petetherock Posted October 20, 2008 Posted October 20, 2008 I felt this was an exciting enough finding to warrant a new thread It has been my uninformed opinion that there should be a difference due to different chipsets, jitter etc, but this is quite an interesting find. Just read this on another forum, where the claims of bitstream signals sounding better than the internal decoding are due to improper LPCM signals: http://www.avforums.com/forums/audio-proce...tml#post7940326 QUOTE I'll add another complication. A manufacturer (who shall remain un-named) informed me that:"to date the only successful implementation of p2 is the PS3. Even machines as recently launched as the Panny DMP-BD-50 output LPCM but only derived from the core not the DTS HD / Dolby Tru HD - All the BD player manufacturers are covering this up very well. The BD 50 and a couple of others are going to be able to correct this with a (already promised) firmware update and most future Profile 2 machines from all manufacturers will correct this and output full HD audio. so... in summary ... all of the people comparing LPCM output via HDMI / vs Bitstream into something like an xxxxx (name deleted but basically all AVRs - Russell) are actually hearing the difference between the core soundtrack and the HD soundtrack." It would seem that regardless of the technicalities, the situation is the normal AV industry SNAFU that almost renders all such technical discussions slightly moot, unless you are really sure what you are listening to. Russell
petetherock Posted October 20, 2008 Author Posted October 20, 2008 If I may add a quote from SDL from another thread: http://www.dtvforum.info/index.php?showtop...p;#entry1187496 Interesting if true, would mean that yes the PS3 and the Pana sound different, but in fact the PS3 is in fact theoretically a better reproduction when comparing PCM. Not sure that would explain, if it is the case though, how some believe the PS3 LPCM is not as good as Bitstream on the Pana - but maybe I'm misunderstanding something in the quote?Anyhow, the I hadn't posted in this thread as it seemed to go along the same lines as the other one. But to me it still appears there are two seperate agendas and people with different mindsets arguing about something where no compromise is really possible. Group A, those that have done some tests, found that in their opinion that Machine A is better than Machine B, are happy with their results, happy with what they decided to do based on those results, and were happy to share their views. These views were never intended to be scientific, they were not done to make a definitive statement, and those results could be due to some factors they didn't consider but they don't believe so and as stated are happy with the outcome. I can understand this, my system gives me the best sound in my house and when I upgrade it will give better sound. I don't need double blind tests to tell me there are better systems and some not so good. There is a point when we all need to make choices and then sit back and enjoy. I mean how many of you really did double blind testing on each and every piece of equipment in your setup? And how many were actually in their setup and not in some demo room of the retailer? Group B, those that want to dig deeper, find the reason why the theory may or may not hold up. Find what is being down to the sound generated and why. Look for the issue along the chain and try to eliminate all potential causes to narrow it down. I too can understand this group being an Engineer by qualification. I have done a lot of systematic testing and root cause analysis to find issues with major equipment failures. This process approach is something I do as second nature and get frustrated at times working with people that want to focus on just what they perceive to be the issue as experience has found that those people who think they have experience and can single in on the issue often spend more time frigging around and finding they are wrong. Anyway, as I say I can also understand these people. The problem is that the two groups of people are not going to reach compromise. One group cannot ask another to accept their views if the other group is scientific in nature and looking to prove or disprove the whole issue, and that second grouop cannot ask the first to do tests they have no interest in doing as they have heard the results, they know which they prefer, and so no reason to have to prove beyond reasonable doubt to another group what they already know to be true. So perhaps one thread should be left purely for scientific experiment with people ready to receive grilling and ready to give it, but those doing the grilling understand it isn't acceptable in another thread where people just want to discuss the findings of their latest gtg or what a new piece of equipment sounds like in their system as compared to another without fear of being asked to do a double blind test at 1 atmosphere and at sea level (up to +40m). There should be room for both types of discussion with people being able to enter and leave either without fear of reprisal. Anyway just my 0.02c worth. and just in case anyone wonders my PS3 is my best sound ing Blu-Ray player - well only because I haven't heard another one yet and am not too bothered right now.
