AVS Forum banner
Status
Not open for further replies.
1 - 20 of 43 Posts

·
Registered
Joined
·
168 Posts
Discussion Starter · #1 ·
Are there any plans for a Dolby Digital sound card that will decode the digital signal on the fly like Nforce does except in 7.1?
 

·
Registered
Joined
·
214 Posts
I recall reading around the time of Nforce launch that to do DD encoding over a PCI bus wasn't possible due to bandwidth issues. I guess with the new PCI Express bus format next year this issue would be removed and some DD encoding cards would appear.
 

·
Banned
Joined
·
7,766 Posts
one would think that bandwidth wise you only have to worry about getting the 5.1 channels to the card, which is something that current cards already do. once the audio channels are to the card, it would be up to the sound proc to encode them, which would not be a bandwidth issue at all, but more of a sound proc capability issue.
 

·
Registered
Joined
·
551 Posts
CMI also has Dolby Laboratories certified software real-time DD encoder using their CMI-9739 from Jan 2003, first news and second news . However, I've not heard anything after that.


This time, in WPC Expo 2003, I guess CMI is announcint something new. Because, Their web page shows CMI9761+ as new DD solution and their flyer is showing DD encode as their new coming feature. It looks like promising. :D
 

·
Registered
Joined
·
6,902 Posts
Wow, looks promising. Can't wait.
 

·
Registered
Joined
·
6,902 Posts
The Maya 7.1 (or Prodigy for that matter) don't say anything about encoding DD, which is what we're looking to do.
 

·
Registered
Joined
·
37 Posts
Sorry, I misread the topic.


So why exactly would one want to encode 7.1 audio in realtime (or 5.1 for that matter)? I come from a DAW (Digital Audio Workstation) background and surround sound mixing is something that requires expensive high end equiment to create in the first place.
 

·
Registered
Joined
·
551 Posts
Just ease of setup. Don't you wanna connect gaming HTPC and AV amp with single digital cable instead of 2, 3 or 4 analogue lines? ;)


BTW, this is not useful for pure HTPC since we can use pass-through for this case.
 

·
Registered
Joined
·
37 Posts
Quote:
Originally posted by kazushi
Just ease of setup. Don't you wanna connect gaming HTPC and AV amp with single digital cable instead of 2, 3 or 4 analogue lines? ;)


BTW, this is not useful for pure HTPC since we can use pass-through for this case.
Well, doesn't that mean the Maya 7.1 encodes Dolby digital then if it has a TOSLINK output?

Enter a new world of home theater entertainment with the MAYA 7.1 surround sound audio card.

MAYA 7.1 provides two high-fidelity analog inputs and eight discrete analog multi-channel outputs for Dolby Digital 5.1, EX, and DTS 5.1, ES for true surround sound and virtual surround sound for 5.1, 6.1 and 7.1 speaker configurations. When watching a DVD movie, MAYA 7.1 can supply a multi-channel surround sound environment with a digital audio connection to a home theater system or from the multiple analog audio outputs and a surround speaker system, resulting in audio reproduction the way the movie was originally intended.
 

·
Registered
Joined
·
551 Posts
No.


I think their advertisement is misleading, but pass-through of DD signal and real-time DD encoding are completely different. If you think MAYA7.1 should support real-time DD encoding, ask audiotrak.net, please.
 

·
Registered
Joined
·
456 Posts
brzilian


From the text you quote, the implication is that on the Maya the digital audio connection is only available "when watching a DVD movie". That would mean that, like evey other audio card, it does SPDIF pass through when the DVD itself has DD or DTS sound on it.


Six reasons people might want a soundcard which can do DD (or DTS?!) encoding on the fly are as follows:


(1) PC games with multi-channel audio


(2) Slowing down the audio by 4% on a PAL DVD of a movie (25 frames per second, which for purists should be slowed down to 24 frames per second) and retaining the DD or DTS sound


(3) Playing DVD-A or a SACD on a PC (assuming the drive can physically read the disk: I'm pretty sure that SACD is physically readable by a DVD drive), using software to decode the DVD-A or SACD multichannel sound and then reencoding it in DD


(4) Cheap method of auditioning home-made (or semi-professional) multichannel soundtracks for DVDs


(5) Using PC as a digital graphic equaliser, e.g. for digital room correction


(6) Rebalancing the channels on DVDs, for example for my tastes on most film DVDs the centre channel is about 3dB too quiet. With appropriate software (in, say, 2 years time) you could set your own custom channel balances on a 'per-DVD' basis, in the same way that using Zoom Player you can currently set (and have the PC remember) aspect ratios, image size and position, and brightness, contrast and gamma levels on a per-DVD basis.


All of the above assumes that your audio set-up consists of a PC connected to a high-end pre/pro or multichannel receiver via an SPDIF connection, which is to my mind the only way to do HTPC audio properly. The reason is that PC multichannel sound cards are simply not audiophile enough on the analogue outputs. (Also in my particular case, my pre/pro despite being otherwise excellent, has no multichannel analogue inputs.)
 

·
Registered
Joined
·
6,902 Posts
Quote:
Originally posted by inti
brzilian


From the text you quote, the implication is that on the Maya the digital audio connection is only available "when watching a DVD movie". That would mean that, like evey other audio card, it does SPDIF pass through when the DVD itself has DD or DTS sound on it.


