The searching I've done shows that soundjuicer should have a button to edit profiles and allow setting the quality of ogg encoding.
I don't have that button in the version on my system. Is this a bug, or has the application changed?
apt-cache policy sound-juicer
*** 3.4.0-3 0
500 http://us.archive.ubuntu.com/ubuntu/ quantal/universe amd64 Packages