concerto caledonia is a scottish baroque ensemble, specialising in the music of 18th century scotland played on period instruments, and directed by david mcguinness.
more recently, they have also performed works by contemporary composers, including frank zappa's 'echidna's arf'.
from their website:
"Thursday 24 October 2002
Yesterday's rehearsal bodes well for the rest of the week - we've tacked the baroque-d Frank Zappa Echidna's Arf onto the end of the bizarre Geminiani arrangement of Bonny Christy to make a medley of 'inappropriate music' to start the second half."
other parts of their diary talk about performing the zappa piece.