Possible to set up surround sound from PC?

Bill Turnip · 8 Sep 2021 at 10:21

I currently have a PC set up in my office that I am running cables from to the TV in my front room, the idea being that I can use the front room for playing games when I am feeling like crashing on the sofa for an evening. I have an active HDMI cable (active as the distance it needed to run is around 20m - exact opposite corners of the house!) that I have run from the GPU in my PC to my TV which works perfectly, but it will only seem to pass stereo, as opposed to surround sound through this cable. The TV is connected to a Sonos surround sound system by optical cable.

My questions are:

1. Is surround sound possible with this set up?
2. If so, is it possible using just the HDMI cable?
3. If not, would it work with an optical cable from motherboard (Gaming edge wi-fi) to sonos?
4. If the optical cable wouldn't work, any other potential solutions?

I've had a look at Nvidia's website for passing surround sound over HDMI with no joy, so was wondering if anybody here had any better ideas. It's not a dealbreaker if it is impossible, I'm not a competitive gamer or anything like that but it would be good to use the front room setup to its full potential.

EsaT · 8 Sep 2021 at 15:18

You need to configure that HDMI sound output for 5.1/7.1 in Windows sound settings.

Bill Turnip · 8 Sep 2021 at 15:45

I have already tried to do that, but I run the tests and the surround speakers only act as left or right, and the sub has no output at all. The sonos app also shows that the signal being received is only 2.0.

alex24 · 8 Sep 2021 at 15:54

Have you checked the specs of the active HDMI cable?

Dwarfy · 8 Sep 2021 at 15:55

does the active cable support the audio feed? I only ask because I searched for an active cable and it listed supporting 8 Ch Audio, so made me wonder if some do not support it.

Bill Turnip · 8 Sep 2021 at 16:15

alex24 said:
Have you checked the specs of the active HDMI cable?

It's an active hdmi 2.0, so I think that it would be fine, although I'm happy to be corrected. The hdmi is connected to the TV, which is then connected via optical to the sonos, maybe the conversion to stereo is forced by my TV?

alex24 · 8 Sep 2021 at 17:25

What active cable model and what model TV is it?

It may be that the TV can't pass-through more than stereo to optical, I've seen similar issues before.

Bill Turnip · 8 Sep 2021 at 18:05

The TV is a Sony AG8, and I THINK this is the cable - https://www.kenable.co.uk/en/hdmi-c...s-4k-60hz-2160p-20m-010013-5054338100135.html

As far as I can tell, they would both support pass through, and I can confirm that he hdmi from the pc is plugged into the e-arc input on the TV.

I'll try and bring the pc downstairs later and connect from motherboard direct to sonos with optical to ensure that it does work. The ideal solution would be to use the already existing hdmi, just trying to check every aspect first.

Rroff · 8 Sep 2021 at 18:10

alex24 said:
What active cable model and what model TV is it?

It may be that the TV can't pass-through more than stereo to optical, I've seen similar issues before.

I seem to remember this being the case - without a specialised setup optical is usually 2 channel.

EDIT: Yeah on Googling most TVs only pass through stereo on optical - you need a specialised setup to have multi-channel over optical.

Bill Turnip · 8 Sep 2021 at 18:22

Right, in this case it seems like the TV pass through is the stumbling block as the sky box is connected directly via optical and works fine. I've read that long optical cables are not generally a good idea due to signal degradation, but I suppose the only way I would know would be to buy one and try it?

By the way, thank you all for your tips so far, its appreciated.

james.miller · 8 Sep 2021 at 18:24

Buy a hdmi audio extractor. They arent expensive

Bill Turnip · 8 Sep 2021 at 18:38

james.miller said:
Buy a hdmi audio extractor. They arent expensive

I didn't even know that they were a thing, they seem like they may solve the problem! Certainly seems like a better idea than mine, thank you. I'll have to have a look to find one that does 4k 60hz, but as long as I can confirm the gpu outputs 5.1, this could be perfect.

Dwarfy · 8 Sep 2021 at 20:02

Another alternative would be a hdmi splitter, I used to use one before I got Sky-Q to split the sky and then I ran an HDMI cable to the TV in the bedroom directly above.

Bill Turnip · 8 Sep 2021 at 20:24

Dwarfy said:
Another alternative would be a hdmi splitter, I used to use one before I got Sky-Q to split the sky and then I ran an HDMI cable to the TV in the bedroom directly above.

