The out of phase sound I'm talking about is when two pickups are used together and the polarity of one of the pickups is switched. The resulting sound is kind of "nasal" or "honky." I've had two guitars that offered this sound: - A Gibson L6S which had a 6-position rotary switch that offered two out of phase sounds (serial and parallel) - An 80s PRS which had a 5-position switch that offered a serial out of phase sound. I sort of like this sound and sort of don't. I guess I'm curious if anyone has developed a passive filter of some kind (something better than your regular tone control) that would smooth out some of the peaks of this sound and make it less honky and more usable, for me anyway. Maybe a resistor/trim pot to just turn down one of the pickups would help the sound, though I'm not sure if this would work with the pickups wired in series. Ideas?