New HTPC GPU, no stereo upmixing for 5.1 receiver

Cantisque

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Hi all,

Not sure where to post this really, but allow me to explain the situation.

I have a PC connected to a Sony AV receiver.

The AMD HD 6670 that was previously in it gave up the ghost in that the HDMI jack appears to be busted (the DisplayPort jack works fine on my other monitor). I replaced it with an Nvidia GTX 660.

Works great, except the audio. I have a 5.1 setup, on my old GPU I could tick the "speaker fill" box in the Windows 7 sound settings which would upmix stereo sources to fill all the sound channels. Unfortunately, this box is no longer present.

This wouldn't be so bad if it also didn't totally ignore my subwoofer as well. Windows knows it's there, you can test it and it will make the thudding noise if you click it in the sound config, but any stereo source from any media player will just ignore it completely and simply stick to the front left/right speakers.

The only way around it is to set the AV receiver itself to stereo mode, this allows the bass to come back.

I've tried searching for workarounds to the missing "speaker fill" box but I can't see anything that I can understand or is related directly to my issue. Ideally I would like some sort of software that upmixes everything on the fly but I don't know if that's possible or will cause unwanted latency.

Again, the speakers all respond correctly in the Windows sound menu when you test them, so the basic configuration is set up correctly and when a 5.1 source is presented, this works fine.

Any advice would be much appreciated!

Edit: I am a noob when it comes to this sort of thing, don't be afraid to point out any obvious suggestions, as there's a good chance I may have missed it!
 
Have the AV receiver create pseudo surround when receiving stereo content rather than using your PC to do so. Engage a mode such as Pro Logic or DTS NEO and the receiver will create pseudo 5.1 from stereo audio sources.
 
The problem is that it sees the PC as a surround source all the time, so using Pro Logic or its own multi-channel stereo sound field setting has no effect. It seems to be outputting multichannel LPCM at all times, just all channels that aren't in use are silent, if that makes sense!
 
The problem is that it sees the PC as a surround source all the time, so using Pro Logic or its own multi-channel stereo sound field setting has no effect. It seems to be outputting multichannel LPCM at all times, just all channels that aren't in use are silent, if that makes sense!

Absolutely does. Spot on. Its more the PC side.

The receiver sees as many channels as what you've set the HDMI output to. Its your PC that decides what to send through those channels.

You have 2 options. The AVR can't upmix because its already seeing 5/7.1. you can try to find some sort of upmixing software, but that's hard to come by and I think not a mature solution yet.

Simpler way is to set the speaker configuration for the AMD soundcard to be2 channel only. that way, your AVR sees only 2 channels, and will upmix it accordingly!

Bit of a pain I know, but believe me, a lot less pain than trying to get your PC to do the upmixing. also too much software manipulation can mess codecs/players up. Best to keep things as simple as possible on PC side so that it bitstreams unadulterated, and let the AVR do the rest.
 
That's a shame. Although multi-channel stereo works fine when I change Windows to stereo as well, I am still unable to get anything except FL/FR from ProLogicII, which I was under the impression was supposed to upmix stereo sources. Do these sources need to be a specific format? The PC sends 24bit 192khz LPCM audio. I can't see any way to change this. Not sure if I need to configure the AV in a certain way to make it work.
 
Nope. LPCM is raw digital like wav is. Any DAC can decode that. Or to be precise, that's the digital bit to be converted to analog.

You should be able to configure PL2 accordingly. Although these days it PL2x Movie or Music
 
I have 2 sound field modes, one PLII MS and the other PLII MV which are for music and movies respectively.

According to the manual, there should be an indicator on the AV display when PLII or any of its variants are being utilised, but this simply doesn't happen. I can see where it should appear, but nothing does, it just ignores the audio completely and outputs FL/FR.

This is when the Windows speaker settings are set to stereo. Any ideas what I am doing wrong?

If it helps, I think my receiver is a Sony DH520(?)
 
OK I think I sorta got it working! (and it's STR-DH810)

Setting Windows to stereo and turning the sample rate (?) down to 48khz allows PLII to work and it does so just fine. Also, setting DTS to SPDIF HDMI passthrough in my media player allows 5.1 DTS to work correctly even while Windows is set to stereo, I guess it just sends the raw audio data to the receiver regardless of what Windows does.

Thanks for pointing me in the right direction about using the receiver to upmix rather than software, would likely be in a terrible mess right now otherwise :).
 
Year 2016, Windows 10, Nvidia GTX HDMI, SONY STR-DN1030, all 7.2 speakers installed. Here are my findings:

If you insist on 2-channel stereo music copy upmix to 5.1/7.1, set your Windows speaker config to 5.1 or 7.1 and then:
- if you only play from web sources, you can use the Microsoft Edge browser which upmixes automatically (besides supporting Dolby sources correctly)
- use Voicemeeter Banana [donationware] to create a new default Windows sound device (configure the speakers to surround) and apply the Voicemeeter's "Stereo Repeat" mode to it (or use a VST plugin like Halo [commercial] for a more sophisticated upmix algorithm).

However.... I have only tried the default upmix done by Microsoft Edge, and I realized that I don't like it -- center speaker too prominent, center of the soundstage moving weirdly when head is moved, and basically being surrounded by monitor speakers just inundates and tires you with sound after a while. I guess this kind of channel duplication should be left for train stations and the like.

