Trouble understanding DTS

[cftrock]

Hey guys,
I have a Pioneer XV-HTD510 DVD Home Theater System which features Dolby Digital and DTS decoders.
I've always been under the impression that my system can play DTS soundtracks. I've also read that DTS offers better sound than that of Dolby Digital, so when I buy DVD's I always buy the DTS versions and/or always select the DTS soundtrack as opposed to the Dolby Digital soundtrack. Recently though I have been reading about Digital Audio (SPDIF), DTS equiped receivers and DTS speakers. As you guys can tell by the 1st part of my post, I'm not as up-to-date on my technology nor do I fully understand all the specs that come with DVD players and home theater systems. So my question is, when I choose the DTS soundtrack off the menu screen and play the movie, am I actually hearing the DTS track to its full capacity? Am I just hearing a Dolby Digital track since I don't have the right equipment? I do get the little DTS icon to pop up on my DVD display screen. Do I need any of that equipment or is that equipment only necessary for people who just have stand-alone DVD players?
Sorry for the stupidity but I need to know if I've been living a lie for the last couple of years. Have I not been listening to a real DTS soundtrack since I don't have DTS speakers or because I don't have a DTS equpied reciever?
Any help would be real thankful.

[Hollow Man]

Here's the simple answer. If you are in fact selecting DTS as the audio option from a DVD, and then you in fact hear something through your speakers when you play the DVD, then you are (in fact) listening to the DTS track. If your equipment wasn't capable of playing DTS enabled DVDs, you would hear nothing.

-HM

[snipsnapsappy]

What is a DTS speaker? I have never heard of a DTS speaker. Where did you hear of this? There is no mention of a DTS speaker on the DTS website.

I am sure you are getting your DTS correctly. Have you tried using a Setup disc such as Digital Video Essentials to make sure all of your speakers and electronics are set up properly? That is the best way to know for sure that everything is running properly.

[palebluedot]

On your system, you should be able to play DTS discs with no additional equipment. Using the remote control press the "SURROUND MODE" button until the display says "AUTO". Load in a disc with DTS sound and go to the Sound Options menu on the disc (not on your hardware) and choose the DTS surround option. Start playing the disc and the "dts" logo on the left side of your hardware's display should light up.

[cftrock]

Thanks guys

[Icon769]

1. My old DVD player has a DTS logo on it, yet when I would put a DTS track nothing would sound. Since the player had the DTS logo shouldn't it be able to play? or even with the DTS logo is it missing something?

2. What's the difference in listening to a DTS track with and without a receiver?

[brian]

Originally Posted by Icon769

2. What's the difference in listening to a DTS track with and without a receiver?

You'd have trouble getting sound. That's the main difference -- as far as i know, DTS surround tracks can't be (or usually aren't) downmixed to stereo.

My guess is your old DVD player could simply pass the data to a receiver, or perhaps had a decoder built-in, in which you'd use the 6-channel outputs on the player. Neither of which would really help you in a set-up without a receiver.

[Sword of Whedon]

You'd have trouble getting sound. That's the main difference -- as far as i know, DTS surround tracks can't be (or usually aren't) downmixed to stereo.

My Pioneer VSX-D511 reciever will downmix DTS to stereo.

[brian]

Originally Posted by Sword of Whedon

My Pioneer VSX-D511 reciever will downmix DTS to stereo.

Now that I think of it, my receiver does as well. But, I was answering his question regarding there being no receiver in the question. I don't think a signal will be sent out the L/R stereo outputs, and if it is, what's really the point? (Assuming he's going to be listening through his TV speakers) Really, if you want to listen to a movie in stereo, it's probably just better to listen to the stereo track.

[phpotato]

Also, note that most DVDs now do not have full bitrate DTS.

The titles that have full bitrate DTS usually can't fit both DTS and DD5.1 and commentary track on one disc, so they are "bare bones" discs with only the DTS track.

R1 titles like "The Ring" demonstrate that DTS does not have to be full bitrate to sound really good.

Quality depends on the mastering (quality) process. I'd prefer THX-mastered Dolby to DTS, if given the choice.

