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Discussion Starter #1
Lets hope that in the future at some point, we can have real higher quality sonics from the new DD and DTS formats with HD DVD and Blue Ray. Is my understanding correct that the HD DVD and Blue Ray players coming out this year will not support the new formats, but will only support existing DD and DTS? And that we need to wait for a later generation of players for the new sonic formats?


Even assuming that these players play the new formats, what are the problems from a sonic perspective such that the new formats may well not sound any better in many if not most systems?


1. HDMI is still under development for digital audio transmission and the potential sound quality remains to be seen, at least via HDMI transmission.

Maybe it will take years to develop that sound quality, just like it did redbook CD!!!


2. So you say, what about having the HD DVD or Blue Ray player do the decoding? I agree, this is potentially a viable option meanwhile. But as a practicality, we audiophiles will find that not all players sound the same in this regard, and a company like Theta or Meridian later on (if the formats survive) developing the player with better DACs will sound better.


3. The next limitation is the multi-channel input of the surround processor.

Some surround processors digitize the analog multi-channel input. All surround processors have the multi-channel input in the same piece of surround processor equipment as all the digital and analog stuff, thereby degrading the sound - except guess which surround processor? (That's right, if you get the Theta CB3's Six Shooter).


My prediction is that of all the high end surround processors out there, the Theta CB3 is the most future proof thanks to the Six Shooter. But will anyone else like Meridian follow Theta's lead - my bet is for the next few years, no, that other companies like Lexicon and Meridian will continue their on board analog multi-channel inputs and wait to see how successful are the new formats. Theta already developed the Six Shooter basically for multi-channel SACD and DVD-Audio and now those of us owning the Six Shooter will get its benefit for

the new formats when they start using the new sonic formats.
 

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I disagree on adoption of internal decoding by surround processors. The hold-up has been getting a digital transmission standard finalized. The studios want HDCP for native hi-rez audio transmission of the next gen formats. They're getting that in the HDMI 1.3 standard that hopefully will drop by mid-year. At that point, it makes a lot more sense for Lexicon, who has not included HDMI switching yet into their processors, to get on board with both HDMI switching for video and internal decoding of the new formats. From my conversations with Lex reps, they seemed reluctant to add HDMI with too much unknown about whether another hardware upgrade would be needed later to conform to 1.3 after it was finalized. I'm not talking about the next gen DD and DTS format decoding hardware but rather just the HDMI associated transmission hardware. My personal belief is that the upgrade will come in the form of a new flagship processor to replace the MC-12 late this year or early next year.


Jeff
 

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I think the real message here is that at least for the time being, the importance of these surround formats rests in the new DVD players, not the processor. The processor will simply be a gain control for a while. While my Lexicon can act as a true 5.1 pass through, it can also 'digitize' things for bass management, time alignment, crossovers, speaker distances and other post processing goodies. The processor will assume second class status for a while. More sophisticated HD players (with good bass management, flexible crossovers, time alignment, etc) with analog outs will be what we are after until full digital ins and outs on the new generation processors arrive!
 

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Discussion Starter #5
Quote:
Originally Posted by thebland
I think the real message here is that at least for the time being, the importance of these surround formats rests in the new DVD players, not the processor. The processor will simply be a gain control for a while. While my Lexicon can act as a true 5.1 pass through, it can also 'digitize' things for bass management, time alignment, crossovers, speaker distances and other post processing goodies. The processor will assume second class status for a while. More sophisticated HD players (with good bass management, flexible crossovers, time alignment, etc) with analog outs will be what we are after until full digital ins and outs on the new generation processors arrive!


I am well setup with my CB3 and Six Shooter. As my speakers are equidistant from my front center sweet spot, I am already time aligned without needing to use any digital time alignment in the surround processor. And for the .1 channel,

I have a pass through from the front left Aerial sub to the front right Aerial sub, and I can do the same with the surround sub if I want, too. So I won't be sweating until manufacturers properly develop sonic quality from tne new audio formats (if ever).


Most folks may not care if their surround processor's multi-channel inputs digitize the incoming analog audio of the new sonic formats - I do. In my system, it is clearly detectable, just as is the different in routing say two channel SACD from my Theta Compli to the Six Shooter as opposed to the CB3's internal analog direct or analog bypass.
 

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I'm not sure I agree with Jeff here; I envision a different separation of responsibilities.


I personally think that the task of decoding DD+/DTS-HD and other compressed formats ought to lie with the player itself. Before, this wasn't optimal because there wasn't a way to deliver the uncompressed audio digitally. But with HDMI, you can. So the decoding of these formats can safely be done by the source device without forcing an extra D/A-A/D conversion.


