I'm not doing it myself, and I have no real knowledge about how pickups are wired at all. I do know my Carvin has a complex setup. I have active/passive electronics with coil splitters and a phase switch. I want to get new pickups installed; I'm not sure what exactly yet, but they'd be passive for sure. One of the volume knobs is a push/pull knob that switches between passive and active, so I was thinking of somehow getting it wired so this switches between Piezo pickups and my regular pickups.

So basically, what I want to do is get rid of the active electronics, install Piezos, new pickups, and somehow switch between them with the volume knob, instead of a separate switch. Is this possible?

It's a Carvin DC727. https://www.carvinguitars.com/catalog/guitars/index.php?model=dc727
Maybe U2 wouldn't suck so hard if they stopped preaching and started rocking instead. Of course, that's difficult to do with Pantera holding a near monopoly on all things that rock.
Looks like there's quite a job there.... I think with a push/pull volume pot, you might be able to switch between pickups with it, but why do you want passives?
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nothing wrong with passives and with passives you get wider range of tonal possibilities.
Gear: I haz some

Quote by RCA1186
hah its ok besa, i still love you

^ guess someone has too