DVD audio through S/PDIF?

Kua

Kua

Kua

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My audio is through the S/PDIF port to a DAC and I'm trying to play a DVD. I've tried installing AC3 filter (although I'm not totally clear what it does) but still I have popping and fuzz whenever I try to play a DVD. I've tried any number of media players. This is driving me potty.
 
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I wondered if it was conflicting with my sound driver. But I don't get any sound at all when I don't have the sound driver installed. I have no idea why it needs to be installed...its for my sound card, which I'm completely bypassing.
 
well your not completly bypassing the sound card when using s/pdif, without drivers your pc wont even know its got an s/pdif port

It could be a driver issue thats causing the popping and fuzz, maybe try a different version?
 
this page..

http://www.kellyindustries.com/sounds.html

has some test files.. pls can you test and report back which (if any) work ok, and which (if any) have the same issue

im guessing that the stereo stuff will work fine and the DTS and Dolby Digital will produce the same error.

Ac3filter can probably be configured to fix the problem you are having by downmixing to stereo, in fact some dvd software can also do the same - what dvd doftware have you got?
 
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cokecan72 said:
well your not completly bypassing the sound card when using s/pdif, without drivers your pc wont even know its got an s/pdif port

It could be a driver issue thats causing the popping and fuzz, maybe try a different version?
Click to expand...

Ah. I thought there might be some holes in my understanding :) . I've definitely got the correct driver installed. And its only with DVDs that I have the issue (I'm not sure what format they're normally in).

masterluke said:
this page..

http://www.kellyindustries.com/sounds.html

has some test files.. pls can you test and report back which (if any) work ok, and which (if any) have the same issue

im guessing that the stereo stuff will work fine and the DTS and Dolby Digital will produce the same error.

Ac3filter can probably be configured to fix the problem you are having by downmixing to stereo, in fact some dvd software can also do the same - what dvd doftware have you got?
Click to expand...

I'm downloading those files now - will report back later.

Re. DVD software. I'm using PowerDVD - with that the problem is tolerable but annoying. In VLC its just static IIRC and Media Player Classic isn't a great deal better.

In PowerDVD I've set it up to use stereo (in Configuration -> Speaker Environment). When I set that same option to "Use SPDIF" (which seems the logical thing to do) all I get is static.

EDIT:

Pro Logic - Fine
Dolby Digital Encoded (5.1 WAV file @ 44.1kHz/16-bit Stereo) - Static
DTS (WAV @ 44.1kHz/16-bit Stereo) - Static
Dolby Digital Encoded (AC-3 5.1 Surround @ 48kHz/16-bit) - Haven't been able to play this one yet. Let me know if its important.
 
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I has solution! It sounds really stupid and obvious (mostly because it is) but I opened up AC3filter config clicked "Auto" for "SPDIF/DTS mode" and clicked "Use SPDIF". Hurrah for fiddling around. Oh and the Audio Device in my media player has to be set to "stereo", i.e. not SPDIF.

EDIT: Scratch that. It still doesn't sound quite right :S . It is set to 2.0 in AC3 Filter btw.
 
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As far as i can see your results are pretty much as expected.. you have a stereo DAC so it cant reproduce the dolby digital or DTS audio from the test files or DVD's - and from what you describe it works if you downmix the audio to stereo in the dvd software.

Sounds to me like everything is working as it should.

One thing to look out for is that you may be getting only the 2 front channles depending on the config.. that will sound wierd.. you need to make sure all 6 channels are getting downmixed to stereo.
 
Can someone tell me how to set up AC3 filter? I'm stumped.

Here's how it is at the moment and I'm still getting a lot of popping noises:

ac3w.jpg


Honestly I think its my SoundMax driver which has been trouble from day one. I still really can't understand why I need it installed for me to use S/PDIF: I suppose S/PDIF doesn't have its own driver and its integrated into the audio driver. I wonder if it would be better to install my Creative sound card and use the Creative sound driver - but when I had it installed in the past I wasn't able to use S/PDIF at all. This problem just makes me want to weep. The way I'm getitng frustrated over this I feel like a super emotional adolescent all over again :D .

To be honest it seems to make no difference whether I use AC3 filter or not...

I've tried the CCCP encoder pack. But I don't know if I need that or if it will help. Honestly I find this all very confusing. But I tend to think its just my driver and this can't be helped. And that the only solution is a new motherboard - and what the hey? in that case I might as well buy a whole new PC!
 
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masterluke said:
As far as i can see your results are pretty much as expected.. you have a stereo DAC so it cant reproduce the dolby digital or DTS audio from the test files or DVD's - and from what you describe it works if you downmix the audio to stereo in the dvd software.

Sounds to me like everything is working as it should.

One thing to look out for is that you may be getting only the 2 front channles depending on the config.. that will sound wierd.. you need to make sure all 6 channels are getting downmixed to stereo.
Click to expand...

I'm not sure what you mean by this. Six channels? As in 5.1? Is Dolby Digital for six channels? How do I make sure they're all downmixed to stereo?

I'm going to run away and cry again.
 
The reason I would say is your DAC does not support Movie formats, IE AC3, DD or DTS So no point clicking AC3 passthrough as it will not process a bitstream signal from a DVD.
It needs to be fed PCM signal only. So a down mix and NOT passthrough is required from the DVD software, or driver set up.
It's working as it should, as a stereo only DAC.
 
9designs2 said:
The reason I would say is your DAC does not support Movie formats, IE AC3, DD or DTS So no point clicking AC3 passthrough as it will not process a bitstream signal from a DVD.
It needs to be fed PCM signal only. So a down mix and NOT passthrough is required from the DVD software, or driver set up.
It's working as it should, as a stereo only DAC.
Click to expand...

Doesn't help I'm afraid. To make a DVD watchable at all I've had Power DVD set to stereo rather than UseSPDIF - which I think is what you're recommending. I also set AC3 filter to "Output SPDIF as PCM" - it doesn't make any difference. Gah!
 
You're not having any problems, this is completely normal. If you set your software to use S/PDIF it will bitstream the AC3/DTS track which your DAC cannot decode. LEave it at stereo and your S/PDIF is functioning anyway outputting a digital stereo signal.
 
AbsenceJam said:
You're not having any problems, this is completely normal. If you set your software to use S/PDIF it will bitstream the AC3/DTS track which your DAC cannot decode. LEave it at stereo and your S/PDIF is functioning anyway outputting a digital stereo signal.
Click to expand...

Yes but if I leave it at stereo I get a lot of intereference...
 
Ah I didn't get this from your posts. In the control panel for your soundcard or the windows one find the output format setting for S/PDIF and make sure it's set to stereo then play with the bitdepth and sample rates.
 
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