The Battlefield: Dolby Digital vs dts (Official thread)

[tomdkat]

Ok, with ALL of the GREAT Dolby Digital vs dts discussion that HAS gone on in the past and will CONTINUE to go on, I've decided to start an "official" (oh no, not another one of those) thread so the discussion won't get lost as the message board fields new messages, etc.

So, I ask that you keep your Dolby Digital vs dts discussion to THIS thread so we can have ALL of this great info in ONE place.

Since there is discussion scattered about, I will post links to current threads HERE and ask the discussion be resumed here..

Thanks....

"Let's get ready to rumble!!!!!!!"

You can find technical info on Dolby Digital (AC-3) here:
http://www.dolby.com/tech/

You can find technical info on dts here:
http://www.dtsonline.com/home/info.shtml

Here are some current threads of discussion:

DTS being lowered in volume at cinemas?...thank God.
Have we been brainwashed to like DTS?
What is DTS?
(From AVS Forum) http://www.avsforum.com/avs-vb/showt...hreadid=159966

I will update this thread as I find more...

Peace.....

[Oscar Antonio M]

Thanks Tomdkat!.

Ok i want to remark all the differences i have heard in DTS tracks vs. DD in my DTS DVD´s.

Titan A.E: 3dB difference. Stronger and more controlled bass, better clarity and more detail and better separation
Chicken Run: 3dB difference, better surrounds, better clarity, better bass and more detail and better separation
Apollo 13: N/A
The Lost World:Jurassic Park:N/A
Twister:No difference
Gladiator: 6 db difference much better clarity, much better and more controlled bass, much more detail and much better separation
Lady and the Tramp 2: 0db difference, better detail and bass and better separatio
Cast Away: 3 db difference, better clarity, bass and more detail, and better separation
Remember the Titans: 3 db difference, better clarity, bass and more detail and better separation.
U-571: 3 db difference, much better bass, much better clarity and detail and much better separation.
Shrek: 3-4 db difference, clearer dialouge, better clairty, much better bass and much better separation.
Jurassic Park III: 3 db difference, better clarity, bass,detail and separation
Pearl Harbor: 0 db difference, better bass and detail and separation.
Moulin Rouge: 3 db difference, much better separation, more clarity, detail and bass.
The Mummy: 3 db difference, better clarity, bass, separation and more detail.
The Fifth Element: 0 db difference, better detail and bass and separation a bit better.
Cinderella II: 4 dB difference, better bass, clarity and separation and more detail
The Fast and the Furious: 4 db difference, much better separation, clarity and bass and more detail.
The Grinch: 4 db difference, better clarity, detail, separation and bass.
K-PAX: Much bettter separation, better clarity, detail and bass.
Metropolis: 9 db difference , much better clarity, bass and detail and separation.
A.I. 3 db difference, better clarity, bass, detail and separation
The Royal Tenenbaums; 3 db difference, much better detail and separation, clarity and bass

All right, thats it.

[tomdkat]

After quickly perusing the various posts in the above listed threads, I thought of some comments of my own.....

Regardless of which audio track *can* be proven to be the "best", how will the consumer know that? Won't they have to use THEIR ears to judge which they like the best?

When my brother was visiting me from Florida, I did some DD vs dts and THX DD vs THX dts audio comparisons for him using U-571 as the test material. I would think MOT of you would agree that U-571 has great audio, both DD and dts.

I played the SAME scene (opening depth charge scene) for the same duration, first with the DD audio then the dts audio, BOTH with THX processing OFF... then a second round with THX processing ON.

Yes, my brother could HEAR the difference between the DD and dts audio and REGARDLESS of the THX processing, he opted for the DD audito each time. He just preferred the "sound stage" presented by the DD audio. The sound that came from the front speakers didn't sound like it was coming from any particular speaker, but from the front and he liked that. With the dts audio, the dialogue (basically reporting how busted the sub was) came distinctly from the center speaker. With the DD audio, this sound seemed to come from the front, but didn't sound as distinctly from the center channel.