[Ruined]

Some quick facts on DTS:

* DTS can be downmixed to stereo, but must be decoded by a DTS decoder first. This is in contrast to Dolby Digital, which can be downmixed within the DVD player first.

* Without a DTS decoder, if you attempt to play a DTS track you will hear nothing or white noise (static). If you select DTS and hear sound, you are hearing DTS.

* DTS has no specifications for speakers AFAIK, but there are THX speakers, which are arguably worse than standard speakers.

* I have found that recently THX mastering is more of a marketing gimmick and less of a quality stamp like it used to be. (Despite owning THX-Ultra gear). However THX's receiver DSP modes may be useful for those who have their gear in an overly harsh room and need a DSP mode to tone down the highs.

* DTS 754kbps (low bitrate) offers a similar sound to 1509kbps (high bitrate). The reason why is because DTS low bitrate has a frequency response range from 3hz - 19khz, while DTS high bitrate has a frequency response range from 3hz - 24khz (or 48 khz if its dts24/96). Either sounds find because we can't hear over ~18.5khz.

* Both bitrates generally sound better than Dolby Digital, which has inferior LFE (usually lags behind mains quite a bit, and often is not the same as the original master due to DPL downmixing concerns - this is often why reviewers find DTS to have stronger bass), plus inferior channel seperation (DD combines channels above 10khz @ 384kbps and above 15khz @ 448kbps - frequencies that are both in the human hearing range. - this is why reviewers find dts surround to often be more "open" or "airy"). A simulation of what the high frequencies could look like is illustrated below. DTS also offers a discrete 6.1 channels to Dolby's discrete 5.1, plus DTS currently offers a maximum of 24bit, 96khz sound compared to Dolby's 24bit/48khz max. The DTS codec is also capable of lossless encoding of up to 8.1 channels at 6000+ mbps, but no piece of hardware or software has used this functionality (with a max of 6.1 24/96 1509kbps on DVD). Dolby's codec offers a maximum of 5.1 channels 24/48 at 640kbps (448 max on DVD) in comparison. DTS also offers offers 2.0 bitrates in the 250kbps - 500kbps range, which can be encoded with the latest DTS encoders. DTS also offers an on-the-fly 500kbps 4.0 software-encoded codec that is used on PS2 for surround sound.

Simulation of possible channel combination effect on high frequencies
Stereo track composite frequency output
Simulation not exact, compression artifacts not considered

NOTE: DTS1509's high frequencies would look similar to the original file

[Sycho]

you said that Dolby digital combines sound about 10kHz 384kbps and 15kHz on 448kbps streams, but you did not mention its ability to separate the sound to goto the correct channel. Lots of people think channel coupling in shity, but they never consider the decoupling, if done properly it will save loads of space without compromising quality, which is the whole point of Dolby Digital.

EDIT: dts half-rate has a high end -3dB point of 15kHz

[Ruined]

Originally Posted by sycho

you said that Dolby digital combines sound about 10kHz 384kbps and 15kHz on 448kbps streams, but you did not mention its ability to separate the sound to goto the correct channel. Lots of people think channel coupling in shity, but they never consider the decoupling, if done properly it will save loads of space without compromising quality, which is the whole point of Dolby Digital.

The DTS codec also supports a similar channel-coupling technology. It is not used by choice of DTS because it produces inferior channel seperation, and DTS for DVD is marketed as a higher-end, higher bitrate sound format - not one that needs to save space. This is why review after review notes DTS' soundfield as more "open" or "airy." (or more "spacial" ) Not just a coincidence, there is actually technology behind it. Since Dolby Digital is marketed as a format to save bits, it needs to utilize the technology to keep its bitrate down. DTS does not. I wouldn't call Dolby's method (which DTS could also employ if they wished - and likely do in PS2's 500kbps 4.0 codec) "shitty," but it certainly does compromise the soundfield in a way that would not be necessary if Dolby had the bitrate of DTS.

EDIT: dts half-rate has a high end -3dB point of 15kHz

That figure has been much improved with modern DTS encoders (your figure is an outdated one from when the very first DTS 754 encoder firmware was released), and DTS 754 encoders now actually produce sound well beyond 20khz. The above graph is a rough model of how much of a dropoff DTS 754 exhibits. The fact that DTS can do so without compromising the discreteness of the channels makes it a superior option to Dolby Digital (especially when combined with DD's LFE problems), so long as you do not need to save bitrate, where DD would be a better option (such as HDTV). For DVD, though, DTS is the way to go.

