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Originally Posted by iserum
uncompressed is better than trueHD in my opinion, on PS3 and other BDplayer uncompressed sound lot better than trueHD on my HD DVD player, TueHD on HD DVD players lowers sound so much i have to crank up volume, even DD+ sound more full on HD DVD player. most of BD movies have uncompressed audio.
Some movies have very good DD+ sound on HD DVDs, Transformers, Bourne Ultimatum have really good DD+ sound you will hardly miss uncompressed Audio or TrueHd on these movies.
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First dolby true hd is still uncommpressed audio but the bad thing that has diologue normalization here is a article from highdefdigest about it.
Dialogue Normalization – Benefit or Menace?
So let's say we pick a single movie with its soundtrack available at the same bit depth resolution in both uncompressed and lossless formats, like the 'Troy: Director's Cut'. Now we should finally have a case where playing the Blu-ray's PCM track and the HD DVD's TrueHD track back-to-back should sound instantly identical, right? Well, almost.
Now there's a new wrinkle to consider. Many Dolby audio tracks are encoded with a function called Dialnorm, which is short for Dialogue Normalization, a feature Dolby offers to set the default playback levels. The idea is to avoid having some discs start very loudly and others start very quietly when a receiver is set for the exact same volume. To do this, Dialnorm sets a default center of the soundtrack at a common average, using dialogue as a baseline. Therefore, the relative loudness of movie dialogue should be the same from one Dialnorm-encoded disc to another without a viewer needing to change the receiver volume from normal preferences.
There's been a certain level of hysteria about Dialnorm from members of the audiophile community, who misunderstand its purpose and functioning, and believe that it fundamentally alters the soundtracks encoded with it. In actuality, Dialnorm does not affect a movie soundtrack any more than raising or lowering the Volume setting on your receiver does. Contrary to common misconception, Dialnorm does not "boost" the dialogue relative to the rest of the sound mix, or in any way alter the track's dynamic range. A Dialnorm-encoded soundtrack has the exact same peaks and valleys as a soundtrack without Dialnorm; it's just that the Dialnorm track will contain an extra flag in the metadata telling the receiver to either increase or decrease its entire volume scale globally before playback, so that all movies start on the same scale. And it only does this once at the start of the movie; it does not cause fluctuations after the movie begins.
At any given volume setting on your receiver, a movie like 'Gosford Park' will deliver dialogue crisply and clearly, but the soundtrack won't get much louder, because that film is practically all dialogue. Switching to 'Jurassic Park' at the same setting, dialogue will come through just the same as it did for the last picture, until the dinosaur roars shake your house to pieces, because that movie has a lot of sound effects that are much louder relative to the dialogue. Dialnorm will not make 'Gosford Park' a house-shaking experience, or make 'Jurassic Park' any less of an auditory powerhouse. It just sets them both so that their dialogue is at the same loudness as one another.
This is relevant to our discussion because a Dolby TrueHD track encoded with Dialnorm may begin at a higher or lower starting volume than a PCM track without this feature, even though it's the same movie's soundtrack and the receiver is left at the same setting. There's a well-known principle in auditory research that has shown that listeners typically perceive a recording played back at a louder volume as better in quality than the same recording at a lower volume. That's because the louder the playback, the more pressure generated by its sound waves. At a difference of just a few decibels, the listener may not necessarily be able to tell that one track is being played louder than the other, but subtle sounds in the recording will suddenly start to vibrate their eardrums more forcefully. The result will be that the louder track seems to have more clarity, breadth, and "impact," when in fact the only real difference is that it's being played a little louder.
In order to properly compare the same soundtrack on two different audio formats, they must first be matched to the exact same volume, and this will require a sound level meter to measure precisely. Once that's been accomplished, the audible differences between an uncompressed encoding and a lossless one vanish. Being set for different starting volumes doesn't make one track better or worse in actual quality than another; they just need different volume settings on your receiver.
Does the Hardware Affect the Results?
One last factor to take into consideration: A lossless audio track is really only bit-for-bit identical to its source if it's been decoded and processed correctly. In my review of the Toshiba HD-XA2 HD DVD player, I noted a bug in its audio section that causes bass management for the multi-channel analog outputs to be applied inaccurately when the "Digital Out SPDIF" control is set for Bitstream rather than PCM. That player also seems to apply Dynamic Range Compression whether you want it or not unless all speakers are set to a Small size. Without the required workaround settings (SPDIF at "PCM" and all speakers Small) all movie soundtracks seem to be lacking bass over those audio connections.
If a viewer weren't aware of this problem, a first inclination might be to assume that the Dolby Digital Plus and Dolby TrueHD audio formats used on HD DVD were poor quality. However, this is actually just a defect in one specific player, and not at all indicative of the audio formats themselves.
Similarly, although Fox Home Entertainment prefers to use DTS-HD Master Audio on its Blu-ray releases, at the present time there isn't much hardware that can decode the full lossless extension to the codec. Most currently-available Blu-ray disc players and A/V receivers instead extract the lossy DTS "core," so the majority of listeners aren't hearing the format to its fullest potential. That's not a knock against Master Audio, but rather a limitation imposed by the playback hardware.
What It Boils Down To
The number of new audio formats on Blu-ray and HD DVD have caused a great deal of consumer confusion, especially with three separate formats (PCM, Dolby TrueHD, and DTS-HD Master Audio) all designed to accomplish the exact same goal -- a perfect replication of the movie's audio master. Apprehensions about lossless compression being inferior to an uncompressed version of the same soundtrack are not borne out by the facts. One methodology may have technical advantages over the other in terms of space savings, but the end result is the same whether the disc you buy has an uncompressed soundtrack or a lossless one. They're both equally good, so sit back and enjoy.