Stereo to 5.1ac3-No Rear Left on Set Top: Looking for more Troubleshooting Options

[farmer dan]

First of all I thank all who have put their time, effort and talents into organizing and making available all the guides and layouts for working with bidules. I have come to really enjoy working with them and I really appreciate all the hard work people have done to make this a productive experience.

The symptoms I describe here apply to all the ac3 files I've generated in the last couple of days. To do my troubleshooting I used a BeeGee's song.

Using ursamtl's layout 5.1_VI-VSTandClassicReverb_ursamtl_041127 I created a six channel wave file, for which I then used BeSweet to encode to 5.1 ac3 (I used both the BeSweet GUI and AC3Machine just in case I did something in the command line parameters--results are the same.) Using DVDLab-Pro I authored a movie and burned it to DVD. When I played this movie on my set top, there was no sound in the rear left speaker.

The following lists summarized my troubleshooting results.

CHECK ALL PLAYERS WITH AC3 FILE FROM PRODUCTION MOVIE
Windows Media Player--all channels
Creative Player--all channels
PowerDVD--all channels
Winamp--all channels
Set top--all channels
[/list=1]
CHECK DVD PLAYERS WITH MOVIES COMPILED IN DVDLAB WITH AC3[list=1]
PowerDVD--all channels
Set Top--all channels
[/list=1]
CHECK DVD PLAYERS WITH PRODUCTION MOVIE[list=1]
PowerDVD--all channels
Set Top--all channels
[/list=1]
CHECK PLAYERS WITH CD CONTAINING MY AC3 FILE[list=1]
Windows Media Player--all channels
Creative Player--no rear left
PowerDVD--all channels
Winamp--all channels
Set top--no rear left or right
[/list=1]
NOTES[list=1]
Used default settings of BeSweet
I have AC3Filter installed
One DVDLab movie that I used had both an "all channels" ac3 file and the "no left rear" ac3 file. On the set top the first file played successfully and the other, obviously, had no rear left.
I haven't had the opportunity to test the DVD on another set top to eliminate mine as the culprit.
The digital information is in the file since it plays in some applications. The only possible culprits, using my limited knowlege, are the Creative Player and my set top.
My PC sound system, Audigy 2 Platinum Ex, is quite forgiving. Therefore, I don't know how sound my conclusions are.[/list=1]
Assuming that my set top is OK, I keep thinking about the following points and questions:[list]
Are there any BeSeet paramreters that I could change? (I've posted the log below.)
Does AC3 filter interfere with BeSweet? So far I have discovered no parameters or information that suports either side of this question.
Can I use AC3Filter in BeSweet? If so, would it do any good?

I'm sorry I have posted so much information. I am stumped. I can't see any other troubleshooting options. I'm looking for any and all suggestions and solutions.

Thanks,

Dan
BeSweet LogC:\Program Files\Besweet\BeSweet.exe -core( -input C:\Documents and Settings\Dan\My Documents\My Music\BeeGees\Stayin_Alive_Reverb_6ch.wav -output C:\Documents and Settings\Dan\My Documents\My Music\BeeGees\Stayin_Alive_Reverb_6ch.ac3 -logfilea C:\Program Files\Besweet\BeSweet.log ) -ac3enc( -b 384 -6ch ) -profile( ~~~~~ Default Profile ~~~~~ )

[00:00:00:000] +------- BeSweet -----
[00:00:00:000] | Input : C:\Documents and Settings\Dan\My Documents\My Music\BeeGees\Stayin_Alive_Reverb_6ch.wav
[00:00:00:000] | Output: C:\Documents and Settings\Dan\My Documents\My Music\BeeGees\Stayin_Alive_Reverb_6ch.ac3
[00:00:00:000] | Floating-Point Process: No
[00:00:00:000] | Source Sample-Rate: 48.0KHz
[00:00:00:000] +------- AC3ENC ------
[00:00:00:000] | Bitrate method : CBR
[00:00:00:000] | AC3 bitrate : 384
[00:00:00:000] | Channels Mode : 5.1
[00:00:00:000] | Error Protection: Yes
[00:00:00:000] +---------------------
[00:04:45:232] Conversion Completed !
[00:04:45:232] Actual Avg. Bitrate : 383kbps
[00:00:27:000] <-- Transcoding Duration

Logging ends : 01/05/05 , 08:41:49.

[ursamtl]

This is indeed a puzzling one. The only thing I see that comes to mind is AC3Filter. I had a problem with one app only, Media Player Classic (sound was mostly from front right speaker). Once I uninstalled AC3Filter completely and re-installed it, everything worked fine.

You might also try Zoom Player. There is a free version that gives a lot of of other players a lot of competition and it supports DirectX fiilters such as AC3Filter. I wonder if it will have the same problem with your file.

