Sometimes bitstreaming a Blu-ray movie to a A/V receiver sounds better than BD player
Sometimes bitstreaming a Blu-ray movie to a A/V receiver sounds better compared to a Blu-ray players PCM decoding
Most of the time when a movie soundtrack has between 2.1-7.1 channels of audio the A/V receiver and Blu-ray player both can handle the movie soundtracks just fine (2.0 tracks are a different story). Under most conditions both a modern A/V receiver and modern Blu-ray player will decode the lossless audio formats PCM, DTS-HD Master audio, and Dolby TrueHD into a PCM format that is bit for bit the same as the studio master. When it comes to DTS-HD Master audio and Dolby TrueHD audio tracks both a modern A/V receiver and modern Blu-ray player are capably of unzipping the lossless digital audio data and converting them to be bit for bit the same as the PCM studio master soundtracks.
One advantage of sending DTS-HD Master audio tracks and Dolby TrueHD audio tracks in bitstream format to the A/V receiver is that many modern A/V receivers will display words like “DTS HD-Master” or “Dolby TrueHD” on the A/V receiver display. The problem with the Blu-ray player converting all audio formats to PCM is that the A/V receiver will always say PCM on the display when 2.1-7.1 audio tracks are sent (This is a minor issue for most people).
When the Blu-ray format was designed the engineers decided that the “menu beep clicks” and the profile 1.1 “picture in picture Bonus view” content would not be offered as audio bitstream feature over HDMI. Instead, the only major advantage of having the Blu-ray player convert everything to PCM is that the “menu beep clicks” and profile 1.1 “picture in picture Bonus view” content can be heard. The “menu beep click” issue and profile 1.1 “picture in picture Bonus view” feature has been a frustrating feature to use for some consumers that are new to the Blu-ray format. It is too bad that Blu-ray players are not able to mix that second audio information into the main HDMI bitstream (Of course A/V receivers than would need to be designed to decode the “menu beep clicks” and the “picture in picture” bonus content). Therefore, if one wants to hear the “menu beep clicks” or profile 1.1 “picture in picture Bonus view” content they have to have the Blu-ray player convert everything to either PCM or use the analog audio outputs on select models.
Sometimes a modern Blu-ray player or even a modern A/V receiver might need a software update to correctly handle all the advanced audio formats since the firmware incorrectly unzips the lossless soundtracks. I will use the high quality OPPO BDP-93 Blu-ray player as an example. Before the March 6th 2012 OPPO firmware update was released, OPPO BDP-93 owners when playing back 6.1 DTS-HD Master audio soundtracks would only get all 6.1 channels of audio if they bitstreamed the 6.1 DTS-HD Master audio track to a modern A/V receiver. When the OPPO BDP-93 would unzip the 6.1 DTS-HD Master audio tracks from Star Wars or the Lord of the Rings Motion Picture Trilogy it use to under the old software drop the 6th channel and decode 6.1 DTS-HD Master audio tracks as 5.1 PCM audio instead of 6.1 PCM audio. OPPO Digital INC engineers fixed this problem with a firmware update. My point is this audio quality issue did not affect consumers that used the bitstream feature to a modern A/V receiver. A/V receivers are more likely to have less audio quality issues when converting lossless soundtracks to PCM compared to Blu-ray players.
“Resolved the audio channel loss issue where DTS-HD MA 6.1 audio is decoded as 5.1 for both the analog audio outputs and the HDMI LPCM output. Sample titles include "Star Wars: The Complete Saga (BD, 2011)" and "The Lord of the Rings: The Motion Picture Trilogy (BD, 2011)". The reason is the Center Surround (CS) channel is folded into Surround channels (SR/SL) instead of Surround Back channels (SBR/SBL). This firmware decodes this 6.1 audio as 7.1 by distributing the CS channel to the SBR/SBL channels, and send out through HDMI and analog audio outputs”
On some 2.0 channel Blu-ray movie soundtracks bitstream offers much better sound quality compared to a Blu-ray players PCM HDMI output
For a while I use to always have the Blu-ray players convert all lossless audio tracks to PCM so that I could listen to profile 1.1 “picture in picture Bonus view” content plus the “menu beep clicks”. Now I always have my Blu-ray player bitstream all main audio tracks to the Pioneer A/V receiver for improved audio quality with some 2.0 soundtracks. Of course, I lose the “menu beep click” feature but that was always a minor issue for me. When I do run into a genuine profile 1.1 “picture in picture Bonus View” feature than for that Blu-ray disc I briefly change the Blu-ray player settings to mix the picture and picture audio into the PCM format.
All Blu-ray players that I have tested will not detect and decode Dolby Pro Logic matrix soundtracks located on Blu-ray discs with 2.0 audio tracks
There have been many 2.0 lossless and lossy audio tracks on Blu-ray discs that are encoded with Dolby Pro Logic information. I have ran into many 2.0 stereo audio commentary tracks and some 2.0 stereo isolated musical scores that a modern Pioneer A/V receiver will decode the matrix encoded soundtrack to Dolby Pro Logic IIx. A Blu-ray player will not detect and decode Dolby Pro Logic and Dolby Pro Logic II soundtracks from 2.0 soundtracks and instead will play the audio commentary track or isolated musical score as a left and right front stereo soundtrack. However, when the Blu-ray player bitstreams a 2.0 lossless or lossy soundtrack modern A/V receivers will detect if the soundtrack is encoded with matrix Dolby Pro Logic information.
I have seen Pioneer A/V receivers automatically switch to Dolby Pro Logic IIx sometimes, and then take two-channel audio commentaries and send the mono human dialog voice information to the center channel, and also sometimes creating a mono 7.1 surround sound information. I like it when 2.0 audio commentaries and 2.0 isolated music scores are encoded with Dolby Pro Logic and Dolby Pro Logic II information since it gives some depth to the movie soundtrack. In addition, the Pioneer Elite SC-57 has Dolby Pro Logic IIz which can activate all 9.1 channels on some future encoded 2.0 Dolby matrix soundtracks. So far, the SC-57 has only engaged Dolby Pro Logic IIx when watching some 2.0 commentary tracks.