I realized I much prefer what my receiver does with the stereo signal in the HD-D.C.S. mode in the Studio setting. However for this, I actually have to feed it with 2-channel stereo music, and thus I cannot have the Windows speaker setup set to Surround. (The HD-D.C.S. can work with that, but the result is worse.)

And so, the only true surround source on my PC being AC3/DTS movies, and after battling with VLC for a while, I have solved this by installing KODI (and allowing the Windows sound device work in exclusive mode), which overrides the Windows speaker/mode settings altogether when watching movies, and outputs true surround sound pass-through (which I think cannot be matched by anything that had to pass compressed through 2 channels, Dolby or not).

UPDATE: Actually, while KODI does multi-channel, it doesn't do pass-through (stable version as of yet; I think it is in the works). The MPC-HC player from K-Lite Codec Pack does pass-through (e.g. your receiver displays "DTS 5.1" etc.), plus it can do the video decoding completely on the GPU, which is funny because the CPU stays at ~0%. I would say the K-Lite is definitely harder to configure than Kodi but if you want a click-and-play pass-through experience, then that's the way to do it.

Hope this helps.

(In my search I have also noticed an emerging 3D surround standard Auro-3D (currently e.g. a pricey Denon AVR-4200W + paid upgrade) which claims to do intelligent stereo upmix out of the box.)
 
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I didn't read all the posts but using Kodi will stop all the windows audio nonsense. It's what I use if I have a 2 channel show that I want to upmix to 11.1. KODI doesn't rely on micosatans windows protocols so it will let you play your music and movies in 2 or multi channel.
 
(updated my post above)
Actually, while KODI does multi-channel, it doesn't do pass-through (stable version as of yet; I think it is in the works). The MPC-HC player from K-Lite Codec Pack does pass-through (e.g. your receiver displays "DTS 5.1" etc.), plus it can do the video decoding completely on the GPU, which is funny because the CPU stays at ~0%. I would say the K-Lite is definitely harder to configure than Kodi, but if you want a click-and-play pass-through experience, then that's the way to do it.
 
(updated my post above)
Actually, while KODI does multi-channel, it doesn't do pass-through (stable version as of yet; I think it is in the works). The MPC-HC player from K-Lite Codec Pack does pass-through (e.g. your receiver displays "DTS 5.1" etc.), plus it can do the video decoding completely on the GPU, which is funny because the CPU stays at ~0%. I would say the K-Lite is definitely harder to configure than Kodi, but if you want a click-and-play pass-through experience, then that's the way to do it.

I'm not sure I follow when you say passthru? KODI does passthru the audio unmolested, where windows will default it to whatever you set it at, (5.1 or 7.1) and with a stereo track it will only come out of the L+R channels.

With KODI it'll take a 2 channel and upmix it to however many channels you have selected in it's menu by bitstreaming it.

Maybe we're talking at cross porpoises?
 
I use a windows 10 machine as my htpc and to get the upmix audio u have to setup your speakers as being 2.1 in the audio properties.
Now I use kodi which does audio pass through so if I'm watching a 7.1 DTS hd film say it will output the audio as required, no audio processing done by PC the avr does it all, detects the correct audio format and outputs it to the relevant speakers.
 
There is a difference (perhaps not an audible difference) between a true pass-through and a multi-channel LPCM -- if "Enable pass-through" is missing in KODI's audio preferences (like on my PC), then KODI converts the source DTS or DD into multi channel LPCM - so the receiver displays "LPCM" instead of e.g. "DTS". Both ways have their own advantages, pass-through is pure, LPCM can have further procesing applied by KODI, if requested. AFAIK.
 
There is a difference (perhaps not an audible difference) between a true pass-through and a multi-channel LPCM -- if "Enable pass-through" is missing in KODI's audio preferences (like on my PC), then KODI converts the source DTS or DD into multi channel LPCM - so the receiver displays "LPCM" instead of e.g. "DTS". Both ways have their own advantages, pass-through is pure, LPCM can have further procesing applied by KODI, if requested. AFAIK.
The pass through option will be missing if you are running osx machine or you haven't got the drivers installed correctly eg. Ur graphics card. I had this issue until I resolved it by loading bootcamp windows 10 and installing the right graphic card drivers. I know what ur thinking graphic card drivers ?? But yes if you have a HDMI port, then its able to handle hd audio and it needs to be able to pass through that hd audio correctly via its HDMI port to your receiver.
 
There is a difference (perhaps not an audible difference) between a true pass-through and a multi-channel LPCM -- if "Enable pass-through" is missing in KODI's audio preferences (like on my PC), then KODI converts the source DTS or DD into multi channel LPCM - so the receiver displays "LPCM" instead of e.g. "DTS". Both ways have their own advantages, pass-through is pure, LPCM can have further procesing applied by KODI, if requested. AFAIK.


That's not the case tho. KODI does have pass thru and bistreams properly, so the reliever handles it all, if you are missing this feature then something is wrong. But the only things would be the correct gpu driver, the HD audio driver and the correct WASPI driver selected in KODI I'm using a Radeon series 6.x card with no worries - same applies to the 5.x series tho they can get a bit hot.

I'm running all the formats off it including DTS:X and Atmos, so I hope that helps. My main driver is MPC-HC and windows as it's very rare that I need to upmix 2 channel.

cheers
 

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