Uncompressed Audio...

Anyone notice how Blu rays released with Uncompressed 5.1 audio are very rare at this point?

Sony released all their Blus with Uncompressed audio and then they switched to TrueHD.

Warner, after they gave us a bunch of 5.1 DD+ mixes, switched to PCM for Harry Potter, The Departed, 300, Troy, and probably a few others, but now only TrueHD.

BVHE/Disney did the same thing...lots of Uncompressed tracks (POTC Trilogy, Enemy of the State, Con Air, The Rock, etc) and now offer DTS-HD MA (No Country... re-release, Miracle at St. Anna, Wall-E)

Anyone else here actually prefer PCM tracks to TrueHD or DTS-HD MA?

I've heard some darn good tracks from all different audio codecs, but I have to saw, the PCM tracks I heard from 300 and Enemy of the State were superb.

I also realize that they are much larger and take up so much more room on the discs, but is there actually a "sound" benefit to having PCM over the other two?

And I have another question that I'm not too clear on, maybe someone can clear it up for me...if Dolby TrueHD and DTS HD-MA are touted as lossless and that they should be identical to each other...then why the difference in bit rates? Why even have two competing codecs that are supposedly the same? Are they actually the same?

Most TrueHD tracks hover around 1.5 kbps, and I understand some are higher, but most of the DTS-HD MA films I've watched are usually much higher, almost all over 3 kbps, sometimes topping out at 5 or 6, depending on the title.

The reason for my asking is because of releases like No Country for Old Men re-release going to DTS-HD MA. I read a review of the new collector's edition that said the audio on the PCM version was a tad better. Same goes for Casino Royale CE (TrueHD) vs. the original releae (PCM).

Am I making too much of this?

-Dave

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I also realize that they are much larger and take up so much more room on the discs, but is there actually a "sound" benefit to having PCM over the other two?

Technically UC 5.1, DTS HD MA and Dolby True HD should sound identical provided they are originated from the same uncompressed source. However keep in mind that DTS HD MA and Dolby TrueHD are only 'lossless' at their ideal bit-rate (which I believe is around 18Mbps for both). Some releases may use less that the ideal bit-rates meaning the the audio quality may vary from 'lossless' to 'near lossless' depending on how well the audio data compresses.

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The reason for my asking is because of releases like No Country for Old Men re-release going to DTS-HD MA. I read a review of the new collector's edition that said the audio on the PCM version was a tad better. Same goes for Casino Royale CE (TrueHD) vs. the original releae (PCM).

These comparisons are rarely accurate. There have been experiments where people have heard differences in the same audio recording played twice just because they were told there was a difference. The only way to realistically compare the quality of the audio codec is to compare the difference in the waveform of the compressed audio to the uncompressed source it was made from.

If there is in fact a noticeable difference in the audio of the two releases it might have more to do with differences in the mastering of the audio in both releases. There is also the possibility that the equipment the reviewer is listening to the audio on may not support proper decoding of the high-def audio. For instance, when comparing an uncompressed release to a DTS HD MA release on a system that does not support true DTS HD MA decoding you are actually comparing uncompressed audio to traditional DTS audio compression (the DTS HD MA's 'core' used for compatibility) which is lossy.

So in essence that is the advantage to uncompressed 5.1 over 'lossless' compression. Almost all Blu-ray players will output uncompressed 5.1 in full quality, however you need a player that supports true DTS HD MA and/or Dolby TrueHD decoding to get the benefit of 'lossless' audio on those releases.

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I also realize that they are much larger and take up so much more room on the discs, but is there actually a "sound" benefit to having PCM over the other two?

No, if your player/receiver supports DTS HD MA or Dolby TrueHD. Yes, if it doesn't support it. This of course assumes that the DTS HD MA/Dolby TrueHD are not encoded at low bit-rates.

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[Post edited by the_dvd_chef on Apr 16, 2009 - CDT 11:52 PM]

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Am I making too much of this?

--Dave

Yes.

DVD Chef gave a good and thorough explanation. If done correctly, there should be no difference in the sound quality of TrueHD, DTS Master Audio, and uncompressed PCM.

The reason most studios are going to TrueHD or DTS-MA is that they take up much less space than uncompressed PCM tracks. Space counts, even on a Blu-ray disc.

