a mod that adds a mid boost control to the onboard electronics. I just like to be more independent from tagging boxes along wherever.
Given the available pots assignment and the PU/piezo architecture, the options are probably limited. I would not be averse to a mod requiring drilling in another pot if that solves it, however just swapping out one pot or the other for a stack type would be preferable.
So I guess the questions are, can I swap out just the PU part of the electronics and still keep the piezo blending option? What manufacturer offers such onboard that is compatible with the Fly's layout?
Or can the onboard electronics stay altogether, adding just that mid boost (preferably switchable frequency, or even sweepable)?
Grateful for any pointers/ideas,
Alexander