Roogs Benoit

The best DD/DTS comparison I have ever done is taking the original digital audio master and importing it into protools. Then encoding an ac-3 stream and a DTS from that master. Playing back the ac-3 through the Dolby 562 professional decoder and recording back into protools from the digital output of the 562. I then played back the DTS through the CAD-4 professional decoder and recorded back into protools from the digital output of the CAD-4. This way there was no A/D or D/A conversion done at any step. Then I put them all in sync and was able to playback any version at any time even inter cutting the original,DD and DTS tracks. They were all played back through the same D/A converters so there was no difference between Dolby's decoder and DTS's decoder.
What did I find?
I found that it doesn't matter what I found. You will all make up your own minds and my opinion doesn't mean anything.
Have a nice debate.
Roogs

Michael Reuben

That's cold, Roogs.

C'mon, don't leave us hanging like that. (I need a smiley for "pretty please".)

And if it makes any difference, your opinion does matter to at least one person here.

M.

“They’ll just take some stinkeroo movie or some songwriter’s catalog, throw it onstage and call it a show.” -- Zeus, Xanadu (the musical)

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John_Berger

That was cold, but it was brilliant.

DaViD Boulet

Roogs,

I'm with Michael...we just gotta know

If you're not pulling our leg then that certainly would be the best apples-apples comparison possible if one wanted to compare compression-algorithm to compression-algorithm. I state that because it's very possible that *many* of the sound-quality issues listeners consistently hear between various "formats" like DTS or DD may have many factors that come into play in practice other than compression-algorithm.

Some questions do remain given what you describe: Were identical bit-rates used during compression? What was the resolution of the source PCM digital multitrack signal? Was that resolution preserved (I understand that DD can encode up to 20-bit words) or downconverted to the 16-bit level for either or both codecs? Were any additional processing steps employed or avoided? DD has a host of manipulation tools like dialog normalization and EQ etc. that often get used inadvertantly by mastering houses without much expertise.

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Michael Reuben

Good God, Roogs, don't go the private message route! Otherwise Boulet will be citing you as one of his unnamed audiophiles for years to come.

M.

“They’ll just take some stinkeroo movie or some songwriter’s catalog, throw it onstage and call it a show.” -- Zeus, Xanadu (the musical)

"What kind of movies would there be if everyone in them had to do what we thought they should do?" -- Roger Ebert

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DaViD Boulet

Then again he might tell me that he heard no difference!

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Lew Crippen

Interesting that Roogs made his post while I was writing that objective tests had not been performed.

¡Time is not my master!

John_Berger

Absolutely. This world would be a very boring place if everyone agreed with everyone else. But the suggestion and subsequent approval of the complete removal of an audio format that is not "up to par" with DTS (although not by much) is not "disagreement".

It's not that I disagree with anything that was said regarding the technology. I'm quite certain that if Roogs tells us what he found (which I hope he will) that DTS will come out ahead. But the concept that DTS is so far ahead of high bit rate DD as DD is to monaural is what always irks me and is exactly what happens every time these DD/DTS threads get started.

So, I guess that it's not that any one big thing that was said in this thread set me off out of nowhere but rather the culmination of small things over time that were ignited by the suggestion that DD should be removed entirely to make room for DTS.

I'm not sure about that. There have been been threads in this forum about how Queen is ignoring DD on their DVD releases to the point that whoever started the one thread got an explanation from Brian May that they were avoiding DD 5.1 because of the loss to its compression but would consider it for future releases.

Very close. You missed the apostrophe. (It's "anyone else's" as it represents ownership of the noun "opinion".)

And again, I don't doubt that. There is very little doubt in my mind that DTS is technologically and audibly superior to DD. It's the DEGREE of superiority that I find very, very difficult to believe, particularly when put on a scale of diminishing returns with monaural, stereo, and ProLogic on the same scale.