Six reasons people might want a soundcard which can do DD (or DTS?!) encoding on the fly are as follows:


(1) PC games with multi-channel audio


(2) Slowing down the audio by 4% on a PAL DVD of a movie (25 frames per second, which for purists should be slowed down to 24 frames per second) and retaining the DD or DTS sound


(3) Playing DVD-A or a SACD on a PC (assuming the drive can physically read the disk: I'm pretty sure that SACD is physically readable by a DVD drive), using software to decode the DVD-A or SACD multichannel sound and then reencoding it in DD


(4) Cheap method of auditioning home-made (or semi-professional) multichannel soundtracks for DVDs


(5) Using PC as a digital graphic equaliser, e.g. for digital room correction


(6) Rebalancing the channels on DVDs, for example for my tastes on most film DVDs the centre channel is about 3dB too quiet. With appropriate software (in, say, 2 years time) you could set your own custom channel balances on a 'per-DVD' basis, in the same way that using Zoom Player you can currently set (and have the PC remember) aspect ratios, image size and position, and brightness, contrast and gamma levels on a per-DVD basis.


All of the above assumes that your audio set-up consists of a PC connected to a high-end pre/pro or multichannel receiver via an SPDIF connection, which is to my mind the only way to do HTPC audio properly. The reason is that PC multichannel sound cards are simply not audiophile enough on the analogue outputs. (Also in my particular case, my pre/pro despite being otherwise excellent, has no multichannel analogue inputs.)
Nice reasons, especially #1 and #6. Hopefully someone soon will come out with this, though you'd think Nvidia would've done it by now (just another way to make money for 'em). Heck, I'd pay $200 in a heartbeat for a soundcard that could do it.
 

·
Registered
Joined
·
551 Posts
Hi intl,


I think real-time DD encoding has problems if we want to use our HTPC as an aggressive audio device. DD encoding is very lossy compression. It will be ok for gaming, but I'm in doubt about other usages.


Firewire looks promising, but I'm not sure how it goes. (I don't believe USB 2.0, btw. :))
 

·
Registered
Joined
·
456 Posts
taz, that is kind. I would also pay for a soundcard that could do it. I'm sure the soundcard would be fairly expensive as they would have to pay licence fees to Dolby and DTS.


Actually, in my view reasons (2) and (3) would be commercially the most important. More on reason (2): in Europe (a market approximately twice the size of the USA) we have PAL DVDs, which as you may know have better video (20% more resolution, no 3:2 pulldown problems) but a 4% speedup in playing time and hence a pitch change for audio somewhere between a quarter tone and a semitone which a few people find annoying. A solution which could play PAL disks at 24 fps and retain DD or DTS output could be very successful, commercially. (Equally, a standalone DVD player which could do it would probably wipe the floor with the competition.) Australia and New Zealand are the other major PAL markets, although only 1/20 the size of Europe. (I'm not sure about Latin America or South/South-East Asia - for example, Malaysia has the PAL TV system but I'm not sure whether their DVDs are PAL or NTSC like most R3s.)


More on reason (3): as far as I know, there is no existing software to play DVD-A or SACD on a PC. It is bound to come some day soon (closely followed by MP5.1, no doubt, being a new format for saving multichannel music onto your hard drive). When this technology reaches the PC world, there will be one more reason to have a multichannel sound card. Again, as sound cards analogue outputs are not audiophile, there would be a powerful reason to encode back into a format that can be carried by SPDIF.
 

·
Registered
Joined
·
37 Posts
Sorry for the newbieness.


I'm just trying to get a grasp of what people are looking for as far as audio in a HTPC.


Like I said before, I have a background in professional computer recording using DAW's.


While I think it would be cool to bring that level of control of a surround sound mix like you describe on #4, I think it is something better left for pros who use high end computer audio equipment. There are dedicated pieces of hardware for that exact purpose which are priced in the thousands of dollars. You also need to have somewhat of a sound engineering background as well to be competent at it - its not for everyone.


As far as DVD-A's, don't the Audigy2's from creative possess the capability of playing them back? (I do realize that Audigy's do not have a DD output to an external decoder - I am jsut referring to the fact you can indeed play back a DVD-A on a PC with an Audigy 2 card.
 

·
Registered
Joined
·
6,902 Posts
Quote:
Originally posted by brzilian
Sorry for the newbieness.

As far as DVD-A's, don't the Audigy2's from creative possess the capability of playing them back? (I do realize that Audigy's do not have a DD output to an external decoder - I am jsut referring to the fact you can indeed play back a DVD-A on a PC with an Audigy 2 card.
Yes, the SB Audigy 2's do decode DVD-A, which is one of the major reasons I'm leaning towards that card (not to mention the firewire ports).


I don't think the reason behind there are no DD encoding soundcards is due to licensing fees. Nvidia already pays the fees for their MB to do it, so why not make a stand-alone soundcard to do it? I'm sure there must be another reason.
 

·
Registered
Joined
·
779 Posts
brzilian,


You are a funny guy. The reason most of us use a home theater compuer instead of dedicated equipment is to save $$$ and get equal capabilties. It no longer requires thousands of dollars of hardware / software to create a DTS or DD soundtrack.


Here's a quick list of inexpensive software that will allow you to encode your own DD or DTS soundtrack in full 5.1: Reason 2.0 (it will even do the backround mix!), Pro audio 6, Surecode DVDpro (DTS only), Logic platium (does 7.1 at 192khz)


Here's two ways I use "home grown" DTS and DD often:


1) . I take my family DV video's, and run the 2 track PCM audio into Sonic Foundry's Sound Forge 6.0 application ($99 dollars - 7.0 is out, but you don't need it). It has a whole series of project templates and fade curves that will take a stereo music track and automagically create an ambient 5.1 soundstage out of the four channels. Gives our family DVD's a professional touch that's meaningful. If you want to spend a bit more money, Vegas Video will do all of this for you within it's video editing timeline for $150.


2) ACID 4.0 will output all of your creations in DD / DTS on the fly, with a full 7.1 mixing soundboard. There are thousands of musicians that use ACID to create club mixes, and swap the ACID files
 
1 - 20 of 43 Posts
Status
Not open for further replies.
Top