I noticed that all blu ray discs have different sound formats. I have a thx reciever and 5.1 surround sound klipsch reference speakers. I want the best sound quality so which format do i look for in the discs? There are so many formats like Dolby Tru HD or DTS-ES. But are they all the same in sound. Please reccomend which format to look for, to get best perfomance of my speakers.Thanks