southern nights

Hi!

Don't know if this is the right category to put this thread on, so please correct me in the right direction if it's not!

I've been thinking about this one for a while but can't figure it out..

What's the main vibrating, thin, flangy, rotary vocal effect Allen Toussaint uses on his version of the song Southern Nights? Or can somebody of you figure out the effect chain, or is this some kind of special effect i don't know about?

It's cool, for sure!

Torsten