[Iguana Man]

Originally Posted by Ruined

A simulation of what the high frequencies could look like, when downmixed from 5.1 to a mono channel, is illustrated below.

Hope this isn't a n00b question, but why are the left and right (blue/purple) channels in each graph so different looking ? For some reason I 'think' the left and right channels should appear more identical to one another.... ....

[Ruined]

Originally Posted by Iguana Man

Hope this isn't a n00b question, but why are the left and right (blue/purple) channels in each graph so different looking ? For some reason I 'think' the left and right channels should appear more identical to one another.... ....

BTW, I made an error in the body of the post, its a composite graph of stereo signals (as I stated above the graph), not 5.1 - though a 5.1 graph would look even worse for DD. If you mean in a single graph, the left and right channels were purposely made different in the simulation to illustrate the worst case scenario of DD's channel coupling technology & rolloff vs. the frequency rolloff of DTS 754. Between graphs, the channels' midrange might look slightly different simply because I might have captured the graphs milliseconds apart which could have resulted in slight differences, and even moreso the differences caused by using the filters and mixing to simulate the high-end frequency differences between the two codecs. However the primary differences I was illustrating were not the differences in the channels' midrange, but rather the gaping differences near the high end of the frequency spectrum, so they turned out pretty good.

[Sycho]

but you must admit that Dolby Digital AC3 is a for more advanced codec, ac3 was there Audio Codec 3, and dts in the home is there second codec as a corporation, and now Dolby help produce such things as AAC (Advanced Audio Codec) which can have multichannel audio with really good quality at bit-rates as low as 192kbps, for 5.1!. Also Dolby Labs was been around alot longer than dts, in doing so they have more experience, they was the first to bring surround audio in movies to an affordable level, what has dts done? One KILLER cinema codec (not available in the home), and another that is more confusing to the consumer then most of the electronics (IE dts, dts-ES Matrix, dts-ES Discrete, dts-96/24). Don't get me wrong, I love dts, but only for the discrete Extended Surround, other than that it not worth hunting through meuns to get.

PS: Try this, get a SPL meter, find a part in a movie with Dolby Digital (448kbps) and a dts track, play it with a part with one loud noise on the main channels, record volume on receiver and SPL meter, then do the same thing but for the other track, but set the volume so the sound of the loud noise is the same level as the first track, record volume on receiver. Now playback a part you know on the dts track, change the level according to the SPL meter, play the Dolby Digital track, if the master were the same, you should not notice a difference between the two. For fun, two people should do blind ABX test, so there no unconscious favoring of one or the other track. (Only do this test with 5.1 tracks, no DDEX decoding or dts-ES decoding) This worked for me on Xmen 1.5, X2, Road Trip(belive it or not), Gladiator and a few others. Comparing this way allows you to know right away if the track are from different masters.

[brian]

Originally Posted by sycho

but you must admit that Dolby Digital AC3 is a for more advanced codec, ac3 was there Audio Codec 3, and dts in the home is there second codec as a corporation, and now Dolby help produce such things as AAC (Advanced Audio Codec) which can have multichannel audio with really good quality at bit-rates as low as 192kbps, for 5.1!. Also Dolby Labs was been around alot longer than dts, in doing so they have more experience, they was the first to bring surround audio in movies to an affordable level, what has dts done? One KILLER cinema codec (not available in the home), and another that is more confusing to the consumer then most of the electronics (IE dts, dts-ES Matrix, dts-ES Discrete, dts-96/24). Don't get me wrong, I love dts, but only for the discrete Extended Surround, other than that it not worth hunting through meuns to get.

I'm confused -- none of the following things, including how long Dolby Labs has been around, proves or even suggests that AC3 is a far more advanced codec. It's great that you love the codec or company, but I'm not sure why a company's policy, history, or other codec should have an impact on how we perceive the two codecs in question.

If you haven't already, you should check out this thread. It's an older discussion, and many similar points have been covered there.

