I am installing a fishman powerchip in a custom build. The setup is- A DiMarzio magnetic pickup with a volume control, A fishman powerchip for the piezo bridge, and it all works the way it should. I installed according to the powerchip instructions with the 3 way switch for selecting Mag/Piezo/both. The instructions are here- http://www.fishman.com/files/powerchip_user_guide.pdf What I cannot figure out is how to wire a master tone. I can wire a tone that works on the DiMarzio only easily enough, but for the life of me, I WANT A TONE CONTROL ON THE PIEZO!!!! All the signals rout through the powerchip and my head tells me that a tone pot wired to the output and bleeding signal to ground should work, but nada. Perhaps I am using the wrong value pot and cap- standard B500K and a .047....An outboard unit is not an option. As far as I can tell the lack of a tone control on the powerchip is perhaps a fault in design...but I have to work with what I have. Any help would be appreciated!!!