Idle Drops and Belt Squeaks When Bass Hits

I have a 1993 Toyota celica with a recently added m2000d amp running 2 12 machete super sports. After upgrading adding the speakers and amp the idle drops when the bass hits and the belt squeaks like mad. I put a 180 amp high output alternator in to fix this but it seems to make no difference. I checked all my grounds over and over again(recently did big 3), not sure what else to check, only thing I can think of is the battery is too small or my capacitor is not working right. Any suggestions?

Your alternator puts out a lot less than it's max rating at idle. Assuming your belt is in good condition and tensioned properly, turn down your volume at idle. You might also search for a smaller alternator pulley (more mechanical drag on the engine, but would spin it faster).My ex once told me I have a perfect face for radio.