Ok currently I have two 12" Sony XS-L122P5 12" (350wrms @ 4ohms) hooked up to a 2 channel amp. Both are running 300wrms, heres the problem, the amp freq. range is from 40hz-150hz....which is horrible. So I'm thinking about getting a new amp which is the Sony XM-SD61X http://www.sonicelectronix.com/item_5027.html. My question is, will running the amp at 600w @ 2ohms see the 4 ohm subs and power each equally? I'll be wiring them in parallel, so that should work right? My other question is about my box, they are in a bandpass box which sounds pretty good, but I'm wondering if they were in a sealed box would it be better?