phase shift

[Callen]

First off, let me say that I just got my 12 incher installed, and boy does it pound... I got an Audiobahn Enclosure with a 400 watt RMS sub covered by a 400 watt Audiobahn Amp (A1801Q). I'm trying to tweak the thing around as to not kill it too easily, and was wondering what the phase shift exactly does? I understand the Low pass X-over, and the subsonic filtering along with gain control, and Bass Boost, but i'm not sure as to the difference between 0 and 180 degrees. Thanks for all post-posts, they're greatly appreciated.

[Luc]

Phase shift is adjusting the signal tone from the amp, so that the subwoofer beat will be "in phase" with the car speakers. It's like time correction, but less complexity. Of course, you can always adjust the tone to be out-of-phase, but that won't sound too good.