I have a P bass coming that has a Piezo pickup under the bridge, so I'll need some sort of preamp/buffer for the piezo. It's been parted out somewhat, so I don't have a preamp or P pickup yet. I'm hoping I can get the following setup : 1. Piezo Buffer (can it be a switch?) 2. EMG Treble/Bass Expander 3. Low Pass final Stage (Or just some kind of tone control) However I'm unsure how to wire that up since nobody makes anything like that in one unit. The bass I have coming is already routed for a 18v battery box. My thought for this control scheme is I can blend some piezo and magnetic tone, dial in the amount of scoop I want, and then low pass out noise (or exploit for resonant bump).