A little help for a noob regarding DTS, DTS HD, and downmixing

[neelshiv]

Hey guys. My parents have a bit of a home theater setup in their basement (most of it came with the house), and they received a blu ray player as a gift for last christmas. Up until about a month ago, the only dvd's that they had were The Dark Knight and Transformers, but they then bought Marley and Me. They called me and asked me why the sound wasn't working, but I was over 500 miles away, and couldn't really help.

I just got home a few days ago, and tried it out. I found that the non-english tracks were working, and I assumed that the disc was defective. They then bought Slumdog Millionaire, and it had the same problem. It was then that I put one and one together (or perhaps some more complex equation, like two and two) and realized that audio tracks labeled "DTS HD" were not working. Batman and Transformers did not have these, which explained why they worked.

I then looked into the blu ray players settings (a sony BDP-BX1), and messed around a bit. I know relatively little, but there were also very few options for most of the dialogs, so I worked something out.

Our receiver is an older yamaha rx-v992, and it is capable of dolby digital. The player is connected to it via an optical cable, and it is connected to the projector via an hdmi cable.
Our player has the options of "downmix pcm" and "dolby digital" for dolby digital output, and it is set to dolby digital. It sounds great. When watching a movie, the player displays "Dlby Digital" on the front and everything is in order.

The DTS output setting used to be DTS, but it is now set to Downmix PCM. We now get sound when watching these movies, but the receiver displays "Pro Logic", with the letters text "PCM Digital" under that. Sound certainly comes out of all speakers, but I don't really know much about whether or not it is the same rear speaker sound that DTS output would get.

Another setting that may be relevant is the "Downmix" field, which has the options Dolby Surround (selected) and Normal.

*Does this seem like the best setup we can achieve for DTS audio tracks? How does it differ from an actual DTS output? I believe somebody has told me it is lossy, but that is not our greatest concern. We mostly care about getting actual 5.1 sound (which the previous owners had not set up correctly for the several years they lived here).


Sorry for the lengthy post. It really boils down to one question (precluded by an asterisk), but I felt that it required a bit of setup and back story.