GA-X38-DS4 Audio problem on optical s/pdif

[jay_l_a]

Hi,
I have a problem with the audio on my GA-X38-DS4.
OS: XP SP2
I connect to my decoder/amp using the optical s/pdif connector on the motherboard.
I have the latest drivers installed, including the microsoft UAA HD audio driver.
The Azalia codec is enable in BIOS
From control panel/sounds/advanced, I have selected 5.1 speaker configuration.

Now.. the problem...
Using the realtek audio manager I can click on image of the individual speakers to test them.
Only front left and front right respond.
If I play a game with 5.1 support, I only hear front left and front right
BUT
dialog etc is quiet.
This suggests the FL and FR speakers are only reproducing their correct 5.1 output, but center, surround left and right, and LFE are not being reproduced.
ie, it is not simply reverting to stereo. It's as if the speakers mentioned have been disconnected.
I play a surround source from my older PC using digital or optical s/pdif and all speakers work correctly.
Anyone any ideas?
Thanks in advacnce,
Jay

 

[g-paw]

Have you checked the settings of the decoder/amp? There are set ups where the signal has to be decoded by the decoder/amp and you may have to change the 5.1 speaker configuration. Check all the audio set up sections of the manual as well as the Realtek website

 

[jay_l_a]

Thanks for the reply. It's not the amp, as I say the optical s/pdif out on my other PC works fine.
I have noticed some other things.
1. If I use the analog out, I can get the surround sound. My amp does not have full 5.1 analog inputs, so this was tested by plugging the rear out of the pc into the front left/right of the amp. So this is not a solution, merely a test.
2. If I play a DVD from power DVD and set the audio to 'SPDIF' I can get a DVD to play in 5.1

So far, the indication is that this motherboard cannot GENERATE a 5.1 signal and place it on the optical out. It can 'pass through' from a DVD, but if a game has a 5.1 audio option I am still only getting 2 channels.

Any other ideas how I could fix this?
Thanks,
Jay

 

[g-paw]

No other suggestions but it really sounds like an encoding/decoding issue of some kind. On the games do are they actually 5.1 or are do they use software to simulate 5.1?

 

[Bikie]

Hi there, I have the exact same problem, running with a GA-P35-DS3L. I get proper 5.1 through from my TV tuner card, but as far as I can tell it is the only thing. When I also go to the Realtek audio manager the sound only comes from the front left and right speakers.
I am doing various setups and tests to see if I can find the solution, but please let me know if you guy's can think of anything or have a breakthrough.
cheers Bikie

 

[jay_l_a]

On the games do are they actually 5.1 or are do they use software to simulate 5.1?

I'm not sure of the difference. Both COD4 and HalfLife2 have a '5.1 speakers' option in their audio setup.

On my other PC (with optical s/pdif out) the halflife2 5.1 sound works perfectly.

 

[g-paw]

Something can be actually recorded in 5.1, 7.1, whatever or recorded in stereo, which is then "broken' into more channels either electronically or with software. E.g., with my old Creative ZS card if I wanted surround sound, I had to send it as a stereo signal to my receiver and have the receiver decode it even though the card itself had a 5.1 set up for computer speakers

 

[jay_l_a]

I see what you mean. HalfLife 2 generates the distinct channels (5.1).

It is not a matrix signal such as dolby pro logic.

My latest response from gigabyte is

The board can output 5.1 just the application being used for it will need to be written to support optical 5.1

Most applications are written for analog 5.1 support not digital which provides an completely different signal as compared to analog.

....which seems like complete b*llox to me. The WHOLE POINT OF S/PDIF is to carry a multi channel digital signal.
Now gigabyte seem to be saying 'sorry it doesn't do that'

The sound card on my older PC outputs 5.1 channels perfectly on optical s/pdif.

