How do I get 5.1 from onboard SP/DIF?

bobboberts

bobboberts

bobboberts

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I've just got a Gigabyte Sniper motherboard, which has onboard sound provided via a Sound Blaster Recon 3D. There is a optical out on the back panel and I have that connected to (via a hub) to my amp. But no matter what I do, I can't get anything other than 2-channel sound. The motherboard manual just says connect either via optical or coaxial (I've tried both) and you'll get 5.1 but I tried some test videos on Youtube and...nothing.

This is, incidentally, exactly the same issue I have with the previous dedicated card I had (a Sound Blaster X-Fi Extreme Audio) - I've never been able to get it to work. I am hopefully missing something really, really stupid here, so please tell me, because this has frustrated me enormously since I originally got the X-Fi on my previous build 6 years ago!

Edit: I should add that I've tried it with the X-Fi too and that doesn't seem to work either. For the Recon3D in the sound options panel it lets me configure speakers, but no sound comes out when I do the test. For the X-Fi it would never seem to let me even see any speakers, let alone test them. I run Windows 8.1, if that makes a difference (used to be on Vista).
 
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It will only run 5.1 with a Dolby or thx 5.1 source other wise it will be stereo, some weird thing about bandwidth/encoding I never understood. My creative dts100 shows when its stereo or surround via led on the front and indeed only goes surround with a blue ray or DVD or a game that supports Dolby etc, YouTube etc runs stereo, am afraid there is nothing u can do! In settings make sure spdif is sending Dolby, thx (whatever the other one is) hope this is helpful
 
Not sure as not got digital speakers.

Edit: Not sure I am right but I am sure it does that also be it another setting with DTS Neo.


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No one has digital speakers because we cannot hear digital, you need a digital to analogue converter (DAC) to convert optical signals.
 
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Well I hadn't noticed the setting you posted there, so thanks for that, however it still only plays out of the front speakers (though that's more than it was doing before). The test signal for the sub doesn't get picked-up by my receiver, either.
 
To pass 5.1 over SPDIF, the audio stream needs to be encoded with Dolby Digital or DTS. Without either, the sound comes out as stereo, as SPDIF doesn't have the bandwidth to support uncompressed multi channel. DVDs have Dolby and/or DTS tracks, so they will be passed on via the SPDIF connect by the software player. Games however do not use DD or DTS, so that's why you are only getting stereo.

Which Sniper board do you have? You'll need either Dolby Digital Live or DTS Connect to encode the audio to 5.1 in real time. The receiver will decode them as DD or DTS, whichever you choose to use. Some Sniper boards have one of these features, but some don't.
 
I've got the G1 Sniper Z87.

Like I say though, I haven't got it to work with my X-FI Extreme Audio card, which surely does do encoding on the fly?

I accept that I won't get DTS or DD for everything, but is it not possible to get the 'Play stereo mix to digital output' option to work through all channels? Currently it plays the rear speaker test sound through the front speakers and ignores the sub completely.
 
I would have thought that the Z87 would have DDL and DTSC, given it has Core3D audio, but there is no mention of either among the specs. The Sniper 2, for eg, has a X-Fi audio processor, and has both DDL and DTSC listed. Looking at the various Sniper boards, it would seem the majority of them do not have DDL or DTSC.

The Xtreme Audio doesn't have DDL or DTSC. Although it's sold as a X-Fi, it's actually an older Audigy card that Creative repackaged.

Even if the receiver is getting stereo, I would have thought that Dolby Pro Logic can applied to upmix it to output from all speakers. I think that's standard on all AV receivers.
 
The speaker package is an old Sony STR-K740P and is about 10 years old. It has Pro-Logic II but is playing the rear channels through the front speakers. Even the sub is playing through the centre channel. It is set to surround, yeah and I've played around with various modes on it.

So are you saying it isn't possible to get stereo upmixed (using Pro-Logic II) with either the onboard sound or the X-Fi card over optical? If that is the case, what card would allow that?
 
Yes, it is possible, and the receiver should be doing that if Pro Logic is selected. That should work from any motherboard or sound card with a optical connection. Stereo is stereo, whether it's sent from a motherboard or an expensive sound card, it will be no different. It's the receiver's job to upmix that stereo to 5.1 using Pro Logic, irrespective of what it is connected to. If that's not working correctly, it could a setting maybe that isn't allowing it to work. Maybe the sample rate is set too high in Windows for it to work correctly, or maybe it's something on the receiver.

Ideally though, getting a sound card would probably be the best, as it will allow the receiver to decode Dolby Digital or DTS as true 5.1 encoded by the sound card. The only question I have is, will that work correctly? Normally yes, it would be; however seeing as the receiver is not upmixing stereo correctly with Pro Logic, it would be best to investigate that first and why that isn't working as it should.
 
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