I've got a avic-f700bt and a Sony 800 xplode amp. On the paper work the amp says that it's a reverse phase. I noticed that in the sub settings, I can set reverse or normal phase. What do these changes do?

Most of the time the phase control is really just a fancy name for reversing the polarity. Just make sure everything is + to +, - to - and keep phase normal, not reversed.

Phase actually has to do with the woofers hitting and causing acoustical suffocation with mids and highs, so the logic is that you make the woofer hit inward, instead of outward to help alleviate the problem. If someone has a better expanation, feel free to jump in.

So, if my amp is a reverse, it won't hurt it running the AVIC in normal phase?

So, if my amp is a reverse, it won't hurt it running the AVIC in normal phase?

Did you specifically set your amp to be 180 degrees out of phase? If you didn't, it's probably already set in phase and you should leave the AVIC to normal. It isn't likely to burn up the sub or its driver either way, it'll just sound stupid and saggy if its wrong.

some times the sound from the subs will cancle out some of the mids and highs, thats when you want to set your phase to reverse, other wise just leave it normal(both the setting in the avic and the switch on the amp to normal or 0 degrees), also some time the subs are reverse mounted (the magnet is on the out side of the box) this is another time for the reverse phase to be turned on.

the amp should not be a "reverse phase" amp, there should be a switch to turn the phase to reverse (180 degrees) if needed.

Just listen to your music with the phase normal and reversed and see how it sounds. Back in the old days I would adjust the phase based on the mid/high frequency cut off points. Basically if you cut off your midbase speakers at a certain frequency say 125hz, the frequency from that speaker would 'invert' lower in the freq range. So then you would have to wire your subs 'backwards' in order to actually hear your base because the speakers would be cancelling each other out. In high end systems with 1000's of watts it's very noticeable, now a days, not so much. Kids and real world bills have killed that, along with worries of hearing loss as I jump into my 40's.