If AC3Filter isn't the problem, it might be a problem with DVDLab. I don't know this app at all so I can't help you much on that front.

Good luck!
Steve.

[farmer dan]

Hello again, Steve. Thanks for responding

I was afraid that I had obfuscated some possible conclusions by posting so much data. The real issue is that the AC3 files that I build myself won't play correctly on my set top player: if in a movie, there is no rear left sound; if on a CD, there is neither left nor right rear sound. My knowlege in this area is quite limited, and I don't know whether the lack of rear left sound from the Creative player is coincidental. If I just want to listen to the file, I can--on my PC. I was able to play, all channels, of a 5.1 wave that I made using the same bidule layout and the Creative player. However, I got no sound from a DVD. I'm going to have to "freshen up" on permissable DVD audio formats.

By the way:ursamtl wrote:...it might be a problem with DVDLab. I don't know this app at all so I can't help you much on that front.DVD Lab, both standard and pro, have a srictly "pass through" function for AC3. It is a wonderful authoring software. Incidentally, since the lack of rear sounds is common to both the Creative player and the set top, maybe the situation is not coincidental. Also, this would eliminate DVD Lab as the culprit.

Thanks again for your thoughts.

Dan

P.S. While I'm thanking you for things, let me also thank you for another one of your Canadian air masses that you Canadians so willingly share with us poor Iowans--it's cold and snowy here. :cool: :D

[KpeX]

Although I haven't carefully read your post, here's what I'd try:

First, do a search and download one of the AC3 test files floating around on the web, one of these files where a voice speaks in each of the channels in succession. Burn this to a DVD-RW or play via S/PDIF and test your system to make sure all channels are working correctly with someone else's AC3.

If that works, then try decoding the sample AC3 to a six channel wav and then encoding using the same method you do with your stereo to 5.1 conversion. Test this file in the same method and see if all channels are intact.

If the same problem occurs from simply re-encoding a 5.1 AC3 test channel, this means that the problem is occuring in your encoding step - do some more tests, post some logfiles, and we'll help you from there.

If the channels work when re-encoding a test AC3 stream, the problem is occuring in your stereo to 5.1 processing. Try some other methods and try to further narrow down the problem. Again post any stumbling blocks and we'll do the best to help troubleshoot.

Good luck,

[farmer dan]

KpeX thanks for the troubleshooting analysis. I did download an AC3 test file, named--amazingly enough--AC3TEST (I'll post a link to it in this thread later tonight or tomorrow. It's a great file.), and all my players and systems passed it.

However, I have solved the problem. I violated one of my own rules of troubleshooting: All options are equally probable until ruled out by hard data. I had ignored the actual file generation in bidule. As I was clearing the moisture deposited by the Canadian airmass that ursamtl sent to Iowa :eek: :D , I remembered that there was something in the BeSweet encoding of AC3 from WAV. Sure enough the channel sequence is not the same as the standard, which the bidules use. Here is the order change:
Standard--------BeSweet
FL------------------FL
FR------------------C
C-------------------FR
LFE-----------------SL
SL------------------SR
SR------------------LFE
[/list=1]I just re-wired the bidule and got the signals to the right speakers. I made the changes from the output of the 5.1-output module to the input of the Audio File Recorder. This is what I did:[list]
5.1-Output------Audio File Player Input
Channel 1-----------Channel 1
Channel 2-----------Channel 3
Channel 3-----------Channel 2
Channel 4-----------Channel 6
Channel 5-----------Channel 4
Channel 6-----------Channel 5
I put the resulting 6-channel wave directly in BeSweet, transcoded to AC3, compiled a DVD in DVD Lab Pro, and played it in my set top. The room was filled with balanced sound--sound which came from all the correct speakers.

Thanks again, KpeX. Your post reminded me not to violate my troubleshooting rules.

Dan

[eb]

@ farmer dan,
I have very kind ask to you
Could you check my samples with 6-channels ac3 5.1, AAc and Vorbis that were created from stereo source.
Samples named test+ac3+aac+ogg+mp3 .mkv
and 666test+ac3+aac+pgg+mp3 +mp2.mkv

Samples you can see on ftp://www.eb.enterpol.pl
user name www.eb.enterpol.pl
password eb

THese two sample were recorded on live from satelite digital tv to Xvid with 1 b-frame with cropping to 720x320 at the same time audio was converted to 6 ch LPCM.
Video was not processed latter but audio was processed to 6 channel AC3, AAC,OGG and mp3 and mp2.

I have only stereo system.

eb

[farmer dan]

The AC3 Test File, to which I referred above is availabe at

ac3filter.sourceforge.net/download/ac3test.zip

It's a VOB that plays a voice telling you what ac3 channel the sound is supposed to be in. If you want just the audio, you can demux it in IFOEdit and then use sound players.

@eb--I think I can do what you ask, but I may not be able to do it unitl this weekend.