Absolute Anime

The Tenchi Universe theme, in both Japanese and English, is sung by a group called SONIA (or Sonia). I've looked and looked for information on this group, trying to find out who the singers of this group are, but to no avail. Does anyone know who the members of SONIA are?

if you type this song into youtube, you actually see the band performing this song live.
pretty cool.

i must watch or its ok