I'm annoyed. When I was spec'ing mobo's I wanted optical sound out so I didn't have to mess around with soundcards. Because of this I probably spent 100 bucks more than I needed to, on something that is now completely redundant and worthless.
Good work Gigabyte.

 

[g-paw]

I may be reading the Gigabyte response wrong but it sounds like it's the application not the sound card itself that has to be written in digital 5.1 and the onboard card is not capable converting analogue to digital prior to outputting it.

 

[jay_l_a]

g-paw, You could be right.
As I noted earlier, PowerDVD will deliver discrete 5.1 over optical s/pdif.

IMO it's a pretty bad implementation if the codec cannot place the same 5.1 signal on both analog and digital outputs.

Feel free to head over to the 'other components' forum (I missed the dedicated sound card one) and help me choose a new soundcard.
Thanks,
J

 

[jay_l_a]

OK, I have an answer of sorts.

Analog signals can be generated by software.

Digital signals need hardware. The GA-X38-DS4 does not possess any such hardware. I can't help but feel the inclusion of s/pdif output on this board is something of a gimmick. It lead me to believe that the 8 channels the motherboard boasts could be delivered over the optical out.
I will learn to research these things more fully.

it would seem that in order to get full 5.1 one needs a DD live equipped soundcard, probably one that sports a c-media codec (either CMI8770 or CMI8788).
J

 

[g-paw]

OK, I have an answer of sorts.

Analog signals can be generated by software.

Digital signals need hardware. The GA-X38-DS4 does not possess any such hardware. I can't help but feel the inclusion of s/pdif output on this board is something of a gimmick. It lead me to believe that the 8 channels the motherboard boasts could be delivered over the optical out.
I will learn to research these things more fully.

it would seem that in order to get full 5.1 one needs a DD live equipped soundcard, probably one that sports a c-media codec (either CMI8770 or CMI8788).
J

The two cards I would suggest are the bluegear or HT Omega. I have the Omega and it's a noticeable improvement over the onboard and am running it through a receiver. I'm running it in stereo because I'm primarily listening to music, which I prerfer in stereo but they meet your criteria. Also there is a link to a review. On the upside we learned something and looks like you got the problem solved Of course the lesson is costing you more than me so I'll sacrifice a couple Bass to the computer gods for you

http://www.newegg.com/product/product.asp?item=N82E16829127002
http://www.newegg.com/product/product.asp?item=N82E16829271002
http://www.elitebastards.com/cms/index.php?option=com_content&task=view&id=318&Itemid=27

 

[jay_l_a]

Thanks for the links.
I had the HT Omega Striker in my scopes.
I'm not sure if the Claro will deliver twice the performance for me (it's twice the price)

The two cards use different codecs. Does anyone know what changed between CMI8770 and CMI8788 (the Striker and the Claro respectively)?

Thanks,
J

 

[g-paw]

I believe the above review gets into the difference and in the review itself there are links to reviews of the bluegear, which use the CMI8788 chip set. As I remember there were significant improvements over the old chip set especially in digital used in movies. I got the Claro+ plus because it could better handle analogue audio and my receiver doesn't have an optical connection but again looking at the differences will help you decide what's best for you but don't discount the bluegear just because it's less expensive and likely a mfg you haven't heard much about. Definitely not a WalMart special company

 

[jay_l_a]

Hmm, I read the review right through. I must go back and check, I must have missed the section where they are talking about the codecs.

Somewhere in my foggy memory I recall hearing negative things about blue gears support. I dealt with that with Auzentech (still one unresolved problem 14 months later).

I've heard (or read) better things of HT Omega support.

 

[g-paw]

Really don't about bluegeats support and had to contact HT Omega about something or another and remember got a pretty quick response. It wasn't anything major. It's been a while since I read that but if I remember correctly the card doesn't use codecs, it does the conversion, etc electronically. I may be wrong but I think codecs are used for encoding audio and video and the playback software has to be able to read that codec. So by the time it gets to the hardware the codecs have been dealt with.