Originally Posted by usxplong
Thanks Bob and AbMagFab.
I resolved the issue of Bitstream & PCM last night. My BD55 player has an optio to enhance the dialog. That caused the front channel to receive higher volume. I turned that option off and got exact same sound from Bitstream & PCM.
Thanks again for all your help.
Great! There are so many options to check in cases like this, it can really be confusing.
During Beta testing for the Oppo Blu-Ray player I've done extensive comparison of the Oppo sending Bitstream to the D2v vs. the Oppo decoding to LPCM vs. the PS3 decoding to LPCM.
Whatever you might think of the PS3 as a player, one thing that's known is that it puts out proper levels and correctly decodes the vast majority of the lossless tracks.
I compared levels, and I also compared sound quality. All 3 ways are identical.
With three exceptions:
(1) The PS3 can be set to down-mix 7.1 tracks to 5.1. The D2v will do that as well of course. In my 5.1 speaker setup I found the sound quality was much improved for 7.1 tracks if I set the PS3 to output the full 7.1 LPCM to the D2v and let the D2v do the down-mix to 5.1 speakers for me. (For the original D2 you have no choice but to let the PS3 do the down-mix to 5.1 for such tracks.) NOTE: The Oppo always sends 7.1 to the D2v for such tracks, and 5.1 to the D2 -- so there's no setting you can get wrong here.
(2) The Oppo and the PS3 have DTS-HD MA "Essentials" decoders -- a limitation that only affects their decoding of traditional, lossy DTS tracks. This means they don't decode matrixed rear speaker audio for lossy DTS-ES tracks as found on some SD-DVDs. For either player, select Bitstream output of the DTS-ES track and the D2v will do this correctly. (Although the PS3 can't output Bitstream for lossless tracks, it CAN do so for lossy tracks.)
(3) The D2v does not decode the special embedded coding of HDCD audio discs. It plays them just as if they were regular CDs (HDCD coding is backward compatible with CD players). The Oppo DOES decode these discs, raising the 16-bit LPCM coming off the disc to 20-bit audio embedded in 24-bit audio to send to the D2v -- raising the dynamic range at the expense of increasing the noise floor. So when playing HDCD audio discs, use HDMI LPCM output from the Oppo to get the full dynamic range of these stereo recordings.
Also note that DTS is once again screwing up the Blu-Ray world with unnecessary complexity in DTS-HD MA. There are some new discs out there which have 5.1 DTS-HD MA tracks that are mistakenly getting decoded as 6.1 (or 7.1) because the CORE lossy DTS track embedded in there is DTS ES Matrix. Just as with the last case of this, where studios started using the "alternate speaker presentation" for surround speakers, there are DTS-HD MA decoders out there which are getting tripped up by this. And just as with that case, it is not patently obvious what the correct answer should be. So for discs screwing around with this, there will be some differences in decoding until the various decoders get their act together.
Honestly, when the AV revolution comes, DTS should be first up against the wall. /rant