shaun3000

I've seen a couple discs (Superbad comes to mind) that have both a losslessly-compressed audio track (Dolby TrueHD or DTS Master Audio) as well as an umcompressed, multi-channel PCM track. This seems awfully redundant; they should both sound the same and the PCM track takes up way more space. What's the point??

emachine12

Some receivers can't decode PCM 5.1 properly.

Some receivers can't decode dts HD Master Audio properly.

The producers want the best lossy sound possible for folks without lossless capable receivers: dts HD MA drops to dts 1.5mbs while Dolby TrueHD switches to 640kbs/448kbs DD.

For Shine A Light, all three were used:

dts HD Master Audio 5.1 with a 1.5mbs dts lossy core for the best sound.

Dolby TrueHD 5.1 with a hidden 640kbs DD lossy core for the next best sound.

PCM 2.0 Stereo for the third best sound especially for folks without surround sound equipment.

beebs

At the time this release came out, there were all sorts of options for lossless audio playback, but many of them supported only one form of lossless or another. By having all three on this disc, they covered all their bases. It was a big release at the time, a 2-disc set no less. Today, you wouldn't need so many as there are many different receivers or players that can work all three types.

-beebs

GenPion

I have a good surround sound setup that decodes all three and oddly enough I usually prefer the Uncompressed PCM. That usually tends to sound best to me - but not always. I guess it probably has to do with what it is I'm watching.

darkside

People forget what a mess Blu-ray players were the first generation and even into the second on some. Many can't decode or bitstream TrueHD or DTA MA so having the PCM is a nice option.

Drexl

Sony was using both for a transitional period, as a courtesy to those with early players/receivers that couldn't handle TrueHD. They have switched to only TrueHD now.

Josh Z

Or placebo effect.

shaun3000

Bingo

RocShemp

Or the PCM master was different. Honestly, as other's have stated before, if the same movie has Dolby TrueHD, DTS-HD Master Audio, and uncompressed PCM, they should all sound identical. If not, they are not all taken from the same master.