Dolby Digital vs. DTS (1 Viewer)

[SeanA]

I have never bothered changing the default surround audio setting in the menu of a DVD, but I am now wondering if there are any advantages of one format over another ? It seems most DVDs use Dolby Digital sound processing as a default, but the "Chicago" DVD, for instance, allows one to choose the default Dolby Digital 5.1 or DTS 5.1. If Dolby Digital is the default, does this mean the original sound track was recorded in that format ? If so, why would one make any other choice than the default ?

 

[Lev-S]

dts averages at 754 bitrate vs Dolby Digital at either 384 or 448. It's just like how a 192 kpbs mp3 sounds better than a 128 kbps mp3. Is it noticable? To some no, to others (like me) yes. BTW, they also mix soundtracks for theater surround SDDS (Sony Dynamic Digital Sound - I think...) which is like 8.2 or something like that. Would you pick DD over that because it's default?

 

[ChrisWiggles]

This has been debated to no avail. I listen to DTS when available usually. Maybe because their logo is cooler. They both sound great to me

 

[Michael Reuben]

If so, why would one make any other choice than the default ?

Some people think DTS sounds better. This supposed superiority has been endlessly debated but never conclusively established.

M.

 

[SeanA]

It's just like how a 192 kpbs mp3 sounds better than a 128 kbps mp3

I didn't know that. But I guess there is probably a point of diminishing return where more bit-rate just doesn't make a difference to the sensitivity or our ears. ** I agree that 192 sounds better than 128 kbps, but for DD vs. DTS, we are talking 400 vs. 750 kbps. That's quite a jump up. I suppose I will choose DTS in the future, if given the option, just to be sure I am getting the best sound output. But it puzzles me why DD would be the default so often if DTS is inherently better ?

** This is somewhat related to my statement of "point of diminishing return". Did you know that cats have such quick visual acuity that they can pick up the formation of the individual horizontal lines on a TV screen ? This is why for most cats, TV is not interesting. But there are some cats with slower vision that can actually make out the images that we do. So if your cat watches TV, it is actually has "slow" processing upstairs and is not really a smart cat as you might have thought.

 

[Michael Reuben]

if DTS is inherently better

Well, if you want one person's opinion (and I've been listening to DTS tracks since the laserdisc days), it isn't.

M.

 

[Wayde_R]

On a couple of DVDs I did side by side comparisons of DTS vs DD. Both, at least in my system sounded better in DTS.

Gladiator. The execution scene near the begining. "Sometimes the blade sticks." Watch that whole scene in both. I think the details in the wind going from front to back and how it changes direction with the perspective of camera's pov is amazing. I don't notice it in DD.

Mulon Rouge. The "we could be heros" duet between Kidman and McGregor on the rooftops (near the begining of the movie)that ends in the lines from the Elton John song...'how wonderful life is now you're in the world.' There is simply no comparison between the DD and DTS version. DTS is so much clearer in the softer details, at the very end of that scene a guy in a window echos (whispers) that last Elton John line and in DD (at a medium volume) it's very low, in fact almost muffled. In DTS it's quite clear, each word is clearly enunciated.

I use DTS where available. Those are just my head to head comparison examples. If you have those dvds let me know if you find the same results.

 

[Jeff Gatie]

Just to echo what Michael Rueben said, comparing DD to DTS is not like comparing two different compression levels of the MP3 codec. With MP3 you are comparing 2 compression levels within the same compression algorithm - of course they will sound different. However, DD vs. DTS is comparing two different codecs, big difference. If DD's algorithm is more efficient than DTS (I'M NOT SAYING IT IS!!!), then it is entirely possible for DD to sound better with a higher compression rate than DTS does with a lower compression rate. The idea that "DTS uses a higher bitrate, it must be better" is one of the biggest fallacies in the DTS vs. DD debate and is easily proven to be a falsehood if you know anything about compression techniques.

 

[JamesHl]

I'll say what I always say in these threads.

The difference is in the mix, not the format.

 

[Paul.Little]

The reason DVDs default to the Dolby Digital soundtrack rather that the DTS soundtrack is equipment driven. If you own a receiver with a digital input for a DVD player, it definitely has a Dolby Digital decoder built into it. It may not have a DTS decoder built into it. There are a significant number of Digital Surround Sound receivers in peoples' homes that do not have DTS capability. The DTS soundtrack can do some damage to speaker systems if you attempt to play it back through one of these systems at normal home theater volume levels. That's why, on many DVDs with a DTS soundtrack you get an "are you sure" type message after you select the DTS soundtrack.

As for sound quality, I have done a little bit of listening. While I have heard DD soundtracks that sounded better that the DTS counterpart, most of the time I prefer the DTS soundtrack.

 

[Michael Reuben]

most of the time I prefer the DTS soundtrack

Most of the time, the DTS track is louder. This is due to technical mastering differences that most users are unaware of and don't adjust for. I can't prove it, but I remain convinced that this difference in volume accounts for the vast majority of expressed preferences.

