Spdif passthrough for games

[alto123]

Hello,
I have a home theater system which I connect from my computer through SPDIF optical cable. I have the following mother board and inbuilt sound card - Gigabyte 880GM - USB3, sound card - Realtek 892ALC which has Dolby Digital Live. I have managed to passthrough audio using AC3 filter when playing through Media player classic every processing is done by the AVR. But I want that from games too, the passthrough is not happening for games, for which I want the sound to be processed by AVR not sound card. Be it 5.1 or 2.1 I want complete passthrough. Is it possible to do?

 

[alto123]

Ok just got done looking up your audio CODEC and there could be a few solutions.

First what drivers do you have loaded, were they off the motherboard's CD or did you go to Realtek and get it from them.

The one provided with motherboard driver.

Also what is your default setting under windows sound playback?

Control Panel -> Sound -> Playback Tab -> Digital Output -> Properties -> Advanced

Dolby digital Live(5.1 surround) is selected

Also are you using Windows 7 or Windows Vista? This is an issue because as of Vista Microsoft is forcing everyone to use the universal windows audio control rather then letting programs directly talk to hardware. This could be an issue if your game tries to speak EAX and doesn't know to translate it through the audio center first.

I am using Windows 7 64bit
The receiver I am using is Harman Kardon 134.

 

[palladin9479]

^^ Paladin, his chipset has DDL support, so 5.1 via SPDIF shouldn't be a problem. DDL does NOTHING but convert a 5.1 PCM stream to Dolby format, so as long as the game can output standard 5.1, he should have no troubled getting 5.1 audio via SPDIF.

Though you MAY have stumbled onto the root problem: What games are you trying to send 5.1 from? Under the new audio architecture [starting with Vista], Directsound is a 2.0 software API. If the game is old enough, you will not be able to output 5.1 using any connection type. [I believe Realtek has a seperate "3d soundback" driver that fixes this though...]. This shouldn't be affecting any modern games though, but it could be part of the problem...

I realized this after I had posted. I was referencing the "DDL" as being "DDL passthrough" where the audio chip is just relaying the DDL / DTS audio data instead of encoding it. Nicer cards / chipsets do have the ability to encode from 5.1 PCM DDL / DTS. I use HDMI for everything so I haven't had to mess with this for ages.

 

[palladin9479]

The one provided with motherboard driver.


Dolby digital Live(5.1 surround) is selected



I am using Windows 7 64bit
The receiver I am using is Harman Kardon 134.

Ok that answers lots of questions. Your audio chip is capable of encoding 5.1 PCM into DDL and will do so if it's handed the proper data.

Which means the problem almost certainly lies within the software producing the sound data. Look into that "3D back" software I mentioned above, it could be that your game can't find any EAX or other hardware based 3D sound chip and is defaulting to DirectX 3D sound emulation. That just takes the sound data and creates a stereo two channel sound stream that tries to sound like 5.1.

 

[alto123]

Though you MAY have stumbled onto the root problem: What games are you trying to send 5.1 from? Under the new audio architecture [starting with Vista], Directsound is a 2.0 software API. If the game is old enough, you will not be able to output 5.1 using any connection type. [I believe Realtek has a seperate "3d soundback" driver that fixes this though...]. This shouldn't be affecting any modern games though, but it could be part of the problem...

5.1 or 2.1, want the sound only to be processed by the AVR. I am running black ops that has the option of choosing digital(optical) or speakers, but did not help either.

 

[erly_Cuylers]

go to Control Panel -> Sound -> Playback Tab and tell us which one has the green check on it?

I'm still covinced this is a configuration problem, just some simple check or click, here or there. it's just been so long since ive used Windows I forgot how to run it through my head.

cheers

 

[alto123]

go to Control Panel -> Sound -> Playback Tab and tell us which one has the green check on it?

Under playback tab - Speakers, Realtek Digital Output, Realtek Digital Output(Optical) is listed and Realtek Digital Output(Optical) is with a green tick mark.


One thing I want to ask, if I use HDMI for games what will happen? Will the sound directly come out of the speakers without being processed or nothing will come out?

