Ok, I have browsed several speaker lines that have THX certification. The M&K S150 speakers are -2 db at 77Hz and the Atlantic Technology 450 system mains are -3db at 80Hz. Now, I am not buying a THX system, but the speakers I will be using (M&K S-125's) have the same 3db point as the S-150's...77Hz. Now, it seems the THX speakers have a fairly high -3db point for being crossed over at 80Hz (per THX processor spec). The only thing I can come up with is that THX processors must have a very high order crossover to facilitate the transition from satellite to sub over such a small frequency range. Now, if I will not be using a THX processor (I will be using the outlaw 950) , then will I have problems crossing over at 80Hz, or should I consider moving up to 100 Hz? I'd try for myself but none of the system is purchased and this is basically just something that piqued my curiosity. Thanks.