i got an MZS1204 12" mtx 300W rms sub and ive heard alot of good things about it. i had it running off my friend's 125W rms amp for awhile and it was pretty loud. but that was not even half the power the sub needed. Anyway, the other day i went and got the amp for it. the 600W rmsX2 MXA6001 MTX amp and i head alot of good things about this amp and sub and how it was so great. Well, i hooked it all up and i turn up the amp and the sub hardly moves until the gain is almost at max and they say to use the bass boost very sparingly. well, the sub is hardly hearable unless the bess boost is pretty much maxed out. I mean, i heard a review on this amp and the guy said he had it hooked to the same sub and it was sooo loud with the bass boost not even on. its a brand new amp so i doubt its that. is this just the way its supposed to be or what? the sub is in phase too. somebody please help.