VLC HowTo/Extract audio
VLC can extract audio from most sources with no loss of quality, because there is no re-encoding of the content.
The way to do this for DVD video is (on Linux):
vlc --no-sout-video dvdsimple:///dev/scd0@1:1 :sout='#std{access=file,mux=raw,dst=./file.ac3}'
See Also
- How to Rip DVD Audio to MP3 Using VLC Media Player, Edited by AudioDude and 2 others, WikiHow.com