DD Plus vs True DD Question.

Discussion in 'Blu-ray and UHD' started by Camper, Nov 24, 2007.

  1. Camper

    Camper Supporting Actor

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    david dennis
    I have a Denon reciever that is pre HDMI & pre True DD.

    I have my Toshiba A2 hooked to the reciever with an optical cable and I get good sound. It shows on my reciever as 'DTS' as I was told it would, by a knowledgeable person here before I hooked it up.

    My Question:

    Using this set-up, which will give me better sound the 'DD Plus' or the 'True DD'?
    Or does it make any difference? Is there someting lost if I chose True DD from the disc or will both sound formats sound the same in this set-up?

    Thanks to anybody who can explain this to me!
    You guys never fail to impress me with your knowledge.
     
  2. Jeff Adkins

    Jeff Adkins Screenwriter

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    Either way you are downrezzing to DTS and result *should* be about the same (except on Warner titles). I had originally thought with my A2 that DD+ would convert to DTS without any quality loss (the bitrate is the same), but the owner's manual indicates otherwise. Whether or not it's an audible difference is debatable.

    With Warner titles, if it were me, I'd select the TrueHD track since on Warner titles the DD+ bitrate is only 640kbps and the A2 is capable of 1.5m/s out of the optical cable. The TrueHD track downrezzed to 1.5m/s will sound better than upconverting DD+ 640kbps to 1.5m/s.

    I hope that wasn't too confusing!
     
  3. Camper

    Camper Supporting Actor

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    Thank you so much for that fast response.

    I will use the TrueHD for Warner titles and either for other titles.

    Thanks again!
     
  4. Nelson Au

    Nelson Au Executive Producer

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    I am using optical as well for audio. On my A35, I have found that if I select TrueHD, the audio sounds much "stronger", audio levels are higher too.

    It appears the A35 down revs to Dolby Digital, not DTS. I was trying Top Gun for the first time last night and it sounded a lot louder and better when TrueHD was selected! Same with Warner titles.
     
  5. DaViD Boulet

    DaViD Boulet Lead Actor

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    TrueHD is "lossless".

    Regular Dolby and Dolby Plus are both "lossy". Basicaly Dolby Plus is a higher-bit-rate-version of regular Dolby. But Dolby TrueHD is the only lossless-quality version and should always be used when available.
     
  6. JediFonger

    JediFonger Producer

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  7. DaViD Boulet

    DaViD Boulet Lead Actor

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    This article follows a circular argument. Without the lossless soundtrack to compare, we'll can't conclude that we wouldn't hear an improvement, despite how "good" the lossy soundtrack sounds on its own. Even the 448 kbps DD on the DVD sounds "excellent" and rates 5 stars. Does that mean that the high-bit-rate Dolby on the HD DVD doesn't sound even better? Nope... the high-bit-rate Dolby sounds better still. Why then should we assume that full lossless couldn't sound better as well?

    Folks at one time said that 720p was "good enough" and that "your eye couldn't see the difference between 720p and 1080p". Until, of course, we had 1080p to compare.

    Taking the position that lossless is "good enough" doesn't fly with me. Sure, one sound mixer says he can't hear the difference. Guess what, we had sound mixers saying that they couldn't hear the difference between the master and compressed soundtrack with the 448 kbps Dolby Digital on DVD. [​IMG] However, my ears (and many others) hear a world of difference. With lossless audio, you're not relying on someone else's ears to decide what you can and can't hear. You just get it all.

    There should be no reason on HD media why lossless can't be offered EVERY time. Period.
     
  8. Michael Reuben

    Michael Reuben Studio Mogul

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    I suggest people read the entire article (which isn't long) rather than rely on someone else's characterization.

    That being said, I agree with the advice previously given to the original poster: With the A2's trans-coding for the optical digital output, choose the lossless track, if one is available.

    M.
     
  9. DaViD Boulet

    DaViD Boulet Lead Actor

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    The writer was suggesting that we would probably not hear an improvement with lossless over the lossy encoding of Transformers based on the praise afforded to the lossy track and the perception of one sound mixer that his ears can't hear the difference between lossy Dolby at the 1500 kbps data rate and the lossless master. How did I misrepresent that?
     
  10. Mark Zimmer

    Mark Zimmer Producer

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    Do you have any analog inputs to your receiver available? You should be able to get the full effect of TrueHD without any downrezzing (though it'd be stereo) if you use those. Or does the A2 have analog outputs? I don't have one so maybe not.
     
  11. Michael Reuben

    Michael Reuben Studio Mogul

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    I saw no such suggestion by the writer, but merely a summary -- in two separate sentences -- of his two preceding paragraphs, one about the professional sound mixer, and one about Peter Bracke's review of the Transformers disc. These are two separate examples of people harping on formats instead of results. You're the one who has drawn an inference by combining the two, and I don't believe that inference is intended, especially since it's belied elsewhere in the article by statements such as the one I quoted.