Uncompressed, multichannel PCM can be sent to the processor over HDMI, which would handle things like room correction, bass management/crossovers, matrixing (say, 5.1 channel sources to 7.1 or vice versa), and so forth. In particular I do not think that bass management, crossovers, etc. ought to ever be in the source device itself. After all, if you have 10 source devices, why should you have 10 different bass management settings?


What's nice about this separation is that it prevents people from having to upgrade their room and speaker-related processing every time a new audio coding scheme comes out. I mean, let's face it, many people spend considerable time dialing in their processor/amp/speakers for the perfect result. It is a shame to have to scrap even a part of that work and start over just because of some new audio format. If every new source device supports high-res PCM over HDMI, then the processor can be format agnostic.


Yeah, I know many of us are going to have to upgrade now because HDMI processors aren't commonplace yet; but that should be a one-time investment.
 

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Michael,


Not to mention that you don't have to add DSP horsepower to decode and process the new formats :)


Cheers,
 

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Mike, I agree with you. Perhaps I should've said the processor and DVD player will be of equal importance.... I'd like to see what you are thinking of..Yes, it would be simpler and cure headaches. I would prefer to see post processing done in the processor. Decoding in the DVD player would be fine with me. That said, I'd need at least 6 HDMI inputs in my next processor (preferably 8).


We''ll see....
 

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First off, you have the formats incorrect...


As a DTS fanboy ;) you should know it's DTS-HD :D



Quote:
Originally Posted by Steve Bruzonsky
Lets hope that in the future at some point, we can have real higher quality sonics from the new DD and DTS formats with HD DVD and Blue Ray. Is my understanding correct that the HD DVD and Blue Ray players coming out this year will not support the new formats, but will only support existing DD and DTS?
No, it's not correct.


The Toshiba players will handle Dolby Digital, Dolby Digital+*, DTS and DTS-HD* in surround and Dolby TrueHD* in stereo.


* = New formats


The Blu-ray players will handle all formats in surround.


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And that we need to wait for a later generation of players for the new sonic formats?
Nope, see above.


Quote:
Even assuming that these players play the new formats, what are the problems from a sonic perspective such that the new formats may well not sound any better in many if not most systems?
Lossless audio will sound better than lossy audio. I don't know where you're drawing this idea from.

Quote:
1. HDMI is still under development for digital audio transmission and the potential sound quality remains to be seen, at least via HDMI transmission. Maybe it will take years to develop that sound quality, just like it did redbook CD!!!
That's not completely correct. PCM streams have been supported for a while with HDMI 1.1. HDMI 1.2 added support for DSD streams.


All HDMI 1.3 does is add native transfer of Dolby Digital+ and TrueHD and DTS-HD. This will increase DSP requirements by 100-150 MIPS, possibly more if we start having to deal with 192K PCM streams and DSD streams.

Quote:
2. So you say, what about having the HD DVD or Blue Ray player do the decoding? I agree, this is potentially a viable option meanwhile. But as a practicality, we audiophiles will find that not all players sound the same in this regard, and a company like Theta or Meridian later on (if the formats survive) developing the player with better DACs will sound better.
Well this is not really a choice as all the high-end companies are taking a wait and see approach until the dust settles from the technological showdown.


Quote:
3. The next limitation is the multi-channel input of the surround processor. Some surround processors digitize the analog multi-channel input. All surround processors have the multi-channel input in the same piece of surround processor equipment as all the digital and analog stuff, thereby degrading the sound - except guess which surround processor? (That's right, if you get the Theta CB3's Six Shooter).
Digital devices deserve digital pathways. This will become increasingly important as more loudspeaker companies go down the digital pathway. I look forward to the day that products like NHTs xD system, and Phase Tech's d'ARTS system can take a digital input directly. The folks in the UK (Meridian and Tannoy (Eyris iDP)) need some digital input competition. It'll improve the state of the art for everyone :)


Using an analog input is a compromise as you give up all of the functionality of your SSP, such as Time Alignment, Bass Management and Room Correction tools. All of these functions are more advanced in an SSP than a source and room correction doesn't exist at all.

