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icarus
01-31-2007, 09:55 PM
With the recent thread about THX, I decided to set up a thread to discuss the different formats. To attempt to clear up what the differences are.

Dolby Pro Logic
Dolby Pro Logic provides left, center, and right front channels and a single surround channel. However, Pro Logic is a "matrix" format with a certain amount of channel-to-channel leakage. This flaw is not audible under most circumstances. Pro Logic is still used to decode the audio Portions of Many Videotapes and NTSC TV broadcasts.

Dolby Pro Logic II
This is a very sophisticated update of Pro Logic's matrix approach to surround sound. It adds stereo surround capabilties so it can call it a 5.0 faormat and it features greater channel seperation. Pro Logic II includes two modes, both a movie, and a music mode, thus making it a very suitable surround application.

Dolby Digital
This is the original 5.1 format. It is discrete in that channel-to-channel seperation is in total, an important consideration when trying to locate the origin of specific portions of movie sountracks. Dolby Digital accounts for the majority of all multi-channel software available today.

DTS
This Dolby competitor initially promised superior sound because it used less digital
compression to convey sound from the dubbing stage (where movie soundtracks are made) to your home. Recent comparisons have proven these claims difficult to defend, especially with DVD, which uses a more compressed version of the original DTS format.

Dolby Digital EX
A Dolby Digital variant, EX adds a third surround channel to Dolby
Digital’s two. This extra channel (called Center Back or Surround Rear, depending on who
you ask) is not discrete but is matrixed onto the stereo surround information. Technically,
that makes it a “5.1+” format but is commonly – though erroneously – referred to as a
“6.1” format. It gives the sound engineer a more complete audio palette from which to
construct a convincing sense of directionality for surround information. You need Dolby
Digital EX encoded software, an EX decoder, and an extra rear speaker (or speaker pair)
to enjoy the sonic benefits.

THX
It’s not a surround sound format at all even though it is often confused with one.
THX is a set of standards and technologies designed to make a home theater sound more
like a movie theater. As such, it deals with audio signals only after they’ve already been
decoded. While generally accepted as legitimate for movie soundtrack reproduction, THX
has inspired some controversy in audiophile circles where it is said to compromise music
reproduction.


So I think I've got it all pretty well covered, and I hope that this is very informative, and if any of this is worng please correct me.

elapsed
01-31-2007, 10:22 PM
Thanks for the informative post :)

But.. what about newer formats such as Dolby Pro Logic IIx, Dolby Digital Plus, Dolby TrueHD, DTS-ES, and DTS-HD?

PeruvianSkies
01-31-2007, 10:22 PM
You may want to include things such as SDDS or receiver settings like Neo:6.

icarus
01-31-2007, 11:13 PM
Oh fuddle Duddle, I knew I forgot a bunch...

icarus
01-31-2007, 11:18 PM
Since im lazy and don't feel like typing out another 10 or so formats here is a link i found that should cover them all. Should, some fo you out there will probably just find more that aren't this list so...
http://www.hometheaterhifi.com/volume_11_1/feature-prologic-iix-3-2004.html

Dusty Chalk
02-01-2007, 12:09 AM
What about the 24/96 variant of DTS, where does that fit in? Isn't that technically another format?

icarus
02-01-2007, 12:12 AM
now your just trying to piss me off here Dusty... Admit it.. pretty soon you'll be making up formats just to drive me insnae trying to find info about them!!!

Dusty Chalk
02-01-2007, 12:14 AM
No, look, it's even got it's own logo:

http://www.commentcamarche.net/audio/images/dts-24-96.png

PeruvianSkies
02-01-2007, 01:21 AM
Two things that I found funny....

1. the person who wrote that page for the sound format link that you provided is written by Brian FLORIAN and

2. the person who started this forum is getting upset because the rest of us are chiming in with completions to their original post, which strikes me odd because if you don't want people to add anything, than make the list complete in the first place.

icarus
02-01-2007, 08:59 AM
I appologize if i came across as a pissed off that dusty was adding new formats, I was actually trying to be sarcastic, even though it came accross that I was just an ass. I started this thread for people to fill in the blanks of formats that i missed. so i totally encourage it.

actually that is pretty humourous that the link was written by florian i never noticed it before.