M.

 

[FeisalK]

... can't prove it, but I remain convinced that this difference in volume accounts for the vast majority of expressed preferences.

I've heard it quoted many times that louder is often perceived as 'better' - and first impressions often stick, too.

 

[Elbert Lee]

I prefer DTS over DD, but that's just me. Doesn't turn a lousy film into a good film. However, you'll hear more professional and non-professional bias toward DTS over DD.
The reason why DVD discs set the player's audio default on DD over DTS is because DTS outputs a loud "pink" sounding noise if the digital connection from the player goes into a preamp without a DTS decoder. The noise can possibly be loud enough to cause distortion and damage your speakers.
Therefore, it's "safer" for DVDs to automatically select the DD soundtrack over DTS.

 

[Paul.Little]

Most of the time, the DTS track is louder. This is due to technical mastering differences that most users are unaware of and don't adjust for. I can't prove it, but I remain convinced that this difference in volume accounts for the vast majority of expressed preferences.

I am aware of the level differences and have tried to compensate for them when comparing soundtracks. Not every time, but usually, the DTS soundtrack simply sounds more encompassing, with better detail coming from the surround speakers. Just my opinion.

 

[LanceJ]

DTS sounds better to me also--cleaner with better high frequency detail (movies and dvd-audios). And I understand the volume level thing, but for me this isn't a factor in my preference.

LJ

 

[David Judah]

While there are differences due to different mixes from different masters, I suggest another possibility that might come into play more often that has not been discussed to my knowledge(if you read Roog's comments in the thread Michael mentioned, he said it is not common to start from different masters in his experience).

Back when DTS & Dolby were releasing their position papers on each other's codec, DTS mentioned that Dolby's encode/decode combo exhibited phase anomolies with the LFE and Main channels to the point of them being up to 225 degrees out of phase. Of course, anytime a company makes claims about a competitor, I take it with a large dose of skepticism.

After digging for some information to corroborate those claims, I found at some Pro Forums that it was a known issue. Some of the engineers mentioned that it was of the utmost importance when working with Dolby Digital to carfully monitor the mix with bass management, because it could sound perfectly fine in the studio but acoustical and electrical cancellations could wreak havoc on the quality of the soundtrack when played back through consumer equipment in people's homes.

If it slipped through and made itself on to DVD, the DTS soundtrack could sound fuller with more body or weight in comparison(even higher up in the frequency harmonics). Interestingly, those kind of characteristics are often mentioned when some are describing why they prefer a particular DTS soundtrack over its DD counterpart.

In addition, it's not going to manifest itself on every disc because of the experience of the enginners and the differing equipment used in the various mixing studios.

I thought it was very interesting. There is alot that goes on behind the scenes that we are unaware of. Reading and discussing some of the issues engineers are faced with was very eye opening and informative.

DJ

 

[Michael Reuben]

Fascinating stuff, David. It could explain a great deal. Do you have any links to the discussions in question?

it's not going to manifest itself on every disc because of the experience of the enginners and the differing equipment used in the various mixing studios

And it probably wouldn't have shown up in Roogs Benoit's tests, where I'm sure there were NO mistakes in the DD encoding.

M.

 

[SeanA]

Wow... I was away for a couple of days, but it is amazing how much good information and debate comes from this forum with the right questions. Thanks guys !!!

 

[Lewis Besze]

After digging for some information to corroborate those claims, I found at some Pro Forums that it was a known issue. Some of the engineers mentioned that it was of the utmost importance when working with Dolby Digital to carfully monitor the mix with bass management, because it could sound perfectly fine in the studio but acoustical and electrical cancellations could wreak havoc on the quality of the soundtrack when played back through consumer equipment in people's homes.

Yes Dolby mention this on their site,I believe on their "white paper"of MCMM under bass managment.
Dolby specificaly recommends to engage proper bass managment,after encoding so the engineer can check for phase anomolies. Dolby doesn't hide this. Here is a link:http://www.dolby.com/tech/Multichannel_Music_Mixing.pdf
The interesting part is that while in all pre/pro/receiver the BM apllies to DTS as well,DTS does recommend for full range all around+sub and no electronic distance compensation.
I wonder why?

 

[David Judah]

Michael,

http://www.musicplayer.com/cgi-bin/ultimatebb.cgi
I especially like the Surround Professional Forum, but there is alot of good info. in some of the other ones, as well. The magazine, started by Tomlinson Holman is also an excellent resource.
http://recpit.prosoundweb.com/
http://www.3daudioinc.com/cgi-bin/ultimatebb.cgi

There are many more links available from those sites too.

Lewis,

That paper was written just a few months ago. It certainly is in Dolby's interest to make the professionals aware of the issue so quality isn't compromised.

DJ