Does this mean HE thinks DD is "better" than dts? Probably... does this mean DD *is* "better" than dts? Probably not. Just because I like dts audio over DD, why must everyone around me also have the same preference?

Like IndyPhantom indicated, dts can sometime be "overbearing" in the home environment, something the THX processing specifically tries to address.

I had some friends over once and gave them a dts demo using Gladiator and they LOVED it! They thought dts ROCKED! Then I played the opening battle scene again, which is what I played the first time around, but with THX processing enabled and they were less enamored with the audio and preferred the THX-less version. Why? Because it sounded more "dynamic" to them. How did it sound more "dynamic"? Well, for one the highs (like when the archers where shooting the bows) were much higher, and sharper WITHOUT THX processing than WITH THX processing.

I don't think this, alone, defines how the dynamics of the audio changed w/ THX processing but it gave THEM the perception of different dynamics.

As for TPM DD EX audio, the BEST comparison should be between the TPM LD and any dts DVD. Even though the TPM LD and DVD use basically the same mix, the 10db difference in volume between the LD and DVD (not to mention the xdb difference in volume between the TPM DVD and other DVDs) can make the LD sound "better" than the DVD counterpart.

(By the way, the TPM DVD was about 10db LOWER in volume than the LD)

Peace.....

[tomdkat]

Originally posted by Oscar Antonio M
Ok i want to remark all the differences i have heard in DTS tracks vs. DD in my DTS DVD´s.

Is volume difference a valid comparison criterion? Can't you adjust the master volume for each DVD to present them at the same volume?

Just because one audio track is recorded at ONE volume which is different than the other is a mastering issue and doesn't have any bearing on what the format is doing with the sound material it has encoded.

In other words, if Gladiator dts audio was 6db LOUDER than the DD audio, then turning the DD audio UP 6db should make for a more accurate comparison as you can focus more on the dynamics of the audio format itself and not be distracted by volume levels.

I was writing MY book at the time you were writing your message, so I had no idea you even mentioned volume levels until now...

Peace.....

[Oscar Antonio M]

Thats exactly what i did Tomdkat.

Oh i know this is out of topic, but what is better?
A Yamaha 6.1 receiver with JBL speakers or a whole HT system in a box with THX encoding.

Just want to know.

[mighty mint]

I was not going to respond to this thread because I believe that you are totally right tomdkat when you say that it really is preference to how it sounds to your ears. I have always found that DD is very directional...sounds coming out of each speaker clearly defined but I prefer the sound field that DTS provides which is more seamless on my system. And that could be another point that one takes into consideration, system set up. I find that sound fields that my amp provides are handled well by DD but I prefer no DSP on my DTS. I like it the way that the DVD has provided the sound and prefer it to be unenhanced. In regards to systems, maybe a person with an 8 or 10 inch sub can't really tell the difference between the deeper bass in DTS vs DD. I really couldn't until I had the 12 and then....heaven! Just my humble thoughts

[tomdkat]

Originally posted by mighty mint
I was not going to respond to this thread because I believe that you are totally right tomdkat when you say that it really is preference to how it sounds to your ears.

Dude... no need to be shy to post your views... I'm certainly glad you did! My main intent was to give this everlasting debate a more "permanent" home since the other threads will "drift off" as other messages are posted.

HT setup DOES play a part, as well as the acoutics of the room in having an impact on how the various sounds sound to you. Having a LARGE sub DOES help with deep bass, but I think having quality speakers should be the ultimate goal. Having subs that provide deep, rich, accurate (whatever that means) bass will help you become part of the action.

It's hard to describe how sounds "sound" using words, especially when describing surround sound but I WILL say that I don't think volume is really a "value added" part of the discussion.

Also, how about those who find dts too overbearing or just "too much to handle"? They would probably favor DD over dts since the DD audio won't blow their ears out. Does this mean DD is "better" than dts? Does this even factor into the techincal debate at all?

I think it would be great to have a DD vs dts audio comparison event, like the audio cable comparison event we had at Audio F/X in Sacramento. Get some DVDs like U-571, Gladiator, and T2:UE and do "blind" DD and dts tests to see if we can actually hear a difference and see which one we tend to favor the most frequently....