Thanks Ruined, for posting those graphs. I'm always interested in seeing some scientific arguments.

[Ruined]

Originally Posted by sycho

but you must admit that Dolby Digital AC3 is a for more advanced codec, ac3 was there Audio Codec 3,and dts in the home is there second codec as a corporation

No, actually the DTS codec is far more advanced than the DD codec. The DTS codec is scalable from 32kbps up to 6000+kbps, can do up to 8.1 channels, 24bit/96khz and lossless encoding. Dolby, on the other hand, can only do a maximum of 640kbps, lossy, 5.1 channels, at 24bit/48khz. DTS has simply chosen to use the "higher end" portion of their codec as their primary encoding choices because that is the main way they were able to make inroads into Dolby's market. If DTS simply offered low bitrates (which they could based on their codec), then there would be no reason for someone to use DTS, and Dolby would have murdered them. Instead, by using the higher bitrate, higher quality portion of their codec, DTS was able to make inroads with the hifi market. Trying to argue that Dolby is more advanced because it has had more revisions is a bit, erm, silly?

and now Dolby help produce such things as AAC (Advanced Audio Codec) which can have multichannel audio with really good quality at bit-rates as low as 192kbps, for 5.1!.

There is no doubting that Dolby has captured the low bitrate market, but DTS does not have to compete with them there. I'm not arguing that Dolby doesn't have a use, it does, and its a great codec. However that doesn't mean it sounds better than DTS - technically, it's significantly worse, and comparisons reflect this. However for something like HDTV, you would want to take the tradeoff for lower bitrate with a sacrifice in sound quality - you wouldn't want DTS taking up all your bandwidth. But on DVD where bandwidth is available, DTS is very welcome.

Also Dolby Labs was been around alot longer than dts, in doing so they have more experience, they was the first to bring surround audio in movies to an affordable level, what has dts done?

DTS brought surround to the movie theaters in a form that required less maintenance and had less dropouts/problems than DD. With DTS, the 5.1 soundtrack was stored on compact discs. With Dolby, the digital information was stored on the film itself (between sprocket holes), and when the film got tattered, the soundtrack would often dropout and revert back to analog, which many probably have experienced in the movie theater (where did the surround go?) DTS brought a solution to the movies that offered more consistent performance, and movie theaters could present a movie without having to worry that the sound would drop out/revert to analog and order new films. Not to mention DTS was the first to bring external triggered events (such as activating strobe lights in a theater during a portion of a movie or a trailer) to movie theater soundtracks.

One KILLER cinema codec (not available in the home),

Actually you have it backwards, DTS' home codec is far superior to their cinema codec. DTS' cinema codec does not have full range surround channels like their home codec, nor does it have the scalibility of their home codec.

and another that is more confusing to the consumer then most of the electronics (IE dts, dts-ES Matrix, dts-ES Discrete, dts-96/24). Don't get me wrong, I love dts, but only for the discrete Extended Surround, other than that it not worth hunting through meuns to get.

Dolby created the problem, not DTS. Since Dolby's codec can't produce a true 6.1 signal, they formed DD5.1 EX, (fake 6.1), which essentially is 5.1 with a prologic decoder on top of the surround channels. Blame Dolby and THX for the naming misnomer, not DTS, as they were the first to start adding suffixes.

PS: Try this, get a SPL meter, find a part in a movie with Dolby Digital (448kbps) and a dts track, play it with a part with one loud noise on the main channels, record volume on receiver and SPL meter, then do the same thing but for the other track, but set the volume so the sound of the loud noise is the same level as the first track, record volume on receiver. Now playback a part you know on the dts track, change the level according to the SPL meter, play the Dolby Digital track, if the master were the same, you should not notice a difference between the two. For fun, two people should do blind ABX test, so there no unconscious favoring of one or the other track. (Only do this test with 5.1 tracks, no DDEX decoding or dts-ES decoding) This worked for me on Xmen 1.5, X2, Road Trip(belive it or not), Gladiator and a few others. Comparing this way allows you to know right away if the track are from different masters.