 

[alto123]

Hello gamerk316, erly_Cuylers, palladin9479
please respond to my issue posted above.

 

[palladin9479]

Depends on if the HDMI on your GPU is pass-through or a real audio device.

 

[alto123]

Depends on if the HDMI on your GPU is pass-through or a real audio device.

GPU I have - ATI Radeon 5770, it has HDMI (manual says it can handle 7.1) . So is it possible to bitstream/passthrough to AVR?

 

[gamerk316]

Under playback tab - Speakers, Realtek Digital Output, Realtek Digital Output(Optical) is listed and Realtek Digital Output(Optical) is with a green tick mark.

Thats the problem. Select "speakers", and then configure the driver software to use SPDIF output. Do not use the optical port as the default output.

For whatever reason, when "Speakers" are not selected as the default output device, the SPDIF port is limited to two channels. I forget why this occurs though...Hence why you have the set Speakers as the default, then configure the software to use the SPDIF output port.

 

[alto123]

Thats the problem. Select "speakers", and then configure the driver software to use SPDIF output. Do not use the optical port as the default output.

For whatever reason, when "Speakers" are not selected as the default output device, the SPDIF port is limited to two channels. I forget why this occurs though...Hence why you have the set Speakers as the default, then configure the software to use the SPDIF output port.

Could u pls elaborate how to do it?

 

[gamerk316]

^^ For a realtek? No idea offhand, though theres probably an option for spdif output somewhere in their driver control panel to use the SPDIF output as the default.

Its the same deal with my ASUS cards; if I select the SPDIF output from the Windows control panel, even if I enable DDL from the ASUS drivers, I only get 2.0 as output. If I select Speakers from the Windows control panel and select the use the SPDIF output from the ASUS drivers, then I get 5.1 via DDL.

 

[erly_Cuylers]

in reading through this thread I've noticed I started repeating myself. this is because of my limited knowledge of the way these things work plus, maybe I was being a little bit lazy. so I am sorry for the lack or repeating of replies here.

the thing is, I think all three of us is trying to figure how to get it to work, just to see if it works. to get you setup with the lesser of two evils and are perhaps ignoring your initial request of setting it up where processing is only done by the AVR. we know what you want but it is not necessarily possible. if you try the configurations we suggest and noting happens, it may be flat out that its not possible with games.

I have a couple of last suggestions. try this as far as how to setup your speakers and choose 5.1 as default.

try an output other than Dolby Digital Live, just try different configurations till you find the one that works. as far as processing being done exclusively by the AVR I don't think it's possible. at least in your case you may have to settle for less.

don't take it from me though, I'm no expert, just a fellow squid who has been to hell and back with this stuff. so I know it's frustrating. however I am unable to find a solution for you.

good luck, erly

 

[alto123]

Ok, let me check the settings thoroughly....
however, 1 thing I do want to know that is ATI Raedon 5770 HDMI is capable of bitstreaming/pass-through, and processing to done totally by the AVR?
Is there any settings to do for it in Windows??

 

[palladin9479]

Ok, let me check the settings thoroughly....
however, 1 thing I do want to know that is ATI Raedon 5770 HDMI is capable of bitstreaming/pass-through, and processing to done totally by the AVR?
Is there any settings to do for it in Windows??

Short answer, yes.

All the ATI card with HDMI have actual 7.1 CODEC's on them. There is no analog output but it will output 7.1 via the HDMI connector. No need for pass-through. Inside windows sound config set the Ati card's digital output as the default sound device. You may have to download the audio drivers from AMD's webpage as few OEM's include them.

 

[alto123]

Short answer, yes.

All the ATI card with HDMI have actual 7.1 CODEC's on them. There is no analog output but it will output 7.1 via the HDMI connector. No need for pass-through. Inside windows sound config set the Ati card's digital output as the default sound device. You may have to download the audio drivers from AMD's webpage as few OEM's include them.

therefore sound processing will be done by the AVR only, isn't it?....

 

[palladin9479]

therefore sound processing will be done by the AVR only, isn't it?....

The sound should be passed over the HDMI connection to the receiver and from there processed into whatever sound environment you have.