Should be a fun event...

Peace....

[Ruined]

Originally posted by tomdkat
He just preferred the "sound stage" presented by the DD audio. The sound that came from the front speakers didn't sound like it was coming from any particular speaker, but from the front and he liked that. With the dts audio, the dialogue (basically reporting how busted the sub was) came distinctly from the center speaker. With the DD audio, this sound seemed to come from the front, but didn't sound as distinctly from the center channel.

What he was hearing was Dolby's channel combination over 15khz at 448kbps (or over 10khz at 384kbps). Technically, this isn't a good thing, but in this case, he preferred the less accurate version over the more accurate version. This is a very possible outcome of a test, and perhaps with this person he will prefer DD in general if he does not like sound coming just from the center (though this would probably be remedied with a better center channel, or maybe even properly calibrated volume levels and delay times).

Does this mean HE thinks DD is "better" than dts? Probably... does this mean DD *is* "better" than dts? Probably not. Just because I like dts audio over DD, why must everyone around me also have the same preference?

When I debate about DD vs DTS, and which is "better", I usually talk about which is more accurate. Everyone around you might like Full Frame or Pan & Scan better than OAR Widescreen, but wouldn't you say OAR Widescreen is "better" or "more accurate"? So, it's not that its bad for him to like DD better, but its okay to explain the advantages of the DTS soundtrack, and what the differences he was hearing were likely attributed to.

Like IndyPhantom indicated, dts can sometime be "overbearing" in the home environment, something the THX processing specifically tries to address.

The only way DTS is more overbearing than Dolby Digital is that it starts out at the master's original volume level, instead of several decibals lower than the masters volume level like DD (due to DD dialog normalization). In addition, DTS soundtracks are fully discrete and have unmodified LFE channels so they may give your speakers more of a workout.

Well, for one the highs (like when the archers where shooting the bows) were much higher, and sharper WITHOUT THX processing than WITH THX processing.

This is due to THX's Re-Equalization circuit which rolls off high frequencies (in case you were unaware), and is generally not desirable these days since studios Re-Eq home mixes before encoding them, and applying a THX Re-Eq at home would essentially be rolling off frequencies that shouldn't be rolled off.

[tomdkat]

Originally posted by Ruined
or maybe even properly calibrated volume levels and delay times

Yeah, this is something I started out doing once and never quite finished the job so I set the settings BACK to the original ones. This was BEFORE I conducted the test I described.

[b]Everyone around you might like Full Frame or Pan & Scan better than OAR Widescreen, but wouldn't you say OAR Widescreen is "better" or "more accurate"?[/q]

Well, I wish this were true but I'm sure there are TONS of people who would say P&S is "better" than OAR because their entire screen is filled, which I think helps to start arguments or debates as "those in the know" try to "educate" the P&S advocate.

So, it's not that its bad for him to like DD better, but its okay to explain the advantages of the DTS soundtrack, and what the differences he was hearing were likely attributed to.

I tend to like the word "differences" more than "advantages" since the latter tends to be more argumentative...

The only way DTS is more overbearing than Dolby Digital is that it starts out at the master's original volume level, instead of several decibals lower than the masters volume level like DD (due to DD dialog normalization).

Given being "overbearing" is one's perception, I think there can be other qualities besides volume that contribute to this feeling. For example, the high frequencies that can be piercing to someone if they have sensitive ears can be problematic even if the volume is not "too loud".

In addition, DTS soundtracks are fully discrete and have unmodified LFE channels so they may give your speakers more of a workout.

I don't remember if you ahve already said anything in your previous posts, but I've been reading in that thread over on AVS Forum that dts gets its LFE signal (for lack of better term) from the rear surrounds. If this is the case, how can you use the term "fully discrete"? Or maybe its the LFE frequencies come the rear surrounds. (I was reading this last Friday which is why I brought it up).

This is due to THX's Re-Equalization circuit which rolls off high frequencies (in case you were unaware), and is generally not desirable these days since studios Re-Eq home mixes before encoding them, and applying a THX Re-Eq at home would essentially be rolling off frequencies that shouldn't be rolled off.