Quote:
My prediction is that of all the high end surround processors out there, the Theta CB3 is the most future proof thanks to the Six Shooter. But will anyone else like Meridian follow Theta's lead - my bet is for the next few years, no, that other companies like Lexicon and Meridian will continue their on board analog multi-channel inputs and wait to see how successful are the new formats. Theta already developed the Six Shooter basically for multi-channel SACD and DVD-Audio and now those of us owning the Six Shooter will get its benefit for the new formats when they start using the new sonic formats.
I'll sit back and listen on my non-Bruzonsky approved Meridian gear, using stock power cords and cheap ICs just to add insult to injury :D


Cheers,
 

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Discussion Starter #10
Quote:
Originally Posted by John Kotches
I'll sit back and listen on my non-Bruzonsky approved Meridian gear, using stock power cords and cheap ICs just to add insult to injury :D Cheers,
FUNNY!


As always, I defer to John Kotches when it comes to the latest info re surround sound, equipment, etc. One of the reasons I started this thread was to get more accurate info without having to wade through other long threads, knowing that John was bound to come here and get his feet wet.


Nothing wrong with your Meridian setup, John. Wish I was in the area to demo.
 

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From what I have gathered, it will take up to 15Mbit of data rate for lossless audio in surround sound. I am not sure I would want to have that much of my bitrate tied up with audio if it is going to come at the expense of the video. These new formats will peg out at 36 mbit, IIRC, so that would leave us with less bitrate for video than D-Theater. While newer video codecs will help the bitrate issues on the video side it is certainly an odd tradeoff to have lossless audio and more compression in video to make it happen. I can see it for concert videos and high resolution audio playback but I don't really see it as the best solution for many titles.


Don't get me wrong, I think lossless audio is great. I just think it is going to eat up way too much of the bitrate for my tastes. I hope I am wrong about this...
 

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Quote:
These new formats will peg out at 36 mbit, IIRC, so that would leave us with less bitrate for video than D-Theater.
First of all: HD-DVD is 36Mbps max, but Blu-Ray is 48Mbps. Blu-Ray has a bit of an advantage there. Secondly, even if we grant your 15Mbps number, that leaves 21/33Mbps for video. For next-gen video codes (VC-9,H.264), that's more than enough; MPEG-2 might be a bit dicey at 21Mbps, but that's where Blu-Ray's higher bandwidth may come in handy.


Now, let's look at that 15Mbps audio number. 8 channels of 24/96 PCM is 18.432Mbps uncompressed. But in fact, few movies are mastered at that rate, right? John K. probably knows better than I, but I think the common format is 20/48, which even with 8 channels gives you only 7.68Mbps. Tack onto that some lossless compression, and it seems to me that a lossless standard track could fit under 5Mbps, and a 24/96 track at under, say, 12Mbps.


On the other hand, I believe the 36/48Mbps total includes all parallel tracks: multiple languages, DD back compatability, etc. If that's right, then don't forget to subtract a fraction of a Mbps for each of these alternate tracks.


Overall, I'd have to say I'm not too worried about high-quality audio eating into video quality---particularly if a next-gen video codec is used.
 

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Quote:
Originally Posted by Mr.Poindexter
From what I have gathered, it will take up to 15Mbit of data rate for lossless audio in surround sound. I am not sure I would want to have that much of my bitrate tied up with audio if it is going to come at the expense of the video. These new formats will peg out at 36 mbit, IIRC, so that would leave us with less bitrate for video than D-Theater. While newer video codecs will help the bitrate issues on the video side it is certainly an odd tradeoff to have lossless audio and more compression in video to make it happen. I can see it for concert videos and high resolution audio playback but I don't really see it as the best solution for many titles.
The assumption here is that (for example) 22 Mbits/second MPEG-2 is better than 14-15 Mbits/second of MPEG-4 or VC-1. Everything I've read and seen seems to indicate that this is not the case.

Quote:
Don't get me wrong, I think lossless audio is great. I just think it is going to eat up way too much of the bitrate for my tastes. I hope I am wrong about this...
Here's some numbers to consider:


In typical movie soundtracks at 48K and we're talking about 3:1 data reduction (or higher) for typical movies.


7.1 @ 48K requires only 9.2 Mbits/second @ 3:1 we're talking about ~3 Mbits/second. If it's a dialog heavy movie with minimal effects, it is conceivable that the reduction is even greater.


7.1 @ 96K requires 18.4 Mbits/second @ 3:1 we're talking about 6.1 Mbits/second. It's going to be a while before H'wood is actually producing movies @ 96K.


Your assumption here is that everyone will use MPEG-2 encoding. With MPEG-4 or VC-1 encoding at an average bit rate (ABR) of 15 Mbits/second you will be just fine on PQ and still have plenty of room for lossless audio for the primary language soundtrack + additional soundtracks in DD/DTS while living within your bandwidth and space storage constraints.


