Is it possible to take a concert video, and burn off the 5.1 sound to DVD-Audio ? The DVD audio plaver in my car play DVDA and DTS audio discs, so I'm wonderinding if there isn't a way (hopefully fairly simple) to extract the audio portion of a concert and burn to a multi - channel DVDa disk ?
Yes, this is perfectly possible.
DVD-Audio uses PCM files though, not Dolby Digital or DTS so you will need to decode them first. As DD files are heavily compressed with a lossy technique similar to MP3, there will be a quality price to pay.
Extracting the Audio is easy. You just use either DVD Audio Ripper, http://www.imtoo-dvd-ripper.com/dvd-audio-ripper.html, although I suspect that this does NOT decode Multichannel files. Not sure about that, so may be wrong.
Best choice is DVDDecrypter. This will rip the multichannel files. You will still have to decode them into WAV files though. I believe this can be done with BeSweet, but am not sure. I use a different method, as I am lucky enough to own Nuendo & it's Dolby Digital Encoder. Try searching these forums about this one, or else you could try http://forum.doom9.org/forumdisplay.php?s=&forumid=11 where they have various guides posted for you to do just this.
Then you will need a DVD-Audio authoring tool, either WaveLab or discWelder will do the job for you.
I am on much more solid ground there, so when you have the WAV files ready to go, give me a shout & I will help you through the Authoring phase.
