How do I get stereo through SPDIF? (1 Viewer)

[timibloodflo]

First time post here.... MediaPortal rocks !!!

I do have one problem however - I am having trouble getting stereo (I think it needs to be uncompressed) to pass through HDMI to my AV receiver (ONKYO 875). Essentially what I want to do is let my AV receiver apply its filters on this stereo output (Neo surround, etc). At the moment I have my system passing through DTS and it is picked up by the receiver appropriately. Unfortunately, anything that I play that has a stereo audion track in media portal, it is being passed to my AV receiver as a multichannel PCM stream. The unfortunate part of this is that although it is 'multichannel', there is only sound on my L & R speakers. The other side effect is that because it is multichannel PCM already, my AV receiver cannot apply any surround sound effects to it.

Now I did have it working briefly a week ago, however it seems to have stopped working how I want it.

My setup at the moment includes media portal 1.0, with FFDSHOW, SPDIFER and Haali media splitter. I have tried all of the settings that I thought would allow me to pass this true stereo signal to my AV receiver, however I am having no luck at all.

Can anyone point me in the right direction and what settings I might need to look at? I want to do as much audio decoding in my AV receiver as possible, and as little through software.

If you need any more information to help solve this problem please let me know.

 

[Owlsroost]

Make sure the speaker settings in the Windows/sound card control panel and (if you use it) the FFDShow audio decoder 'mixer' settings are set to stereo (or 2-channel or 2/0/0).

Basically, Windows uses the sound device speaker settings as a reference and will upmix/downmix the audio to match the speaker layout.

Tony

 

[timibloodflo]

kk ... thanks for the reply, much appreciated. I will update you about my situation.

I had the windows speaker option set at 5.1 initially, and that's what produced the problem I described in my first post (i.e. all stereo sources were being output as multichannel PCM, with sound only in the L and R speakers).

So I changed my windows XP settings to stereo speakers and it correctly outputs my stereo soundtracks in stereo, and my AV receiver is able to apply it's surround sound processing on these stereo sources as I wanted.

Problem is..... now it doesn't seem to be handling my 5.1 soundtracks properly. It seems as if it is taking the 5.1 channels and only outputting the L + R channels to produce a 'stereo output'. Ideally what I would want in this case would be to output this 5.1 sound source as a multichannel PCM (where my AV receiver simply plays the true surround as it should be) and normal stereo sound sources as a plain stereo output (so that my AV receiver can apply its surround sound processing on the stereo input). Now if I put my WinXP speaker setting back to 5.1 it outputs this 5.1 soundtrack properly but that takes me back to my initial proble,

So ..... is there any way that I can overcome this problem? Is there a way 5.1 (not DTS track) can be output as a DTS or alternative surround sound signal or is there a better way to overcome this? I have lots of my sources encoded with DTS and Dolby Digital 2.0 tracks and these are correctly passes straight through to my AV receiver regardless of what I set my WinXP speakers as. Alternatively - is there a way to output stereo sources as Dolby Digital 2.0 and will that help overcome this problem.

Any and all help is appreciated btw !!

 

[Owlsroost]

The FFDShow audio decoder can also encode to AC3, upmix/downmix and switch presets according to numbers of input channels etc. so it should be able to do what you need - if you can work out how to do it....

I run multi-channel analogue into my receiver, and use FFDShow to upmix stereo and downmix 5.1 to my 4 channel speaker setup, with the upmix or downmix preset automatically selected according to the number of input channels.

If you need more pointers I'll upload some FFDShow presets/setup screen shots.

Tony

 

[nabster]

Hi have you tried using different codecs had similar problems with pass through audio using ffdshow audio ,after many months of head scratching got rid of ffdshow audio and switched to
AC3Filter and hey presto no more problems.

 

[Der_Bub]

The FFDShow audio decoder can also encode to AC3, upmix/downmix and switch presets according to numbers of input channels etc. so it should be able to do what you need - if you can work out how to do it....

I run multi-channel analogue into my receiver, and use FFDShow to upmix stereo and downmix 5.1 to my 4 channel speaker setup, with the upmix or downmix preset automatically selected according to the number of input channels.

If you need more pointers I'll upload some FFDShow presets/setup screen shots.

Tony

Hi Tony,

I'm looking for a similar solution for months and didn't get a solution for this:

• If the signal is a DD (5.1) it should be sent to the receiver as it is.
• If it's only a 2 Channel stereo it should be send analogue to the receiver, so he can handle the upmix.
• And finaly (with analogue stereo) it should be normalized (because of the volume with advertesment)

It seem's that your solution it pretty near my wishes, so I would very pleased to see your configuration (MP, Windows and ffdshow)!

Thanks allot!

BERND