Originally Posted by smfins
i wanted to be able to experience the two newest formats, DTS master HD and DD True HD My questions are, whats the advantage these have over the Dolby Digital EX and the previous DTS?
There is no such thing as "DD True HD". DD and TrueHD are two different Dolby codecs.
DTS-HD MA and Dolby TrueHD are lossless packing technologies, like zipping a computer file. They pack the audio data more efficiently, to take up less storage space on the disc, without throwing away any of the data. This allows you to have a bit-for-bit identical copy of the original studio master that was used for encoding.
DD (Dolby Digital) and DTS are lossy compression technologies, like MP3 or AAC. They use psychoacoustics in an attempt to drastically reduce the amount of data while minimizing the impact on sound quality.
EX is matrix encoding and decoding technology. An EX encoder is used to fold a 3rd surround channel (the surround-back channel) into a discrete 5.1 soundtrack by mixing it equally in the left & right surround channels. Matrixing in an additional surround channel doesn't make the soundtrack 6.1, just makes it 5.1 EX.
Upon playback, the EX decoder in your receiver will extract the surround-back channel and send it to the speakers behind you, while the L/R surround channels will be sent to the speakers at your sides. This allows you to have stable rear-vs-side directionality in the surround field. However, if you have a 5.1-speaker layout, then the surround-back info will phantom image behind you (backwards compatibility).