Dolby Digital Live output

[Gigantor]

Just a little tip I thought I'd share, because it took me forever to find what I needed on other forums.

I wanted to be able to output dolby digital 5.1 from my HTPC, but I wanted to connect it up to a proper HT speaker system, as most PC based speakers don't really cut it. Unfortunately, all the good digital receivers I looked at did not have an SPDIF input - but only an optical input. Also, I found that a number of PC applications, particularly games with 5.1 (i.e. Doom 3), did not put out proper 5.1 sound when connected to an external receiver. They seemed to revert to stereo sound.

I finally discovered the HDA Digital X-Mystique 7.1 card, which is available quite cheaply. This little beauty has an optical as well as SPDIF output, and uses something called Dolby Digital Live to encode all 5.1 sound so that it works properly with external receivers. The only downside is that it doesn't have hardware EAX, so games take a performance hit when using EAX, but for me it's well worth it for the surround effect. I had to turn off Doom after a while because it started scaring the **** out of me!

Highly recommended.

Big G.

[reboot]

That card has been on my wishlist for quite awhile.
My wife loves her games, and PC speakers, no matter how good, just don't have the effect of a home theatre, with the game played on the TV.
A friend has one, and you're right, Doom3 get's extremely creepy with the right audio effects!
I also have been attempting DD5.1 audio as an alternate track on my DVD burns, so it will be nice to finally be able to use it via gbpvr's player

[betlit]

*lol* for me the stereo speakers of my computer were enough to constantly thinking 'i would rather save and close doom 3 than open _another_ door'

but here i am. i survived *g* sent all the fscking creatures back to hell (and betruger with them).

btw: betrüger is german and means "cheater" *gg*

[nitrogen_widget]

Hello All,
New here & awaiting my PVR150 from newegg.
I was wondering about 5.1 out from the PC.
I have a number of SB LIVE! cards with digital out.
I was planing on purchasing a receiver with a 5.1 digital input (my current receiver is an old Pioneer 4 channel surround without individual inputs) & hooking it up that way but it sounds like it isn't that simple?

[capone]

If your sound card has a optical or coax s/pdif connector, and you have/are getting a receiver w/ an in for it, then you have the set up I have.

The sound card doesn't even matter that point, as it is just going to pass the audio directly to the reciever. The only settings that will matter are those for the decoder and and post-proessing apps you use to handle audio.

[KingArgyle]

If you have FFDSHow installed (at least the audio filters), you can do realtime conversion to DD 5.1 for any show you recorded. Check this thread for how to do it:

http://forums.nextpvr.com/showthread.php...fdshow+ac3

[Gigantor]

I don't mean to argue, as I do not by any means consider myself an expert, but in my experience with the digital out on my old sound card, 5.1 sound did not work properly with external receivers.

I tried an Audigy 2 Pro card, which includes an optical out and has an option in the driver to output an unprocessed digital signal. However, this did not produce a 5.1 experience in all cases. As I understand it, most applications, including games, do not use a true dolby digital signal, so an external receiver cannot process it correctly. Soundcards like the 'Mystique' (see above), use a feature called dolby digital live (see this link: http://www.dolby.com/consumer/technology...live.html). This converts all audio output from the PC to a dolby digital bitstream, which external receivers can decode properly. Most soundcards, including the entire Soundblaster range, do not perform this step, and you do not get true 5.1 from any application that does not create dolby digital output.

Other soundcards, and some high end motherboards also use dolby digital live, but many of the most popular do not.

[capone]

I have a Chaintech I got just for the optical out, and plugged it into my Sony HT receiver. I set up ffdshow (thx to King back when he posted) to pass the right number of channels as the source file (so 2.1 for TV and 5.1 when avail in avi, dvds, etc). I also have it resampling all audio to 48k.

The result is the display on the Sony shows exactly what the audio source is. It shows 2.1 or 5.1, and has the right speakers active (only...so it doesn't use all 5.1 for 2.1). I can also attest that it is legit surround, w/ sounds moving aroudn the speakers as it is designed to (eg, hearing a cannon on back left of screen in movie go from the back speaker, though the front, and "land" on the other side of the room).

It did take that extra love from ffdshow to pass it "right", but the soundcard was about $20, and there's nothing I can configure (even volume) that has any effect, since it doesn't do anything to it.

[nitrogen_widget]

Ok.
I knew that all the sound card was doing was passing along the digital signal.
There is a digital out only setting in the software that needs setting.

I had a flaw in my thinking because I assumed it would put everything out as digital 5.1. For some reason I was missing the fact it didn't generate a 5.1 signal it pulled it off of something.
I was mostly thinking of DVD's & premium movies.
I'd hate to be forced to watching them in plain stereo as I don't think a sound card can output the dolby surround to the receiver on just two cables like my set-top DVD player, VCR, & sattelite dish.
Unless it can.
But then that would depend on the PVR-150 card correct or is it just embedded in the signal?

This really confuses me.

[capone]

I'm a little confused what you're exactly asking, too.

What I can say is that the audio from the 150 is 2.1. This is because I have just analog catv, so it's all the audio I get. If I was getting 5.1 from digital, I presume I get 5.1 from the 150 to pass to the sound card (and along from there). That would still only be the case if what I was watching had 5.1 audio, which most broadcast tv does not anyway (some news channels don't even bother w/ doing stereo at all).

But, when I watch video w/ it encoded as 5.1, I get 5.1. If the video was only encoded w/ 2ch/2.1, that's all I get (eg, mp3 audio track, but I read next gen of mp3 encoders will support multichannel). I don't have the reciever/ffdshow making 5.1 when it doesn't exist.