Well, I have a yamaha rx-v2500 that has THX select and utilizes the THX surround EX, but my high expectations were brought down after listening. The receiver is great and its sound to me is awesome, but when i select THX, the volume and tones seem to decrease and does not neccessarily have that great of a punch to it as oppose to it being in standard surround. I just got this receiver so im still playing with it to pull the best out of it, but I see myself not wanting to use THX. Could i be doing something wrong in the settings? According to the manual, THX has its own settings that it uses. I calibrated using yamaha's YPAO and it did a pretty good job of doing so. Has your THX experience been likewise? another, is THX best used only on dvd titles that have been THX certified? Is THX surround ex the same as 6.1, just in addition to the additional center rear?