    But let's assume, for the sake of argument, that your inference was justified. I think you've still grossly misrepresented the article, because it's not primarily about sound formats. It devotes as much space to video compression formats. What the article is intended to address is the way certain so-called "experts" fetishize formats and statistics as absolutes without any regard to their real-world embodiments -- as in "this format is always crap; that format is always great". IMO, the author has done a nice job of spotlighting some of the more common and insidious forms of this unfortunately widespread form of "expertise".

    One may disagree with the author, but the disagreement should at least start from an accurate assessment of what he's saying, and it's certainly not based on circular logic.

    To return to your original point, even though it's a small one within the context of the article, I don't see the author claiming Transformers couldn't sound better with a lossless track. I see him saying that the "experts" who would dismiss the disc because it lacks a lossless track have very little credibility.

    M.
     
  12. DaViD Boulet

    DaViD Boulet Lead Actor

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    I understand what you're saying.

    The author defended his position that it wasn't reasonable to dismiss the lossy track on the basis that it might be indistingiushable from the original (he uses that word).

    But...

    Since I and many others don't buy into that assumption, the argument doesn't apply. If it could indeed have sounded better in lossless (which would be consistent with other lossless tracks compared on HD media thus far), then it all depends on an individual's priorities what is reasonable when "dismissing" a given title. Is it reasonable to dismiss DVDs that aren't 16x9 anamorphic? or high-definition masters that don't use recent film-to-digital transfers? Or HD discs that don't provide lossles audio? It all depends on what's important to you and what you hear/see given you sytem and your own senses.
     
  13. Wayne_j

    Wayne_j Screenwriter

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    The A2 as well as the A3 and A30 do not have 5.1 analog outputs. The A35 does have them so Nelson would probably be better off using the analogs unless his receiver doesn't have 5.1 analog in.
     
  14. Michael Reuben

    Michael Reuben Studio Mogul

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    As for your other two examples -- anamorphic vs. non-anamorphic DVDs, and recent film-to-digital transfers vs. older (presumably) film-to-analog transfers -- they're inapplicable. In both those situations, the superiority of one method has been well-documented over a long period of time by both technical expertise and general experience. That is not the case with the new hi-def sound formats, especially at the upper end. The very fact that such analogies can be so casually drawn demonstrates the very problem to which the article is directed.

    M.
     
  15. DaViD Boulet

    DaViD Boulet Lead Actor

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    The only real difference between my examples and the situation with lossy/lossless is that those are video and this is audio. Audio is always relegated to subjectivity, because even in the best of circumstances and testing conditions, some listeners may hear differences while others do not.

    Even with the low data-rate on of lossy Dolby and DTS on DVD, there are some listeners (and audio professionals) who would hear no difference in double-blind tests. There are, of course, listeners who *would* hear differences.

    So who gets tested and who's ears do we trust? The guys trying to push a "it's good enough" agenda so we won't demand lossless audio when it's difficult to deliver?

    As long as any listener can hear the difference, then it exists. But if the guys doing the test are Dolby, and they are trying to push for Dolby Plus at a 1500 kbps data-rate for offering "transparency", do you think that they are going to invite me or the LP-loving audiophiles to take a listen to compare against the master?


    Then let the content providors prove it's transparent by providing both options on the disc. Once a track record has demonstrated transparency time and time again, so that all ears and all subject matter respond consistently, *then* we can trust that the omission of lossless audio is of no consequence.

    I'd suggest that assuming it doesn't matter, without any data to confirm, would be the more damaging conclusion if it turns out to be wrong. If I'm wrong and we get lossless anyway, then we still have transparency, just with a few more bits.
     
  16. Mark Zimmer

    Mark Zimmer Producer

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    I don't pretend to have golden ears---for instance, once corrected for volume I can seldom tell a significant difference between DD and DTS, especially as those doing the encoding have gotten better at their jobs---but there's definitely a major difference between DD+ and TrueHD. It's the rare disc that I *don't* hear a difference between them.
     
  17. Michael Reuben

    Michael Reuben Studio Mogul

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    Of course, no one in this thread (or in the article linked above) said otherwise.

    It's interesting: If you go back to the OP's question, it's whether to select DD+ or TrueHD when trans-coding either to standard DTS in a Toshiba A2. One could reasonably argue that this is truly an instance where the differences don't matter. Still, I recommended that the OP choose TrueHD if it was available. I guess that position wasn't good enough. [​IMG]

    M.
     
  18. DaViD Boulet

    DaViD Boulet Lead Actor

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    hehe. Right... since the output of that DTS transcoder is 1500 kbps DTS, as long as both Dolby tracks have at least that bit-rate to start, there's probably not much difference in the sound of the transcoded signal.

    But I'd bet that if the DD+ track on a particular disc was "low bit rate" DD+ (under 1500), that opting to transcode the TrueHD would probably improve the sound of the resultant 1500 kbps DTS signal.
     
  19. RobertR

    RobertR Lead Actor

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    It always fascinates me how the high end audio industry plays on the doubts and uncertainties of audiophiles. "well yes, the touted product failed to be indentified in this blind test, but I'll buy it anyway, because we have no absolute knowledge of anything", making it impossible to disprove any claim.
     

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