Hi -- I've got a bass with a Bart 3-band, 18v preamp. Its wired up with a Bart piezo buffer, and the mags are 2 Bart X-series pups. What I'm curious about is whether or not I can convert the regular pup blend pot to two individual volume pots with this configuration. Then, I'll be curious as to if I can convert the mag-piezo blend into an independent volume for the piezo's... Any help would be great. Thanks!