how do i know that thx sound between dolby becouse when i take my thx speakers to my old dolby reciever(that had fix crossover to 80hz also had a low cut filter)doesnt make any different....(only a little bit different)please tell me how...to compare between them..they said that thx sound is likely director intend....is that so ....how about my old receiver..(when fix)they had sound almost like thx to...