DTS 96/24
The DTS coding system has a “core + extension” structure. The “core” represents the DTS data as has been known since the first home decoders. The “extension” can carry data for future applications or enhancements of any sort. All DTS decoders recognize and use the core data. Basic decoders ignore the extension data, while advanced decoders can make use of it. The extension for DTS 96/24 carries the additional spectral data added by 96-kHz sampling.DTS 96/24 decoders read both core and extension and reproduce the extended spectrum. The data rate for 96/24 is 1.536Mbit/s, the higher of the two DTS rates presently used.

Dusty Chalk
02-01-2007, 10:16 AM
Well being that I'm the same way -- both sarcastic and "ass" -- I got it that you were just expressing your frustration in a humorous fashion.

icarus
02-01-2007, 10:26 AM
glad to hear im not the only sarcastic ass on this forum. Together we shall rise up and conquer middle earth!!!!
sorry thats my Lord of the ring turrets acting up again one ring to rule them all!

GMichael
02-01-2007, 01:35 PM
glad to hear im not the only sarcastic ass on this forum. Together we shall rise up and conquer middle earth!!!!
sorry thats my Lord of the ring turrets acting up again one ring to rule them all!

A cool start to an informative thread.
The only sarcastic @ss? I think that we may be the majority here.

PeruvianSkies
02-01-2007, 01:51 PM
It might also be helpful to distinguish the difference for some between discrete sound and matrixed sound, there seems to be alot of questions pertaining to people using a middle rear channel and the differences between DTS-ES (Matrix) and (Discrete) also the case with Dolby Digital EX sound.

icarus
02-01-2007, 03:09 PM
Matrixed sound
to figure out how matrix sound works check out this link http://www.informit.com/articles/article.asp?p=341486&rl=1

Discrete Sound
Check out this link for Discrete Sound http://www.informit.com/articles/article.asp?p=341486&seqNum=2&rl=1

Rock789
02-01-2007, 07:16 PM
You may want to include things such as SDDS or receiver settings like Neo:6.

is SDDS 8 ch surround? and are there any dvd's (or newer formats) using sdds?
on that note, any players and pre/pro's able to do sdds?
thanks,
Mike

edit:
http://www.sdds.com/

PeruvianSkies
02-02-2007, 12:29 PM
SDDS is strictly a theater format for sound and it is 8-channel of sound. Not many features or theaters use this, but if you get a chance to see a film this way, be sure to do so!

Woochifer
02-02-2007, 01:25 PM
is SDDS 8 ch surround? and are there any dvd's (or newer formats) using sdds?
on that note, any players and pre/pro's able to do sdds?
thanks,
Mike

edit:
http://www.sdds.com/

SDDS is basically an orphaned theatrical format. Many theaters are still equipped with the SDDS decoders and theatrical prints from the major studios still include the SDDS optical code, but the Sony division that marketed and developed SDDS no longer exists. Most theaters and movies supporting SDDS use the six-channel version. The 8-channel SDDS-8 format is only used on a select few movies, and requires five screen speakers which very few theaters use nowadays.

And this format/configuration probably won't ever come to home theater. Even though the new Dolby Digital Plus, Dolby TrueHD, and DTS-HD Master formats can now support a discrete eight-channel 7.1 configuration, soundtracks that were produced in SDDS-8 still cannot be directly transferred for home use without remixing. This is because the 7.1 configuration for home theater calls for three channels up front, four surround channels, and the LFE channel. The SDDS-8 configuration entails five channels up front, and two surround channels, plus the subwoofer track.

PeruvianSkies
02-02-2007, 02:23 PM
Which is exactly why the 8Track SDDS of STARSHIP TROOPERS just doesn't sound the same in DTS 5.1, I'll be curious what the Blu ray sounds like.