Well, I can't really agree with you on that because the question then becomes which party "understands" the Home Theater environment more? The studio or THX? If the studio Re-Eq's an audio mix targeting the home, why assume they got it right? Conversely, how can one assume THX isn't doing "too much" processing and actually detracting from the audio?

I would be curious to hear how THX Ultra 2 processing differs from THX Ultra AND I would be curious to see which audio people found more agreeable, DD or dts audio WITH or WITHOUT THX processing.

(Yup, I knew about the "rolling off the highs" as part of the THX processing... )

Peace......

[Ruined]

Originally posted by tomdkat
I don't remember if you ahve already said anything in your previous posts, but I've been reading in that thread over on AVS Forum that dts gets its LFE signal (for lack of better term) from the rear surrounds. If this is the case, how can you use the term "fully discrete"? Or maybe its the LFE frequencies come the rear surrounds. (I was reading this last Friday which is why I brought it up).

This is how Theatrical DTS works, not Home DTS; they are two completely different codecs. Home DTS is a much more advanced codec and is a 100% discrete in all channels, while theatrical DTS is borderline discrete like theatrical and home DD.

If the studio Re-Eq's an audio mix targeting the home, why assume they got it right? Conversely, how can one assume THX isn't doing "too much" processing and actually detracting from the audio?

You can't "know" for sure. But then again, you can't do comparisons before each and every movie you watch, then remember the proper THX setting for each and every movie when you want to watch them again. Being that movie studios have been Re-Eqing mixes since before the advent of DVD, it would be an intelligent assumption that most DVDs are re-eq'd. Yes, some may not be properly re-eq'd, but odds are most are, so without going into comparison insanity and just enjoying the movie, the best option would probably be to watch without THX.

I would be curious to hear how THX Ultra 2 processing differs from THX Ultra AND I would be curious to see which audio people found more agreeable, DD or dts audio WITH or WITHOUT THX processing.

THX Ultra vs. THX Ultra 2 is something I don't know the answer to. But, personally I never use THX on my THX Ultra certified preamp/power amp combo, as the DSP mode (which is essentially all THX is) seems to harm the signal more than it helps it from my listening tests, muddling both the high frequencies and the surround field.

[mighty mint]

I have to agree with Ruined, that when I have heard THX being demoed for me, I did not like the sonic result produced. I also find it hard to believe that people find DTS more overbearing than DD when I have found the complete opposite. I have a great sub and what I consider to be quality speakers (Mirage) so volume doesn't play a huge part in compromising how the movies sound on my system. There is clarity at low and high volumes, often times I find the DTS to be lower in volume on a DVD than DD. I have my system set to sound the best at higher volumes to get the most dynamic sound, so needless to say, I crank up the DTS pretty good without compromising quality of sound. DD I find breaks down at higher volumes and the quality of the timber is no longer present.

Ruined, what type of speakers are you running? Are they THX certified?

[tomdkat]

Originally posted by Ruined
This is how Theatrical DTS works, not Home DTS; they are two completely different codecs. Home DTS is a much more advanced codec and is a 100% discrete in all channels, while theatrical DTS is borderline discrete like theatrical and home DD.

Thanks for the clarification.

Being that movie studios have been Re-Eqing mixes since before the advent of DVD, it would be an intelligent assumption that most DVDs are re-eq'd. Yes, some may not be properly re-eq'd, but odds are most are, so without going into comparison insanity and just enjoying the movie, the best option would probably be to watch without THX.

Sorry... can't go with you there.... Jurassic Park (dts) was a prime example of how a DVD audio "mistake" can make it to the masses and you would think a DVD like "Jurassic Park" would be a "flagship" DVD.... I guess we'll just have to disagree on this point.

as the DSP mode (which is essentially all THX is) seems to harm the signal more than it helps it from my listening tests, muddling both the high frequencies and the surround field.

I really haven't decided if I like the THX processing enough to use it exclusively, like some do. I tend to watch some DVDs/LDs with it on and others with it off. I CAN hear a difference in the audio, but not enough in the "surround field" (if any) to make me feel on way or the other about it.