John

Sorry John,

I Beg to differ. What is quite pathetic, is that even the movies/features with Uncompressed PCM, make little to no difference on the whole amount of the disk title amount. I have found from disk to disk varies very little. There is still on average 5 to 6 gigs of "free" space still left over. Honestly, studios are too lazy to spend the R&D time to render the PCM file to the final master. At this point ot boils down to time constraints, cost and impatience that is ruining it for the customer. Dolby and DTS have alike different methods of sound manipulation/compression, and are competing for that almight US $. With Blu-Ray, space is a non-issue. When you Consider that 95% of the Blu material I have "looked at" has never exceeded 45 gigs... Advertising and Money making dollars...

BTW, have you noticed any cool DD or DTS intros at the Cinema Lately? It's been quite some time...

on top of everything, most people can't hear the differences between theatrical mixes, dolby digital on dvd, dolby digital plus, dolby truehd, dts, dts hd ma, pcm, etc.

the dolby digital used for theatrical mixes is usually encoded at a much lower bit-rate than even dolby digital on plain vanilla dvds. yet, you always hear people raving about the audio in movie theatres and hoping that the blu-ray matches the theatrical experience. from a technical standpoint, lossless audio on blu-ray is much "fuller" than theatrical mixes, but few people really have the ears to pick up on the differences.

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What is quite pathetic, is that even the movies/features with Uncompressed PCM, make little to no difference on the whole amount of the disk title amount. I have found from disk to disk varies very little. There is still on average 5 to 6 gigs of "free" space still left over.

Um ok. What you are missing here is that they are not using it to save space so that they can go "hey look my disc has free space left over!". They are doing it so that they can USE that space for something else (another bonus feature, some additional audio tracks, a higher video bit-rate). Therefore most discs will have little space left over because they have packed on as much material as they can fit.

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Honestly, studios are too lazy to spend the R&D time to render the PCM file to the final master. At this point ot boils down to time constraints, cost and impatience that is ruining it for the customer.

This statement makes no sense. DTS HD MA and Dolby TrueHD require additional software and time to perform the compression. Uncompressed audio is much faster, easier and less expensive to add to a release than encoding and then adding DTS HD MA or Dolby TrueHD. And what does R&D (research & development) time have to do with the rest of that statement?

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With Blu-Ray, space is a non-issue.

So not true. Blu-ray does not have infinite capacity. It has greater capacity than DVD, but uses video and audio that requires more space. The same struggles for space exist in authoring Blu-ray that did in authoring DVD.

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the dolby digital used for theatrical mixes is usually encoded at a much lower bit-rate than even dolby digital on plain vanilla dvds. yet, you always hear people raving about the audio in movie theatres

Good point. This is usually due to the much better sound systems theatres employ. High-quality audio codecs do not produce much difference if you have a low end receiver and crappy speakers. So many people these days have those little 'stick' like speakers that come with those low cost surround systems. For them Dolby Digital, DTS, DTS HD MA, Dolby TrueHD, Uncompressed or whatever is going to all sound the same.

For those of us with a good receiver and some decent speakers it does make a difference, especially if you have a keen ear as well. Most listeners don't have to worry about which audio codecs to use because it will not make much of a difference on their sound system, but it's good that the options are there for those who it will make a difference for.

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[Post edited by the_dvd_chef on Apr 17, 2009 - CDT 1:20 AM]

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Um ok. What you are missing here is that they are not using it to save space so that they can go "hey look my disc has free space left over!". They are doing it so that they can USE that space for something else (another bonus feature, some additional audio tracks, a higher video bit-rate). Therefore most discs will have little space left over because they have packed on as much material as they can fit.

Hey look - "When you Consider that 95% of the Blu material I have "looked at" has never exceeded 45 gigs... Advertising and Money making dollars... "

Should have concluded with the sentence "Advertising and Money making dollars already included in that calculated 45 gigs."

Already covered that...

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This statement makes no sense. DTS HD MA and Dolby TrueHD require additional software and time to perform the compression. Uncompressed audio is much faster, easier and less expensive to add to a release than encoding and then adding DTS HD MA or Dolby TrueHD. And what does R&D (research & development) time have to do with the rest of that statement?

Well I guess I should have worded it differently. The Dolby and DTS studio are looking for their cheque and advertising plugs in the movie. It was right before bed... Sorry my bad.

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So not true. Blu-ray does not have infinite capacity. It has greater capacity than DVD, but uses video and audio that requires more space. The same struggles for space exist in authoring Blu-ray that did in authoring DVD.

Really, I didn't know that?