Thanks, but I don't think the HDMI splitter would work, as the only input on the Playbase is an optical input only. I already have an optical splitter with a spare connection, I was simply unaware that the HDMI audio extractor existed.

As I understand it, it would be HDMI from my GPU to the HDMI audio extractor. From there, I would send an HDMI signal to the TV for picture, and an optical signal from the audio splitter to the Playbase. Does this make sense?

Bill Turnip · 8 Sep 2021 at 21:40

Looks like the HDMI audio extractor may not work - Whilst going lower on the google search results, I came across an old thread from this very forum that shows the problem may be windows not encoding as DD 5.1, which means that even if I had a direct connection, it wouldn't work without a dedicated soundcard.

Grim5 said:
That won't work on Sonos sorry.

That 5.1 Option you see in Windows is Uncompressed. As such the Sonos product will play it as Stereo.

Sonos only accepts an Pre Encoded Dolby Digital signal for 5.1 surround sound. And Windows doesn't encode sound output into Dolby formats, because they would have to pay a very expensive license to Dolby to have this feature.

This works for you because your receiver is capable of playing uncompressed multi-channel audio, Sonos products cannot do this.

@OP: If this is all starting to sound very complicated that's because it is. You may even wish to get rid of the Sonos product and buy another branded soundbard - one that can play multichannel uncompressed audio.

If I understand this all correctly, it seems like being able to do this with just the HDMI cable (with whichever splitters I would require) I currently have isn't a possibility with the sound system I have. I'm not changing the sound system on the front room as it works perfectly for everything else, so if I want to do this it seems like I will need a dedicated sound card (to do the DD 5.1 encoding), which means I would then need to follow up with an additional audio cable over a long distance (which has its own issues). Darn.

Any other ideas at all?

Bill Turnip · 9 Sep 2021 at 17:43

I've looked into this a little further and also now brought my PC downstairs to connect to the playbase direct via optical cable. When I run the Windows test, or play from the Netflix app, Dolby Digital works. When I try to run a game (In this case, Witcher 3), or even any other sound it doesn't, the computer only outputs stereo. My understanding is that the Windows test and Netflix are pre-encoded as Dolby Digital, but the game is not and requires encoding on the fly. To do this, I believe I would need to have a soundcard which does this as the GPU only passes audio through and doe not encode it.

I think that the PC would require a soundcard to encode the sound as it is produced, prior to forwarding to the receiver. I have looked at the Soundblaster Z SE (I haven't used a Soundblaster product since I was about 8!) which seems like it would fit the bill, but is a bit pricey for what I am after. Any cheaper recommendations on soundcard that can do this at all?

Radox-0 · 10 Sep 2021 at 00:12

I think you having Sonos makes it harder then some other methods. That said some people picked up a sound blaster Omani with some success and Sonos to get surround sound in this thread https://forums.overclockers.co.uk/threads/5-1-from-pc-to-tv-sonos-system.18869394/page-2

Bill Turnip · 10 Sep 2021 at 00:18

I have been playing around with the onboard sound drivers all day, and have now got it working with 5.1 surround with everything whilst the pc is downstairs. I've ordered a 20m optical cable to run between the two when my PC is back in the office but am aware that this may not be as reliable as intended.

Figured the only way to know for sure is to try it, I can always test it before returning the PC to its intended location. If it doesn't work, I return the cable, if it does work I've saved the price of a sound card!

alex24 · 10 Sep 2021 at 09:58

If a sound card would solve it, I would be tempted to pick one up cheap/second hand anyway as you'll get better quality sound than onboard. Sorry to throw spanner in the works, just didn't think that onboard sound would be the root of your issue.

Bill Turnip · 10 Sep 2021 at 11:07

Nothing to be sorry about, a sound card would possibly be a more reliable option with regards to sending the correct signal, but it wouldn't get around the fact that I would need a long optical cable. I've managed to get the system working as I would now like it, subject to the cable length.

If the cable doesn't work, I will need to see if there is a good alternative, possibly optical cable from pc into converter, a different, more reliable cable covering the bulk of the distance before converting back to optical at the other end. I just don't (yet) want to spend too much doing this, as it is only a nice to have...although that may change!