• 1
  • 46
  • 47
  • 48(current)
  • 49
  • 50
  • 54
Linux AudioEngine testers - Linux only
Now it seems like all sources (dts, ac3) with more than two channels are downmixed to stereo when not bitstreaming. I'm not sure if this is a bug, or default behavior...
Reply
Well as you said you have a stereo system, isn't this what you want? You can't play 6 channels through 2 speakers without something happening - either you get 2 of the 6 channels (not what you want) or you get a downmix.
If I have helped you or increased your knowledge, click the 'thumbs up' button to give thanks :) (People with less than 20 posts won't see the "thumbs up" button.)
Reply
(2013-01-10, 05:32)nickr Wrote: Well as you said you have a stereo system, isn't this what you want? You can't play 6 channels through 2 speakers without something happening - either you get 2 of the 6 channels (not what you want) or you get a downmix.

The phrase 'when not bitstreaming' should have given it away, but I got my 7.1 receiver back, and tested the Pi with that. Obviously what you described is what has to happen when dealing with stereo output.

Reply
Ahh I see, that explains it.

So I am unsure what your problem is now? aac 7.1 not bitstreaming? aac 7.1 not mapped correctly? Sorry if I seem confused. Perhaps a restatement of your difficulty will clarify my fuzzy synapses.
If I have helped you or increased your knowledge, click the 'thumbs up' button to give thanks :) (People with less than 20 posts won't see the "thumbs up" button.)
Reply
(2013-01-10, 05:46)nickr Wrote: Ahh I see, that explains it.

So I am unsure what your problem is now? aac 7.1 not bitstreaming? aac 7.1 not mapped correctly? Sorry if I seem confused. Perhaps a restatement of your difficulty will clarify my fuzzy synapses.

LOL, so there are a couple of problems:

1) All 7.1 AAC is silent, whether connected to a 7.1 receiver via the TV's analog output to a stereo. (AAC cannot be bitstreamed; never heard of a receiver that can decode AAC from HDMI or SPDIF.)
2) All multichannel audio (all flavors of AC3 and DTS; 5.1 AAC) is downmixed to 2.0 if decoded onboard rather than bitstreamed.

All this is with OpenELEC 3 RC on a Raspberry Pi with XBMC 12.0-RC3. I have changed the audio output between 2.0, 5.1, and 7.1 in the Audio part of Settings > System, to no effect. I'm not sure if it's an xbmc issue, an rpi issue, an openelec issue, or what.

Reply
@LastSilmaril

Paste a screenshot of you xbmc audio settings menu

and so thet we are clear on this, Where is your HTPC connected to - TV? Receiver?

uNi
Reply
If you read back a few posts it is a receiver.

Silmaril -
Quote:2) All multichannel audio (all flavors of AC3 and DTS; 5.1 AAC) is downmixed to 2.0 if decoded onboard rather than bitstreamed.
if your computer is decoding a 5.1 stream on board, it has some choices:

1. stereo LPCM via spdif or HDMI
2. stereo analogue via two analogue ouptuts (possibly one 3.5mm stereo plug like you have on your mp3 player)
3. 5.1 via a soundcard with 6 analogue outputs, one per channel, with 6 analogue connections to your receiver (possibly 3 3.5mm plugs)
4. 5.1 LPCM via HDMI (not spdif) to your receiver.

Which are you wanting to achieve? (And what you can achieve depends on your hardware, OS and drivers.)

Oh and there are receivers that accept aac streams, although whether they do 7.1 is unknown to me.

If I have helped you or increased your knowledge, click the 'thumbs up' button to give thanks :) (People with less than 20 posts won't see the "thumbs up" button.)
Reply
(2013-01-10, 09:44)uNiversal Wrote: @LastSilmaril

Paste a screenshot of you xbmc audio settings menu

and so thet we are clear on this, Where is your HTPC connected to - TV? Receiver?

uNi

I'm sorry for the confusion.
Sometimes connected to a TV (in one room) sometimes to a receiver/home theater (in a diff room). Either way a) 7.1 AAC is silent and b) multichannel is always downmixed to stereo, except when bitstreaming AC3 and DTS.

When connected to the TV this is my audio setting:

Image

When connected to my receiver:

Image

System info:

Image

Usually, of course, I'll have DTS and AC3 set to bitstream when used with my receiver; I shut off bitstreaming to see if they would be downmixed to stereo PCM, and they are.

nickr: I'm trying to achieve PCM via HDMI to my receiver. So, 5.1, 7.1 via HDMI. I know that my receiver can handle this since it's set up that way with my fat PS3 (which can't bitstream TrueHD or DTS-MA).

(2013-01-10, 11:08)nickr Wrote: Oh and there are receivers that accept aac streams

Really? Can you show me one? Because that would be cool...
Reply
What your receiver can do, is one thing what your HTPC hardware can output is another. So check what your hardware both HTPC and Receiver can do before going off in a never ending mission.

Setting look ok presuming what I said above is possible for your HTPC and receiver or HTPC and TV combo can work as you expect or think they will

uNi
Reply
So this seems to be a Pi related issue (took me a while to find), and OpenMAX needs to be set to output multichannel audio if given it (depending, I suppose, on the configuration specified in System > Settings > System > Audio).
http://forum.stmlabs.com/showthread.php?pid=35504

It seems capable but in need of a patch. Thanks for entertaining my questions guys.
Reply
Well here is my screenshot (frodo RC3) which shows a whole lot more options than yours.Image

Ahhh hold on I see you are on an arm system (your kernel string gives it away). Is this a Pi or something?
If I have helped you or increased your knowledge, click the 'thumbs up' button to give thanks :) (People with less than 20 posts won't see the "thumbs up" button.)
Reply
(2013-01-10, 20:33)nickr Wrote: Ahhh hold on I see you are on an arm system (your kernel string gives it away). Is this a Pi or something?

LOL, yessir
Reply
Well I entertained the idea this was hardware related or user related, Hence why I was asking mostly rhetorical questions... If it turns out to be a problem with patching on such a new platform Im not surprised. Im surprised it works as wll as it does atm though! Just goes to show the sheer amount of work devs have put into it...

uNi
Reply
So the question is, how do enable the 'Multichannel LPCM capable receiver' setting and the underlying audio mixer stuff? The link to STMLabs above suggests that omxplayer needs to be modified as well...
Reply
How about you ask there?

Or ask in RPI subforum I doubt many ppl have a RPI to begin with.

uNi
Reply
  • 1
  • 46
  • 47
  • 48(current)
  • 49
  • 50
  • 54

Logout Mark Read Team Forum Stats Members Help
AudioEngine testers - Linux only4