Like I said in some of my previous post(s) in other forum topics, most disks I have looked at usually contain 32 to 45Gigs of used space. So when you take the original 50 storage surface then subtract it from the burned content you get 18 to 5 gigs of "free space". Not being used outside of the feature, special features, trailers, advertising, games, web content interface... Trust me I know. Most feature titles only occupy 20 to 26gigs. The same sizes as the HD DVD's counterparts... Without going into great detail again, the "other" 10 to 25 gigs is being occupied with special features, trailers, games, advertising, and other files.

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[Post edited by ReaggieP on Apr 17, 2009 - CDT 7:22 AM]

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Hey look - "When you Consider that 95% of the Blu material I have "looked at" has never exceeded 45 gigs... Advertising and Money making dollars... "

Should have concluded with the sentence "Advertising and Money making dollars already included in that calculated 45 gigs."

Well I don't know what titles you have surveyed, but being someone who is involved in the authoring process I am used to fighting for space. Yes, some titles end up not having that many bonus features and sometimes you just go ahead and use DTS HD MA because it is normal procedure, but these are certainly not most titles.

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Well I guess I should have worded it differently. The Dolby and DTS studio are looking for their cheque and advertising plugs in the movie..

I don't follow you here. Dolby and DTS do not force studios or authoring houses to use their codecs. In fact we have to pay them to use it. DTS HD MA will run you US$1,500 and Dolby TrueHD US$25,000.

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Like I said in some of my previous post(s) in other forum topics, most disks I have looked at usually contain 32 to 45Gigs of used space.

Well technically a dual layer Blu-ray disc only holds about 46.57GB not 50. It's that same trick they pull with hard-drives and memory sticks and so on. They count it as 50GB because it has 50,000,000,000 bytes, but really there are 1,073,741,824 bytes in a Gig. Anyway it's a stupid technicality but it means you end up with a 46GB Blu-ray disc. So 45GB is pretty much full.

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[Post edited by the_dvd_chef on Apr 17, 2009 - CDT 11:07 AM]

ReaggieP,

Think of it this way: As the DVD Chef says, space on a BD is not infinite. Even if it's already enough for most average-length movies (and very few bonuses), more space would be needed for very long movies ("Gone with the Wind," "Lord of the Rings"), for average-length movies with high-def bonus items, and for very short movies that a studio might want to squeeze onto a BD25 to save money. The more efficient, less space-consuming TrueHD and DTS-MA codecs save them that extra space.

I mean, you don't think the studios are paying that license fee to Dolby or DTS for nothing, do you?

John

Here's is some examples

Twilight 44.7 gigs - The feature itself is 30.3 gigs. Therefore 14.4 gigs is advertisements/special features, and trailers.

Wall-e 36.6 gigs - Disney is a bit messed up on there structure. They create a M2TS file for every chapter. Wall-e was about 30 gigs give or take a few hundred megs for error on my part. Give 6 to 7 gigs for special features and advertisments.

However interesting to note, I don't have the info on hand but I have looked at Several titles such as My Best Friends Girl, Rightous Kill and a few others to see that they were around the 36 gig mark and the features were only 23 gigs.

With the VC-1 coded stuff as much as 7 to 10 gigs smaller than the MPEG 2 and AVC (H.264) stuff. What are you using? At work they have been using a modified version of open source H.264 at work. I don't code, so I really don't know the specifics. Our engineers have compiled new compression algorithms, that we can now stream HD at 4.5 Mbs! It still looks great! Interestingly enough we may see Microsoft try to push VC-1 again to compete. I'm guessing, but it would be intersting.

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The Dolby and DTS studio are looking for their cheques and advertising plugs in the movie..

I said it already. Hence they are making money from the studios. The studios are paying for the licences. LOL I understood it already... You guys both pointed out something that I already stated. No confusion there...
kinda funny though...

One interesting note about the space on the disks chef. The last batch of TDK's with durabis that came in 4 x DL 50 gigs, actually held just under47.4 gigs. Compared to the 2 x DL's I received a few months before proves your 46 gig count. I just got an e-mail last week on a 6 x DL disk drop in price. What are you currently pricing disks at? I curious to know the cost versus the discounted retail price that I pay... Right now I can get them for around $7.30 CDN per disk. That's usually a 10 or 15 pack. What do dealers pay?

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[Post edited by ReaggieP on Apr 17, 2009 - CDT 11:41 AM]