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-- Questions about AC3 audio and Dolby Digital (http://www.vcdhq.com/forum/showthread.php?threadid=50624)

Questions about AC3 audio and Dolby Digital

I have a few questions about AC3 audio and Dolby Digital and encoding. I just recently started burning DVD-R (new dual layer drive, but only using 4.7 media right now) and have been converting Xvids using Tmpgenc and then authoring and burning with Tmpgenc DVD Author. the video quality has been quite good, no problems there, but the AC3 audio has me confused. Basically, the audio works fine as well, but when I put the disc in my stand alone, it reads the dvd-r audio as Dolby Digital. Okay, good so far. But for some reason my reciever, a Kenwood VR-6050, which does everything from Dolby Digital EX to CSII, only picks up two channels, the left and right (both front). No center, no rear channel. And this is on Dolby Digital. Now I've messed with this a little so far, and even changed the audio settings on my stand alone (a samsung which plays just about anything other than xvid/divx, and all media) from PCM to bitstream and back. On bitstream, I get the Dolby Digital, which both the DVD player and reciever pick up, but only with the two channels. On PCM, the DVD player picks it up as a Dolby Digital (the Dolby Digital lights up on the front) but the reciever does not. I use CSII instead, which is fine, since it allows me to use the center, front, rear, subwoofer, and surround center rear speakers all at once, so it sounds great. But I'm curious as to what would cause this. Is it my encoding (more than likely) and if so, what settings am I missing (I've seen 2 channel stereo as a setting, more than likely thats what' causing the problem, right?). Is it the AC3 codec and there's nothing I can do about it, or should I check my dvd player/receiver setup? Any one who has any ideas or suggestions on how to fix this, or improve it, please post and let me know.

Otherwise, the movies are coming out great, I'm lovin' DVD-R!

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The AC-3 you get in XviDs should be the untouched AC-3 stream from the original ripped DVD, so no encoding is necessary. I assume the stream can be just ported straight across to your DVDR.

Extract it with VirtualDub direct stream copy (ignore any complaints it will have, it doesn't support AC-3 natively), rename the extracted .wav to .ac3, then try loading that into your DVD authoring proggie with your m2v video.

AC3/Dolby Digital is just a format. It can be anything from mono, stereo to full 5.1 surround. Try loading the ac3 file into something like SoftEncode and see if it's really 5 channels.

Thanks, both of you have good ideas, I'm going to try both later. Anyone else?

EDIT:

I did a search yesterday on dvdrhelp.com, and didn't find this, but then I did another search and got this tutorial:

http://www.videohelp.com/forum/userguides/186739.php#1

Why I didn't see it or get it the first time, I don't know, but I am in the process of following it right now, with both xvids being converted in tmpgenc as we speak. I'll author it later and see what the results are and post them here.

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