Actually you should notice a difference between the two on demanding material - even if both Dolby and DTS produced zero compression artifacts, the way they handle very high and very low frequencies to get zero artifacts is extremely different, and DTS simply does it better and more accurately. Many Dolby Digital DVDs have part of the LFE removed and mixed into the mains in order to get better Prologic compatibility, leaving a hampered LFE (that lags behind the mains, no less), and high frequency channel combination on DD soundtracks was already discussed. It's no mystery that these mixing choices cause a difference in sound, as the overwhelming majority of A/B DD/DTS reviews either show a tie or DTS on top. It is very rare that Dolby is the victor in A/B comparison. While trends are far from scientific, they give you a general idea of which sounds better, and in general, that is DTS.

That being said, not all have the best quality equipment, speakers, room, or even the discerning ear to tell the difference. If you use a $500 5.1 setup, I wouldn't be surprised if one couldn't tell the difference between DD and DTS. Likewise, the sensitivity of each individual's hearing varies from person to person, and hence one person could hear a difference and another not. In addition, the source material makes a difference as well - trying to find differences in "Road Trip" is probably a lost cause, as its simply not a movie that was designed with an impressive soundtrack as a priority.

If you are inferring that seeing if volume between tracks can determine whether the same master was used for each track (often its not), doing so is fruitless. Dolby's Dialog Normalization brings the sound level of the material several decibals below the original master, while the DTS codec plays back at the original master volume level. DTS tracks will generally be louder than DD tracks simply because they are playing back at reference level, while DD tracks are 5-6db below reference due to dialnorm. This might be useful for HDTV to keep an overall constant volume level from channel to channel, but for DVD it simply makes a for a less accurate presentation of the master with more unnecessary processing. In other words, DTS is presenting the most accurate master volume level as well.

In the end, DTS just presents a more pure representation of the master with less processing and mixing than Dolby Digital - even if a Dolby encoding has zero compression artifacts, it is still hampered by its low and high frequency mixing and encoding choices (due both to DPL backwards compatibility and DD's lower bitrate), giving DTS the clear, and most accurate, edge.

[Iguana Man]

Originally Posted by sycho

but you must admit that Dolby Digital AC3 is a for more advanced codec, ac3 was there Audio Codec 3, and dts in the home is there second codec as a corporation,

I tend to think improvements are usually made, in as you say, "there second" attempts, which in this case according to you would be DTS. While I admit I have heard many outstanding DD5.1 tracks, I tend to find that 8 or 9 times outta 10, DTS sounds better to me. Either way, they both sound good.

Originally Posted by sycho

Don't get me wrong, I love dts, but only for the discrete Extended Surround, other than that it not worth hunting through meuns to get.

Well then, you may want to change that sig! (and the DTS is usually right above the DD5.1 option in the main menu which aint to hard to find! :p

[Sycho]

all things being equal, no sweetening, like on most dts tracks, if a dts and Dolby track exists, (DD 448kbps, and dts 1538kbps) they should sound the same, which some do, if some of them sound the same, wouldn't that mean the Dolby is more advanced. Let me define it the way I am using it, both Dolby and dts have a codec, both are lossy, both have 5.1, only one is a standard, both will reconstruct the 5.1 speaker rig, but, one will take up 4x the room, so which one holds the same information using less space.

The main reason most of you say that dts is better is because that they have sweetening done the the high end (boosted bout 3dB) and the surrounds a loud on top of that (the full range of the surround channels boosted by 3dB), usually, when people say that they don't notice a difference, thats because it was encoded properly

Just think about it, and ignore everything you have ever heard about AC3 and dts, they both do the same thing, they both throw away so information, one can do 5.1 at 448kbps and the other at 1538kbps, for example which do you use, Mpeg Audio 1 layer II or layer III, layer II has high bit-rates, but layer III will provide better compression when using M/S coding, which is how Dolby Digital works, dts codes all channel separately, correct? Dolby Digital will code the sound buy combining the common sounds (think L+R and L-R), abd then decode it ( [L+R]+[L-R]=L and [L+R]-[L-R]=R)

@Iguana Man
Before you criticize my signature, actually take time to read and think about what it says, and I don't like to go through menus, I just play the movie

@Ruined
dts's cinema codec is better because if will provide a better sound than any of the codec mentioned in this thread, it uses only ADPCM compression, which uses the differences between samples to compresses sound, by far one of the best compressors if used properly. Scalability has nothing to do with a codec being better.