The real issue with me is the air of "elitism" exuded in just about every DTS thread as though I don't really own a true DVD or a true home theater system unless I have DTS, and DVDs are just so-o-o sub-par if they don't have a DTS track, and it's unconscionable that I don't see it that way because DTS is just so-o-o superior, and DD even at its highest bit rate is just so-o-o inferior, and this tonal quality is so-o-o much clearer only with DTS, and that tonal quality is so-o-o much clearer only with DTS, so we should put every effort into DTS because those who don't listen to it will never understand, so to hell with 'em, let them suffer with Dolby ProLogic so we can reap the benefits of our so-o-o superior DTS system, blah, blah, blah, yackety smackety. It gets old quickly.

You know what? Legolas' arrow whizzing by in the distinct right-rear channel and the Horn of Gondor blaring in the distinct left-rear channel sound pretty damned impressive to me as do numerous other instances in numerous other movies that effectively use DD 5.1, and it's infinitely better in my opinion than two-channel stereo.

John_Berger

Ah, but if he doesn't bother to tell us the results, did the test really take place?

Sean*O

ROOGS! You Rascal!!!

Adam Barratt

All DTS recordings (I see no qualifications here)? Including the numerous recordings that used 16-bit masters? If a 16-bit PCM (master) recording has these "harsh" highs, then how can DTS encoding of this recording transform them into something "silky smooth"? This seems to suggest that DTS isn't in fact accurately reproducing the source, but actually improving it. That's an argument I've never heard before (at least not one seriously mooted)!

I'm not touching the use of analogue "smoothness" vs. digital "harshness" in a DTS vs. Dolby Digital discussion with a ten foot pole. I don't have a set of bass-enhancing crystals or audiophile-grade masonry bricks, so I'm not qualified to comment.


Try Labyrinth (original release), but this sort of comparison wouldn't reveal much I suspect.


And some also heard DTS with no pre-conceived expectations (this was at a time when virtually no-one had even heard of it) and thought to themselves "That's it?". This was also at a time when genuine comparisons were difficult, and when they did occur notions such as mastering differences, re-equalisation or dialog normalization weren't even a consideration.


This is certainly true, but it has no bearing on a DTS discussion. The comparative scale in the DTS debate is much smaller.

I can respect your opinion and preference for DTS, and it's clear these opinions are strongly held. However the basis of this opinion, other than your own ears, seems to be pure (and often uninformed) speculation and invalid/inappropriate comparisons on your part.

As for the original question, given the current mastering norms and assuming a properly prepared Dolby Digital soundtrack is provided, I would be perfectly willing to lose a DTS soundtrack. Not so I don't have to change a disc (a few seconds to change a dics is nothing really), but to ensure picture quality wasn't unnecessarily compromised by redundant data consumption.

Adam

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Roogs Benoit

OK, to answer David's last question on how the test I did was done, I used a 24 bit master. There were no additional processes introduced in the chain when the transfers were made. The Dolby 562 was in a mode that bypasses all dial norm, compression and downmixing parameters (this mode is representative of the original master used). A data rate of 448 was used for the ac-3. The DTS was encoded through the CAE-4 hardware encoder at a rate of 754 and decoded as I stated previously.
The results were very interesting. I depended on who was listening, what program material was used (both music and film soundtracks were used), at what amplitude etc. Let me say first that both codecs work very well and each company should be proud of their process. In short the differences between DD and DTS were minimal. Both sounded great but each had slightly different anomallies in playback. Some people heard a slight difference others heard no difference at all. They both gave a very good representation of the master.
My conclusion was that the codecs being this close shows me that if you are hearing a vast difference between DD and DTS on your systems at home that there is some processing going on that you are un aware of. It may be user adjustable or something that the manufacturer has introduced without your knowledge. But the actual codecs are close enough that you must have exceptional hearing with a system that is better than that in most studios to hear any noticeable difference. This was an A/B(C) test. 'C' being the original master and we still had difficulty telling a difference between tham. Those of us who heard the difference (almost all of us) had difficulty describing what that difference was.
On another note: it was interesting seeing the reaction of some of the audio professionals when the women who work in the office could tell the difference as well as they could. I say this because women have better hearing than men on average and the differences were very slight. They would even describe the difference in a similar manner.
So if you hear a significant difference on a disc that used the same master, your system itself could be the difference.
That is just my findings and opinion. Your milage may vary.
Have a nice day,
Roogs