That's interesting. I wonder if, for a piece such as the Masked Ball, they would also supply the samples of the backward chanting?
One slightly creepy yet arresting piece that one. I've tried to do some processing on it to figure out what language it was - it certainly doesn't sound like English when it's run forwards. My ears pricked up big time when watching the film for the first time as I've used reversed samples of chanting and speech for years in my own stuff.
Also loved the stuff Pook did with Peter Gabriel - two supremely talented folk combined.
EDIT: From what I've been able to glean from a couple of quick searches, the chanting used in Masked Ball was a traditional Romanian Orthodox prayer (reversed of course)