Regards,
 

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As an FYI, movies compress better than music. There's a lot of empty space in movie soundtracks that compresses down very well :)


Cheers,
 

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Some clarifications...


Neither the Sony nor the Pioneer BD deck has onboard decoding for anything beyond DD/DTS. Unofficially, they can pass DD+ and lossy DTS-HD MA over HDMI (both are HDMI 1.2a compliant); it's HDMI 1.3 that's necessary for passing DTHD (AKA Lossless Dolby) and lossless DTS-HD MA streams. Pioneer seems more adventurous in doing whatever is necessary to support the unofficial passing of DD+ and lossy DTS-HD MA...Sony is playing it safe. That said, the Sony is capable of extracting the legacy streams (using simple profile decoders) of the new codecs, as available (e.g., although it can't decode DD+, it can ferret out the IS0 core DD 5.1 stream if DD+ encoding was used).


The specs on the Toshiba decks were apparently altered at the last minute to note that DTS-HD decoding is *only* for the core DTS 5.1 stream. I would argue this violates the HD DVD spec, but apparently it doesn't. This "issue" is still kind of up in the air...how the A1/XA1 actually "decode" DTS-HD is still the subject of much debate (e.g., is it an actual full decode, or just a partial decode of the core a la DD+ simple decoding of the core?).


Lossless DTS-HD MA maxes out at a whopping 24.5Mbps VBR as spec'd for Blu-ray.


Blu-ray supports (optional in the player) 27.648Mbps CBR LPCM.


In-player decoding is the only way to take advantage of the new audio codec mixing features as well as the new format interactive features (e.g., menu button sounds, etc.). DD+, for example, supports up to 8 independent substreams...and they can be mixed willy nilly if so authored (e.g., director's commentary in substream IS1 is mixed into the main IS0 track). The days of passing raw unencoded streams to pre/pros or AVRs--assuming disc authors take advantage of the new capabilities--might be coming to a close...as Michael noted, LPCM via HDMI is the "right" way to handle audio for both formats. Whether audiophiles adapt to the new world order, though, remains to be seen. :)
 

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The other very important thing to point out with the newer audio compression that gives numerous advantages is that it is not fixed-bitrate like current DD and DTS are.

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As an FYI, movies compress better than music. There's a lot of empty space in movie soundtracks that compresses down very well
I think the non-fixed bitrate is what you're getting at here, which is definitely a huge advantage.

Quote:
Overall, I'd have to say I'm not too worried about high-quality audio eating into video quality---particularly if a next-gen video codec is used.
I would have to agree with michael. In fact, I expect many discs to have fairly similar bitrates as current DVDs, which will be pretty miniscule. I think it may be a while before we start to see high-res soundtracks on these formats that run at these higher bitrates, but that is just my hunch on the matter.
 

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Quote:
Originally Posted by ChrisWiggles
I think the non-fixed bitrate is what you're getting at here, which is definitely a huge advantage.
No Chris, that isn't what I was getting at.


If one were to take a movie soundtrack and one were to take music and compress them both with Dolby TrueHD, the movie soundtrack would end up with greater compression because there's a lot of times when there is minimal activity other than the center channel.


The same would hold true for DTS-HD.


Cheers,
 

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Quote:
Originally Posted by John Kotches
No Chris, that isn't what I was getting at.


If one were to take a movie soundtrack and one were to take music and compress them both with Dolby TrueHD, the movie soundtrack would end up with greater compression because there's a lot of times when there is minimal activity other than the center channel.


The same would hold true for DTS-HD.


Cheers,
Yes, that's my point, but that hinges on a non-fixed bitrate. You can't take advantage of that in a plain DD/DTS environment because they have fixed bitrates, so when there's not much going on you're wasting data. I don't see how this can be taken advantage of in a fixed-bitrate encode at all.
 

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what are the video codecs for HD DVD and Bluray?
 

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John, I was unaware that BluRay was 48 Mbit. While I am not assuming that 22MBit MPEG2 is better than 14 Mbit VC-1 or MPEG4, I am just thinking in terms that I am familiar with. I haven't worked with MPEG4 enough to know what rates I would need to be satisfied with the results. I do know that I never complain about having too high a bit rate when it comes to final image quality.


I do know of some production that is planned to be mastered in 24/96 for a special anamorphic HD project but I agree that Hollywood isn't about to send us the best quality yet.
 
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