digitalfreaknyc said:

I complained about this in blu-ray.com when the blu-ray came out and several people commented that the DTS 768 equals the PCM. I didn't understand why but they explained it.

48kHz = 48,000 samples per second.

Each sample is 16 bits, therefore mono PCM is 1 x 16 x 48,000 = 768,000 bits per second = 768kbps.

However, the specs above say that it is encoded as dual mono (same track in left and right channels) and uses 24 bit samples. Uncompressed this would be 2 x 24 x 48000 = 2304kbps, so 768kbps represents a track that has been compressed to a third of its original size.