petetherock Posted October 20, 2008 Author Posted October 20, 2008 And one from Macca: http://www.dtvforum.info/index.php?showtop...p;#entry1187567 Thanks for the link.They seem to suggest that the PS3 is decoding the full HD audio(so this has no direct impact on the tests performed in the thread). But they also seem to be under the impression that all profile 2 players are supposed to decode all the HD audio formats............I'm pretty sure that profile 2 does not mandate any decoding ability other than those in the standard BD spec (ie PCM, DD and DTS) So are they assuming that all profile 2 players should support HD audio decoding, because they don't need to to be profile 2 compliant. It is unnerving that they have found some players that specifically state they support HD audio decoding yet they actually don't ie the BD50(maybe there is some fine print in the manual that states "subject to firmware update"). I wonder how many on this list should be changed I am yet to do any more testing but am interested to try out I Am Legend. Would be interesting if I was able to capture a waveform difference with this title..........I wonder if it has something to do with that TrueHD DRC bug rearing its ugly head in the background somewhere that we can't adjust for(or the DRC control of the PS3 is not operating correctly).......dunno. cheers
hakka69 Posted October 20, 2008 Posted October 20, 2008 First i've heard of profile 2 having anything to do with HD audio decoding. DTS-HDHR/MA are the only HD codecs that use the core + extension setup. Makes me wonder about the 'anonymous' source of this information. Hakka.
petetherock Posted October 20, 2008 Author Posted October 20, 2008 I don't think its the Profile bit... Just that it would be a scandal if the latest players which claim internal decoding actually don't do it. I have to try Labyrinth on my XE1 and borrow a Blu Ray to try on my PS 3....
hakka69 Posted October 20, 2008 Posted October 20, 2008 from that same thread: ============ Quote: Originally Posted by welwynnick Without revealing your source, is there anything you can add to show how reliable you think this is? Stunned, Nick Absolutely nailed on unfortunately. I have no reason to disbelieve them, simply because they (like so many) have no BR spinner of their own and thus, no real vested interest. I can't reveal the manufacturer, but they discovered this info whilst searching for a player that could reliably output all soundtrack formats in both LPCM & Bitstream for development of their own products. To their surprise, the PS3 ended up being the only reliable one, although others have since joined it, where firmware updates have allowed. If you combine this with the fact that some AVRs only decode the core soundtrack from the full HD bitstream (even if they are displaying DD-HD/DTS-MA up in lights), the levels of uncertainty multiply to levels where it seems a significant portion of the population has never heard a full HD soundtrack, in spite of having invested significant sums to do so. It certainly makes interesting reading if you pick up a few back issues of the popular press. Russell ============ Since when does the PS3 output HD audio over bitstream?? Maybe I'm missing something here. I need to do more reading on the BD-50 but are they saying it bitsreams HD audio but internally decodes legacy audio?? If so its basically the BD-30 with a higher price tag.
bbar Posted October 20, 2008 Posted October 20, 2008 (edited) First i've heard of profile 2 having anything to do with HD audio decoding.DTS-HDHR/MA are the only HD codecs that use the core + extension setup. Makes me wonder about the 'anonymous' source of this information. Hakka. I agree and from what I can find the Panny BD50 does decode TrueHD and DTS-HD MA. It does not do HR but there is little if any content in this format. Also, agree that TrueHD is not core based as with DTS... So, not convinced about lack of Panny 50 ability to decode. Agree;however not many can decode MA right now. As far as I know the BD50, BD55, S550, Denon and Marantz players are the only ones that can fully decode right now and the Pio will have the ability early next year . Talk about a conspiracy theory - Some player manufacturers say they are decoding MA and TRueHD but are not; and some AVR's that display DTS HD MA and say they decode DTS HD MA are not really decoding the extensions just the core?? Sorry, but have a hard time believing this. Agree however that some players have in the past suggested DTS HD decoding that was limited to core; but they never specifically stated DTS HD MA. Bryan Edited October 20, 2008 by bbar
momaw Posted October 20, 2008 Posted October 20, 2008 I agree and from what I can find the Panny BD50 does decode TrueHD and DTS-HD MA. It does not do HR but there is little if any content in this format. Also, agree that TrueHD is not core based as with DTS... So, not convinced about lack of Panny 50 ability to decode.Agree;however not many can decode MA right now. As far as I know the BD50, BD55, S550, Denon and Marantz players are the only ones that can fully decode right now and the Pio will have the ability early next year . Talk about a conspiracy theory - Some player manufacturers say they are decoding MA and TRueHD but are not; and some AVR's that display DTS HD MA and say they decode DTS HD MA are not really decoding the extensions just the core?? Sorry, but have a hard time believing this. Agree however that some players have in the past suggested DTS HD decoding that was limited to core; but they never specifically stated DTS HD MA. Bryan I'm with you Bryan. Early adoptors scream red and blue at the littlest imprfections (just look at the bagging the obstesibly perfect New Lines transfers receive due to a belief they are over processed). Given how many have started off with PS3's (the one player supposedly doing the right thing) and now say they get better sound with other equipment, I find this claim quite hard to believe. Ignoring the punters, Dolby and DTS would be up in arms if manufacturers were passing core of as HD. Now call me paranoid, but with PS3 market share rapidly dimishing as people dump it for standalones or don't buy one in the first place, and given how hard Sony Computer Entertainment fought to get that market share, it wouldn't surprise me if this was a little bit of the old hydra.