Outside of trimming off the piercing highs (which I'm not opposed to), I can't hear blatantly significant differences in how the audio sounds with THX processing enabled vs it being disabled.

The MAIN reason why I brought up THX processing is that can have an impact on the characteristics that people might try to use to justify their position.

Peace...

[tomdkat]

Originally posted by mighty mint
I also find it hard to believe that people find DTS more overbearing than DD when I have found the complete opposite. I have a great sub and what I consider to be quality speakers (Mirage) so volume doesn't play a huge part in compromising how the movies sound on my system.

It's VERY easy to believe... Not everyone likes hearing piercing highs that hurt their ears, especially if they have sensitive ears.

For example, my dad was over a couple of weeks ago and we watched Black Hawk Down. I turned out all of the lights to have more of a "theater" effect and he asked that I turn a soft light on because his eyes were sensitive to the bright screen of my 57" TV. Plus, he tried to sit as FAR away as possible.

If you like getting your ear blown out, then you probably love what a maximum bitrate dts audio track can do. However, not everyone is like that so I think to not believe that people can find dts to be overbearing at times is somewhat closed minded.

Don't get me wrong... I'm a BIG fan of dts and LOVE having the option to enjoy either audio track when I watch the movies I love.

As for your great sub, I HAVE found at least one instance where I heard (or felt) more LFE bass w/ THX processing enabled than with it off... Of course, we all must take our HT gear into consideration when making these audio format comparisons and sometimes the best "techincal" solution isn't always the "best" practical solution.

The funny thing is, I don't think this is a debate that will EVER be resolved since even the "experts" dispute the "facts" which you would think are objective... Still, I find it fascinating to read....

Peace.....

[Oscar Antonio M]

I dont like using extra processing (Digital Cinema Sound (A,B and C) mostly because the soundfiled sounds fake.

And because the sound is not placed properly where it should be.

[Ruined]

Originally posted by mighty mint
Ruined, what type of speakers are you running? Are they THX certified?

My mains are PSB Stratus Goldi speakers, my center channel is a PSB Stratus C6i, and my surrounds are PSB Stratus Mini speakers. I also had two Bag End Infrasub 18 subwoofers which I sold when I moved into my apartment. Once I move into a house (someday), I plan to repurchase them. And hell no, I don't have THX certified speakers. THX certified speakers have a much-reduced verticle dispersion to "reduce ceiling and floor" reflections according to THX, but in reality this destroys the soundstage especially when listening to music. Ceiling and floor reflections aren't a problem if your room is designed properly.

[mighty mint]

You have to admit Tomdkat that while the first edition of Jurassic P DTS was a huge let down, they more than made up for it with the new repressing! It totally is a true flagship DVD now. According to the Universal office in Canada, I was the first or second person in all of Canada to get the new repressed version and I couldn't believe the difference (neither could my windows!)

In regards to THX speakers, Ruined, I was told that in order to maximize the true THX sound field, one needed to have THX certified speakers. Do you know if this is true or just another way to make the consumer pay more money for a stamp on a speaker? Awesome system by the way no wonder you had to ditch the subs when you moved into the apartment!

[tomdkat]

Originally posted by mighty mint
You have to admit Tomdkat that while the first edition of Jurassic P DTS was a huge let down, they more than made up for it with the new repressing!

I have not heard the new version, but I'm not surprised that it's much improved. I heard they used the laserdisc master for the new pressing. My main point was the studios could do just as a great a job of screwing up a DVD as anyone else so assuming they "know" how to properly make a DVD audio track mix for the home about as much as THX does.....

In regards to THX speakers, Ruined, I was told that in order to maximize the true THX sound field, one needed to have THX certified speakers. Do you know if this is true or just another way to make the consumer pay more money for a stamp on a speaker?

I don't think it's true because when I tell my receiver I have THX speakers connected, it "knows" what levels to set for various things, like crossover network etc, based on THX specs.

