High volume bass amp shuts off

hey guys, Gotta pickle im in.. Okay i have a type X 12'' sub in a sealed box powered by a 2 channel amp which i have bridged. so  the type X is geting 700watts rms. Now, everytime i get past about 70% of volume on most songs it cuts off. some songs that have really hard bass i can get to about 50%... some songs i cant even play cause 35% volume makes it cut off. I listen to rock and all this info is coming from listening to rock.. when i play a hip hop or rap song the bass is alot i mean alottttt louder but its like at the same 75% it shuts off. No matter how loud the bass is it still gets shut off at certain points. So heres what i did... i read alot of posts and i found that capacitors are a waste of time so i went out and got a brand new alt.. 90amps...still same problem.... then i checked my power wire like it said in the big 3...still same problem...i went to a professional..he sets the gains.... still same problem...he said get a new battery... so i went out and got a yellow top... still same problem... i am running a 4 guage power wire and i cant figure out what is it... the only thing i can figure is that the 90amps my alt is putting out... cant keep up with my power demands...but then again i was running a 1200.1 kicker amp and it was fine. i was running that system on 1 ohm and i this system im running it @ 2 ohms.... what else is there to do?I guess that guy has subs.

Just the sub cuts out when the bass hits or all music? Is the amp clipping? What knid of amp are we looking at? Have you attached a meter to the amp while your playing it where it cuts out? When this happens do you just turn it back down and it plays fine? Where do you have it grounded and have you meterd the ground?

Is the amp 2 ohm stable when bridged?There is no such thing as free installation!

tcss has this right on. The amp may be 2-ohm stable, but it is NOT 2-ohm stable when bridged. ---Very few--- amplifiers on the market are 2-ohm stable when bridged. New Project: 2003 Pathfinder

Looking at the specs. this amp is not 2 ohm stable bridged. If it was, they would make that VERY clear.The Flakman

I feel strange. I have deja vu and amnesia at the same time.

John | Manteca, CA