1) if HD audio, or any audio, is "decoded" you have PCM already. I am a little confused by your confusion.
2) Your DD receiver will work with EITHER pre-decoded audio, or bitstreamed audio, as long as its not of the lossless variety. (Well, optical can handle lossless 2.0 PCM).
TrueHD comes with accompanying legacy DD tracks. The bitrate is improved upon DVD, IIRC, something like 640 kbs vs 448 kbs. This is NOT hi def audio, so to speak. Even your DTS track on a DVD is of higher bitrate.
DTS-MA comprises of concurrent multiple bitstreams. I believe the ES version on DVD works the same way, essentially as an extension stream.
Its more complex. On one hand, it takes more space than TrueHD on its own. OTOH, it takes less space than TrueHD and the accompanying DD track. Since they are all accompanied, MA is more efficient.
The least efficient in terms of space are the uncompressed PCM tracks, because, well, they are uncompressed.
IN A NUTSHELL, you will get audio just fine. It just won't be high-def, but improved "legacy" or "core" tracks. I think DTS-MA core (1st of 2 bitstreams) might get you as high as 1.5 mps. Which would be 3x the bitrate of your old Dolby tracks.
However, these bitrates are variable, and for good reason.
Looking at getting the Sony BDP-S350 which I understand decodes HD audio but simply outputs it via optical instead of PCM as the more expensive -S550 (and similar models) does. Am I correct that even if I have a plain-Jane Doly Digital receiver it will work with pre-decoded HD audio tracks coming off the Blu-Ray?
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