petetherock Posted October 20, 2008 Author Posted October 20, 2008 I tend to remain a little skeptical, even if this Russ chap is well regarded in those circles. But bottom line, I am happy with my PS 3, and unless there is a massive improvement, I will keep it for some time to come. Gotta save a few pennies this year....
cwt Posted October 20, 2008 Posted October 20, 2008 Talk about a conspiracy theory - Some player manufacturers say they are decoding MA and TRueHD but are not; and some AVR's that display DTS HD MA and say they decode DTS HD MA are not really decoding the extensions just the core?? Sorry, but have a hard time believing this. Agree however that some players have in the past suggested DTS HD decoding that was limited to core; but they never specifically stated DTS HD MA.Bryan The one about core decoding in avr's of dts hdma is a beauty Bryan .People must be hearing things from the B/Surrounds when a 7.1 ma track is replaced by the 5.1 core And even if it was say an alternative 6.1 dts-es track it would be flagged as such unless the disc manufacturers were in on it too As Hakka says they dont seem able to discern that true hd is based on mlp lossless and has no core - seperate track required..
peterjcat Posted October 20, 2008 Posted October 20, 2008 This can ONLY be about DTS-HD, where it's true that (1) very few players can internally decode it to LPCM, and (2) it has a perfectly good DTS core that they can decode instead. Most players can decode TrueHD to LPCM and have done so since the beginning. As has been said there's no core as such to TrueHD (though on Blu-ray (not HD DVD) there is a mandatory interleaved AC3 track).
bbar Posted October 20, 2008 Posted October 20, 2008 The one about core decoding in avr's of dts hdma is a beauty Bryan .People must be hearing things from the B/Surrounds when a 7.1 ma track is replaced by the 5.1 core And even if it was say an alternative 6.1 dts-es track it would be flagged as such unless the disc manufacturers were in on it too As Hakka says they dont seem able to discern that true hd is based on mlp lossless and has no core - seperate track required.. Agree; but I will go as far as to say that some CE's have made it difficult to understand what they actually decode with respect to DTS HD. Expecially on previous players. Even Pioneer with the 05fd and 51FD stated it would decode MA on their WEB page; but do not clearly state that it requires a future firmware update. Samsung did the dirty on future firmware with some of its players also. It is my understanding that the use of DTS HD refers to both HR and MA whilst some CE's use a different definition. I guess I would go as far as they didn't go out of their way to highlight things like number of analogue ports as they would state it decoded to 7.1; but did not clearly articulate that it did so with LPCM over HDMI and downmixed to 5.1 over the analogues; or that it decoded HR and not MA or vice versa (not big deal with HR as not really used I believe) There is clearly a buyer beware with Blu ray players at this point. Bryan
tb1231503560936 Posted October 20, 2008 Posted October 20, 2008 Ok, so you guys have just confused the daylights out of me! a simple question then hopefully if what is written above is true....... I have a Pioneer LX70a Bluray player and a Pioneer LX60 AVR. If I play a copy of Ironman that has a TrueHD soundtrack, am I or am I not listening to an HD track? cheers
Shonky* Posted October 20, 2008 Posted October 20, 2008 Yes you are if that's what you selected to either decode on the player or bitstream to the AVR. The issue here is DTS MA specifically, since the player can take the lower quality lossy "core" and decode that instead of the full high quality lossless track. TrueHD is TrueHD. So if the player says that on the OSD or better yet (in terms of confirmation) you bitstream it and the receiver says "Dolby TrueHD" you can be assured.
