Convert Multi-Channel AAC/FLAC

[Guest]

Here's a discussion about this.

https://answers.microsoft.com/en-us/windows/forum/all/soundbar-connected-to-pc-via-optical-cable-only/19b86b20-aa81-44af-b62b-44f4a70ae49b

Yes, he's trying to use optical, which I believe is the issue here. The 'splitter' has an optical port that must be sending a signal back down the HDMI, notifying the OS. Once Widows gets that, it behaves as though you've connected an optical cable to the output sound device. Windows knowing that it only supports 2 channel uncompressed audio, limits the options to two channels.

 

With regard to the SONOS soundbar, it appears that it also supports ARC. So if you forget about object based audio (Atmos etc), and reconfigure, you my have better luck.

https://www.sonos.com/en-us/guides/beam

 

Additional information on spdif/optical

https://learn.microsoft.com/en-us/windows-hardware/drivers/audio/s-pdif-pass-through-transmission-of-non-pcm-streams

I would follow Softworx' suggestion, and try connecting to other devices. I would try the ARC connection first, and not use the 'splitter'.

 

 

[softworkz 5066]

But he doesn't connect the soundbar via an optical port, and also an optical port has no way of sensing whether something is connected to it or not.

Returning to what I stated above: The extractor supports uncompressed multi-channel audio and it supports switching the channel layout. If it would be true that the existence of the optical port would cause windows (or any other source!) to see it as 2-channel audio only, then the channel-layout-switching feature and the feature of supporting multi-channel uncompressed audio would be moot (non-existent).

So I rather expect that in cases of multi-channel uncompressed audio, the optical port just doesn't output anything.

And if you want to use the optical port, you set the audio channels to 2.0.

Edited December 25, 2024 by softworkz

[softworkz 5066]

What's also possible would be that the soundbar reports that it support only stereo (when uncompressed) and reports this back via HDMI, and the setting on the gadget is acting more like like a maximum channel count setting. Obviously it makes no sense when the gadget reports 8 channels but the soundbar cannot take it.

But it makes sense to limit channels to 6 on the gadget even though the soundbar would take 8 as well.

I hadn't mentioned this before because the specs of the soundbar give no indication that it would support only stereo (uncompressed)

[Guest]

And is why I ultimately suggested trying ARC instead of eARC. That would hopefully support 5.1, depending on the TV. I think the chase for Atmos needs to be given up, and pursue 5.1. Without the 'gadget' in the chain, and connecting directly through the TV with ARC, might resolve the struggle. Or, stop using multi-channel AAC. I don't see a possibility to achieve all that is desired. 

There is only one other option that I won't repeat again 

[softworkz 5066]

13 minutes ago, generiq said:

And is why I ultimately suggested trying ARC instead of eARC. That would hopefully support 5.1, depending on the TV. I think the chase for Atmos needs to be given up, and pursue 5.1. Without the 'gadget' in the chain, and connecting directly through the TV with ARC,

He doesn't have a TV, he's got a projector which doesn't have ARC neither eARC. And the soundbar doesn't take normal HDMI as input, only eARC. This eliminates a lot of options unfortunately.

And Atmos is not really a problem since that is actually working with passthrough (carried over TrueHD). But this doesn't need the Atmos software on the PC, which isn't involved in any way when playing videos with Atmos. (he had confirmed both already).
The Atmos software - from my understanding - is rather meant to "enhance" any non-Atmos audio for playback on an Atmos system.

Edited December 25, 2024 by softworkz

[Guest]

11 minutes ago, softworkz said:

He doesn't have a TV, he's got a projector.

AH I forgot about that! 

I really don't see a solution for multi-channel AAC to keep it multi-channel with what he's got. I just don't think it's going to work. 

I messed around with an Arcana HD Fury a while back. It just doesn't do what you want it to do. I suppose improvements have been made since then

https://hdfury.com/product/4k-arcana-18gbps/

Edited December 25, 2024 by generiq

[softworkz 5066]

There are three possibilities:

1. The soundbar can handle uncompressed only in stereo, and that's why you don't see a 5.1 speaker layout in the speaker configuration on Windows
2. The gadget can't do what it's promising => hence no 5.1 option
3. The Atmos software wants to be in charge of all multi-channel configs and hides the 5.1 speaker layout

1 and 2 cannot be remedied.

3 can be tested

• either by using a different computer as the source, to see whether there's a 5.1 layout in the speaker config then
• or by uninstalling the Atmos software (but then it depends on whether it would uninstall cleanly)

[Guest]

5 minutes ago, softworkz said:

There are three possibilities:

1. The soundbar can handle uncompressed only in stereo, and that's why you don't see a 5.1 speaker layout in the speaker configuration on Windows
2. The gadget can't do what it's promising => hence no 5.1 option
3. The Atmos software wants to be in charge of all multi-channel configs and hides the 5.1 speaker layout

1 and 2 cannot be remedied.

3 can be tested

• either by using a different computer as the source, to see whether there's a 5.1 layout in the speaker config then
• or by uninstalling the Atmos software (but then it depends on whether it would uninstall cleanly)

Yup! SONOS probably expected everyone to use audio passthrough. 

[softworkz 5066]

32 minutes ago, generiq said:

Yup! SONOS probably expected everyone to use audio passthrough. 

The docs say otherwise. Same like all contemporary (not age-old) TVs support uncompressed multi-channel audio.

That's also how Xbox prefers to output audio: decode compressed multi-channel formats internally and send it uncompressed to the TV, unless the TV supports Atmos, to which it can even encode.

Anyway: the point is that it has become kind of common knowledge that a player has to do AC3 encoding because HDMI devices rarely support multi-channel AAC audio. 
The latter is true, but the conclusion is wrong (in case of Windows, it's only true for some apps which cannot change the audio): AC3 encoding is generally not needed because almost every HDMI device supports multi-channel uncompressed audio and that's by far better than recompressing as AC3 (which is much worse than AAC). 

This might be one edge case, where there's no other way, but providing it as an option would make everyone enable it, having it "learned" from other apps.
It's the same problem for audio passthrough: Everybody thinks that this is needed, but MPV can decode everything but Atmos (and DTS-X iirc), which means that passthrough isn't needed for all other formats. 

In other words: If there was an AC3-encode option, everybody would have enabled it (causing inferior audio), but now there is none and it's working for everybody but one (this).  Will think after the holidays about how to deal with this.

Edited December 25, 2024 by softworkz

[Guest]

Yeah, so many people are beguiled into believing they can hear it, if the options are enabled. In reality, most can't actually hear the difference. Soundbars supporting object based audio always make me shake my head in wonder. Marketing. 

Jeeb recently stated that none of the active mpv developers have bitstreaming capable hardware. So the enduser is required to do their own research on the capabilities of the hardware they are using.