Cunhambebe, I'd be looking at the Dolby pages. Far as I know, what you're asking isn't doable in DVDA or AC3.

Thank you very much for helping, Spot. You are such a real excellent professional and your job has helped so many users around here. It's nice to know we can count on people like you. By the way, I was just thinking about encoding a new project as 6.1 or even 7.1. I've already searched for answers on the web and just found out that Dolby Surround EX is not the "real" 6.1, but an enhanced version of our old friend, Dolby 5.1. So I really wonder if there's a codec or piece of software that let us encode AC-3 files as 6.1 or 7.1. I really can't find that topic I had seen here before - it was exactly about this subject. Thanks again.

:( - ?????? no one? nobody? What happened?

you will need a EX-EU4 Dolby Surround EX Encoder ($3000) and a DP569 Multichannel Dolby Digital Encoder($5550 i think) and a cable kit ($400) and option of a dolby pre-proccessor (DP570 Multichannel Audio Tool ($6500)

http://www.dolby.com/assets/pdf/tech_library/21_Encoding.DVD.pdf <--- same as this but add the EX encoder into the mix ..

if you mean Dolby Digital Plus (7.1 and up) ... wait for NAB for some announcements -- i think Nuendo 3 Production will support this (at some point)

SONAR 4 also supports 7.1 , but i dont know its encoding ...

you can also go with 96 kHz and 6.1-channel discrete DTS-ES - which right now is cheaper than dolby solutions ... Peter Gabriel is the first artist to use DTS Pro Series 6.1 Surround Encoder on a commercial project. At his Real World Studios, he is currently using it to encode the DVD music title Play: Videos,which was released in the fall. All surround tracks on Play were encoded in DTS 96/24.


http://www.surroundpro.com has a lot of good info on these subjects ...

btw -- dolby will suggest you also buy the decoders for the above - so add another ~$7000

Thanks to all who took time to respond...It's a lot of money ;)

Cunhambebe, I'm sorry I haven't had time to look at this forum much recently. So, I hope I'm not too late...

Let me hit some basics - AC3, which has the trademarked name of "Dolby Digital" has a number of variants. The 6.1 version is called Dolby Digital EX. Dolby Digital EX has 5.1 discrete encoded channels and 1 (rear center) matrix encoded channel. Many receivers use the two rear side channels to first directionalize the sound and make this a 7.1-channel output.

DTS has a 6.1 channel output called DTS-ES, which creates 6.1 discrete channels.

The good news is that to tell an A/V receiver that it is receiving a Dolby Digital EX signal only requires the setting of a flag. That flag is supported in Vegas 5. You'll have to create a new audio setting under AC3 and enable the flag.

Many A/V receivers will output the rear center channel even if the flag is not set in the audio stream.

Having said that, you also want to make sure that your surround audio is something that will be decoded properly by a Dolby Digital EX decoder. For the DVD I just finished, the surround channels had crowd noise and this was a natural for EX. Keep in mind that any mono signal in the surrounds will be sent to the rear center with the EX flag on.

Hope this helps...

Andy

Sure it does help, Andy. Thanks so much for the detailed explanation.
Andy:
"(..)That flag is supported in Vegas 5. You'll have to create a new audio setting under AC3 and enable the flag(...)"

So when you encode to AC-3, to enable the flag you mention, I guess you must check Enable Extended Bitstream Information>Dolby Surround EX Mode>Dolby Surround EX Encoded on the guide Ext. Bitstream. Is that the way to enable the flag?
Thanks in advance.

I always thought that 6.1 & up were just marketing by creative to promote their cards were "better" then 5.1 cards.

Guess I was wrong. :)

As this has been answered i wont go into detail, but many people are gettin confused as to what the possibilites really are with DD...

anything more than 6 channels, wont be found on a commercial dvd, however these 5.1 channel ac3 streams can carrry metadata (which is what the EX is all about, ie extended bitstream) which tells the amp HOW TO create the pseudo channels which dont exist within the actual mix..

What nuendo 3 will be doing is allowing you to "virtually" place those pseudo channels, in other words, refining the metadata..

How this metadata will be managed by the player is another question, considering AC3 MD tags are usually preloaded prior to the file launching... what this extended piece means is that this metadata will have to be streamed along with the actual ac3 file a the same time, as it will be fluctuating making changes to the mix..
This is where these specifices 6.1 and 7.1 decoders come into play, as theyre designed to read metadata tags on the fly as opposed to reading the metadata tag in the file header.

big headache... too much thinking.. need coffee