Davidian Posted October 21, 2008 Posted October 21, 2008 I have a similar question to tb123 (and are equally confused); I have a PS3 and a Yamaha RX-V663 - am I better to have my PS3 output bitstream or pcm to the amp (using HDMI)?
MACCA350 Posted October 21, 2008 Posted October 21, 2008 TrueHD is TrueHD. So if the player says that on the OSD or better yet (in terms of confirmation) you bitstream it and the receiver says "Dolby TrueHD" you can be assured.There may still be an issue with TrueHD as IIRC BD players will output the DD track over SPDIF if the TrueHD track is selected, so what was mentioned in that thread suggests that some may show TrueHD selected in the menu while actually decoding the DD track for HDMI PCM output also.If that is what is happening with the HD audio tracks on some players there is a real problem because it is clear misrepresentation, and I'm sure(as Mo mentioned) that Dolby and DTS would have been aware of the issue and not licensed the implementation. Remember these formats(DD+, TrueHD, DTS-HDHR/MA) are licensed products which means that they must pass Dolby's and DTS's strict guidelines before they are able to use them in the public arena(both physically and written). I know that at least Dolby test every implementation of their codecs to confirm compliance before granting licences, I'm pretty sure this is the case with DTS also(but haven't seen it confirmed or stated by DTS) cheers
petetherock Posted October 21, 2008 Author Posted October 21, 2008 (edited) The PS 3 does NOT output lossless sound formats via bitstream. There is no such choice for it. Cheers I have a similar question to tb123 (and are equally confused); I have a PS3 and a Yamaha RX-V663 - am I better to have my PS3 output bitstream or pcm to the amp (using HDMI)? Edited October 21, 2008 by petetherock
Shonky* Posted October 21, 2008 Posted October 21, 2008 I have a similar question to tb123 (and are equally confused); I have a PS3 and a Yamaha RX-V663 - am I better to have my PS3 output bitstream or pcm to the amp (using HDMI)? A PS3 cannot bitstream the high def audio tracks so you don't have a choice.
jutta Posted October 21, 2008 Posted October 21, 2008 I'm assuming that bitstreaming the DTS HD MA tracking avoids the potential decoding issue. Would this be a correct assumption???? From what I have read from the above posts it seems to relate to internal decoding by the player, true? Or have I not fully grasped the concept yet?
Shonky* Posted October 21, 2008 Posted October 21, 2008 (edited) I'm assuming that bitstreaming the DTS HD MA tracking avoids the potential decoding issue. Would this be a correct assumption????From what I have read from the above posts it seems to relate to internal decoding by the player, true? Or have I not fully grasped the concept yet? Simply: yes. Then your AVR reports what it's seeing so you know for sure it's decoding DTS HD MA Edited October 21, 2008 by Shonky*
Davidian Posted October 21, 2008 Posted October 21, 2008 A PS3 cannot bitstream the high def audio tracks so you don't have a choice. Awesome... /shakes head in disappointment at PS3 It's currently set to PCM, but the other night I was watching Iron Man and the Yammy seemed to be stuck in '7ch Enhanced' mode, normally it would display 'PCM'... anyway, I'm digressing from the topic at hand, so I'll leave it there!
