I have a Boston acoustics pro 12.5 sub(4 ohms) in custom box at Boston specs (sealed 1” mdf). It is rated at 1200w rms and iam now using a 600w rms(Hertz class D). Although it sounds pretty good, cant help wondering how much difference a 1000-1200w amp would sound compared to the 600w amp. Need advice from people with experience trying different amps with the same sub.