I HAVE heard of a case where a THX Ultra certified A?V receiver could NOT drive THX speakers at 4 ohms, even though the THX spec states all THX certified hardware will interoperate with each other. The person *could* have connected his speakers, but Pioneer told him his receiver would NOT push his speakers at 4 ohms and if he tried, they would NOT support any problems that resulted.

Peace.....

[mighty mint]

Interesting to know

[Ruined]

Originally posted by mighty mint
In regards to THX speakers, Ruined, I was told that in order to maximize the true THX sound field, one needed to have THX certified speakers. Do you know if this is true or just another way to make the consumer pay more money for a stamp on a speaker?

The only thing using THX speakers maximizes is the size of THX's income, along with the inaccuaracy of your sound.

In effect, there are simply three things you need for a THX speaker system:

1. The system must be able to handle a moderate amount of power

2. The front speakers in the system must have a diminished verticle dispersion to reduce ceiling and floor reflections.

3. The surround speakers must be dipolar, bipolar, or tripolar in order to increase the ambience of the surround field.

#1 is rather useless, because any decent speaker should be able to handle a moderate amount of power.

#2 actually makes the soundfield less realistic, especially for music, and is really only useful in a poorly designed home theater room (which can be fixed in better ways than limiting the dispersion of your speakers, such as adding carpeting, sound diffusers, etc)

#3 is completely unnecessary and actually damaging to the surround field with the advent of 5.1 sound. The best surround field in a standard room is achieved by placing monopolar (standard direct firing speakers) bookshelf speakers on opposing side walls facing each other, 10 degrees behind the listening position, and raised 6 to 8 feet off the ground. Dipolar/Bipolar/Tripolars were used back when ProLogic was the only surround format because these speakers created a more "stereo" sounding surround field with the mono-surround field Prologic format. They do so by bouncing the sound all over the room before it reaches your ear. These days, a properly setup 5.1 system with monopolar surrounds will sound superior, as the surround field is already stereo, and it does not have the degraded quality and convoluted sound that dipolar/bipolar/tripolar speakers present.

So in essence, THX speakers will likely do more damage than good to your system compared to similar quality non-THX speakers.

[airjosh]

#3 is completely unnecessary and actually damaging to the surround field with the advent of 5.1 sound. The best surround field in a standard room is achieved by placing monopolar (standard direct firing speakers) bookshelf speakers on opposing side walls facing each other, 10 degrees behind the listening position, and raised 6 to 8 feet off the ground. Dipolar/Bipolar/Tripolars were used back when ProLogic was the only surround format because these speakers created a more "stereo" sounding surround field with the mono-surround field Prologic format. They do so by bouncing the sound all over the room before it reaches your ear.

A standard room is a perfectly square box with 8 foot ceilings. Not very many people's rooms are exact or "standard". All of that changes in the real world. Again, the math can only take you so far, you need to focus more on the implementation.

Dipolar speakers were created to sit inline with the listening postion where they create a null space (the speakers are out of phase). This was done to create a more open, enveloping surround field that is not localized to one side or the other. In some ways this may defeat the purpose of discreet channels, but it certainly was not intended to create a "stereo" surround field. Less localization, not more.

[Ruined]

Originally posted by airjosh


A standard room is a perfectly square box with 8 foot ceilings. Not very many people's rooms are exact or "standard". All of that changes in the real world. Again, the math can only take you so far, you need to focus more on the implementation.

Actually a standard room is simply one that has two side walls where the speakers can be placed equidistant from the center listening position, raised 5-8 feet off the ground. And for the record, a rectangular room is a much, much better acoustical choice of design if you are designing a Home Theater room.

Dipolar speakers were created to sit inline with the listening postion where they create a null space (the speakers are out of phase). This was done to create a more open, enveloping surround field that is not localized to one side or the other. In some ways this may defeat the purpose of discreet channels, but it certainly was not intended to create a "stereo" surround field. Less localization, not more.

Creating a "more open, enveloping surround field" made the mono surround channel of Dolby Pro-Logic sound more expansive (or more "stereo", which is inherently more open and enveloping than mono) than it actually was. If your monopolar direct firing surrounds are placed properly, localization will not be a problem.