hakka69 Posted October 21, 2008 Posted October 21, 2008 There may still be an issue with TrueHD as IIRC BD players will output the DD track over SPDIF if the TrueHD track is selected, so what was mentioned in that thread suggests that some may show TrueHD selected in the menu while actually decoding the DD track for HDMI PCM output also.cheers I dont think it will output the DD track on the SPDIF, it will re-encode the TrueHD track on the fly as DD. Earlier players (XA-1/360) were outputting as DTS on the SPDIF when there was no DTS track present on the disc. Not all players are the same but if the TrueHD is selected in the disc menu and is being output to HDMI and analog 5.1, to output the DD track to the SPDIF woudl require another audio decoder. http://www.dolby.com/consumer/technology/t...eHD_avrs_2.html from that link: ================ S/PDIF Connection If your A/V receiver or processor has neither multichannel analog or digital inputs, but is equipped with 5.1-channel Dolby® Digital decoding and playback, you will still be able to enjoy 5.1-channel performance from next-generation optical players. Included within 7.1-channel multichannel Dolby Digital Plus and Dolby TrueHD streams is a core 5.1 mix prepared by the content maker that is used when the player is set for 5.1-channel mode. After playback audio signals have been mixed in the player, the PCM signal can be encoded to a Dolby Digital signal and output from the player via S/PDIF (optical or coaxial) to your connected Dolby Digital A/V receiver or processor. In many instances, the audio quality you will experience from this connection may be better than what you would experience during playback of standard-definition DVD-Video discs, especially if the native signal on the disc is Dolby TrueHD or high-bit-rate Dolby Digital Plus. This is a direct result of a higher-quality source signal feeding a Dolby Digital encoder running at 640 kbps—higher than the maximum bit rate on DVD-Video. Figure 4 Connection via S/PDIF Because Dolby Digital encoding support is optional in HD players, you will need to look for a next-generation player equipped with a S/PDIF output and built-in Dolby Digital 5.1-channel encoding technology. ================== They mention a core 5.1 mix contained in TrueHD and DD+ tracks, if you read the Truehd/DD+ tech papers (page 3 and 4)it goes into a lot more detail on how the 5.1 mix is contained in the 7.1 mix, not really a 'core' like the DTS implementation, but a HD track with less rear channels. A 7.1 track actually has 9.1 channels encoded on the disc. http://www.dolby.com/uploadedFiles/English..._whitepaper.pdf Hakka.
cwt Posted October 21, 2008 Posted October 21, 2008 I know that at least Dolby test every implementation of their codecs to confirm compliance before granting licences, I'm pretty sure this is the case with DTS also(but haven't seen it confirmed or stated by DTS)cheers Have no fear on the dts front Macca ; dts has cirrus logic jumping through all the hoops to gain accreditation for its cs40997 decoding chips . One reason the cary 11a is overdue . IIRC ;Read the other day that if the dts engineers fail a encoding step then the process starts all over again ; not as easy as dolby true hd unfortunately The long delay between the TI lossless decoders for the early avr's and the trouble cirrus logic is having for its chips does give pause ; quite a few ce's waiting for these chips. Will certainly be bitstreaming when I can do so
MACCA350 Posted October 21, 2008 Posted October 21, 2008 I dont think it will output the DD track on the SPDIF, it will re-encode the TrueHD track on the fly as DD. Earlier players (XA-1/360) were outputting as DTS on the SPDIF when there was no DTS track present on the disc. Not all players are the same but if the TrueHD is selected in the disc menu and is being output to HDMI and analog 5.1, to output the DD track to the SPDIF woudl require another audio decoder.Not really because it would be only decoding one stream, the DD track would be simply routed to the SPDIF output(this is explained in the whitepaper you linked). Whether the players are actually doing this while playing a TrueHD track I'm not sure(I've heard others mention it though)TrueHD does not contain a "core" 5.1 DD mix. "7.1-channel program is delivered in three separate components: a two-channel mix, the 3.1- channel extension A, and the two-channel extension B" "Dolby Digital Plus was designed to employ an altogether new technique to address the downmix compatibility issue, and is the only perceptual coder thus far to do so. In its “core plus extension” structure, the Dolby Digital Plus core is a complete 5.1-channel mix; the extension contains the new channels, plus any channels that have been modified between the 5.1 and 7.1 renditions." That whitepaper is quite a good one and I have referenced over the years cheers
AGP Posted October 21, 2008 Posted October 21, 2008 Now call me paranoid, but with PS3 market share rapidly dimishing as people dump it for standalones or don't buy one in the first place, and given how hard Sony Computer Entertainment fought to get that market share, it wouldn't surprise me if this was a little bit of the old hydra. Hi momaw I agree with you here I am selling my PS3 for a dedicated player. If I had a choice between players when I made the purchase 10 months ago it would have of been a standalone.
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