@brian
Dolby Mono
Dolby A Noise Reduction
Dolby Stereo
Dolby 70mm Stereo (5-track)
Dolby B Noise Reduction
Dolby C Noise Reduction
Dolby Surround
Dolby HX Pro
Dolby SR Stereo
Dolby Surround Prologic
Dolby Stereo Digital (aka Dolby Digital)
Dolby Digital EX Extended Surround
Dolby Surround Prologic II
Dolby Surround Prologic IIx

[Ruined]

Originally Posted by sycho

all things being equal, no sweetening, like on most dts tracks, if a dts and Dolby track exists, (DD 448kbps, and dts 1538kbps) they should sound the same, which some do, if some of them sound the same, wouldn't that mean the Dolby is more advanced. Let me define it the way I am using it, both Dolby and dts have a codec, both are lossy, both have 5.1, only one is a standard, both will reconstruct the 5.1 speaker rig, but, one will take up 4x the room, so which one holds the same information using less space.

Ahh, so MP3, OGG, and WMA all sound the same also?

The main reason most of you say that dts is better is because that they have sweetening done the the high end (boosted bout 3dB) and the surrounds a loud on top of that (the full range of the surround channels boosted by 3dB), usually, when people say that they don't notice a difference, thats because it was encoded properly

DTS has never "sweetened" a mix. There were few cases back in the laserdisc days where DTS was sent cinema masters by the studios that were not attenuated and told it was a home master, and sent back to the studio an encoding of what they were sent. This resulted in some Laserdiscs having +3db in the surrounds and +10db in the LFE; this was the studios' errors, not DTS'. There has not been any DTS DVD released that has any attenuation errors or channel volume level errors (with the exception of Jurassic Park, which also had the same problems in the DD version, and a corrected DTS version was released). I can name several Dolby ones, though. DTS does not even do the encoding anymore. Please do not make up things. (this argument died back in 1997)

Just think about it, and ignore everything you have ever heard about AC3 and dts, they both do the same thing, they both throw away so information, one can do 5.1 at 448kbps and the other at 1538kbps, for example which do you use, Mpeg Audio 1 layer II or layer III, layer II has high bit-rates, but layer III will provide better compression when using M/S coding, which is how Dolby Digital works, dts codes all channel separately, correct? Dolby Digital will code the sound buy combining the common sounds (think L+R and L-R), abd then decode it ( [L+R]+[L-R]=L and [L+R]-[L-R]=R)

MP3, OGG, and WMA all sound different and do the same thing. Same with DD and DTS. Your logic is very flawed.

@Ruined
dts's cinema codec is better because if will provide a better sound than any of the codec mentioned in this thread, it uses only ADPCM compression, which uses the differences between samples to compresses sound, by far one of the best compressors if used properly. Scalability has nothing to do with a codec being better.

DTS Home uses sub-band ADPCM coding just like DTS cinema's codec that you are touting and all five main channels are full-range, unlike DTS Cinema which does not have full-range surround channels. DTS Home does not support some of the features that DTS Cinema does, such as triggered events and data cues to move on to the next CD, however these are features that would not be useful for the home environment and are more suited for the cinema environment.

@brian
Dolby Mono
Dolby A Noise Reduction
Dolby Stereo
Dolby 70mm Stereo (5-track)
Dolby B Noise Reduction
Dolby C Noise Reduction
Dolby Surround
Dolby HX Pro
Dolby SR Stereo
Dolby Surround Prologic
Dolby Stereo Digital (aka Dolby Digital)
Dolby Digital EX Extended Surround
Dolby Surround Prologic II
Dolby Surround Prologic IIx

You forgot Dolby Headphone

[Iguana Man]

Originally Posted by sycho

@Iguana Man
Before you criticize my signature, actually take time to read and think about what it says, and I don't like to go through menus, I just play the movie

Dude, in my book a " " doesn't mean "criticize" - however, I may have pushed it a bit and for that, all I can say is .... ....

I read your sig again (and again ) and I see I did fail to understand the meaning behind it. It is very clear that DD5.1 is better..."period".

My bad