Wassup guys...Im looking into uprgading my current system: Sony xm-D9001GTR mono amp (550w @ 4 ohm/ 900w @2 ohms) pushing some new Sony XS-L123P5B 12's 330w RMS 1300peak blah blah....nothing too spectacular but due to the size of my sealed box, they hit pretty decent... Was debating switching to 2 of the AA Assassin Series 12"D4...im guessing I cant push these at 2ohm due to the amp and them being DVC 4 ohm subs and technically they'd probably run best a 4 ohms on this amp(550w)... For the hardest hit, should I just run 2 at 4 ohms(550w) in my current sealed box which is pretty big(dont know exact specs on it, maybe like 2.5ft in each chamber )...or run 4 of them at 2 ohms(900w) to get the most out of my amp in a 4 chamber box w/ 2.1 ft in each chamber? Oooor....should I focus on a one sub set-up like a 15" AA Havoc Series 15"D2 and get a box built for it?? I dont think my amp would push that sub anyway...since I just got this amp Im really tryna build around it, despite what alot of people think about sony, there new amps are actually pretty decent....thanks alot