Sound therapy for Cats?

Is anyone familiar with it? Form what I gather it's in its experimental stages, but certain types of music can be comforting or calming to cats while other types might pick up a lethargic cat...

Similarly, the soud of running water like a brook or a fountain might be soothing to a crabby cat, while the sound of birds chriping might perk up a lazy cat...

I'm really curious about this, many Drug stores sell those sound therapy gizmos, white noise, pink noise, running water, wind through tree branches, chirping birds, rain etc...

Opinions?

I personally put on CD's I buy at the dollar store, which is soothing music. They have different types, Spa music, harp music, piano music, ocean waves with strings, spanish guitar... I usually always put on a CD when it's time to go to bed (Because I work third) and my cat Chickster seems to enjoy it. She's interested in instruments anyway, I played my mandolin for a bit and she got next to me and sucked her toe. My Boo (rip) hated it when I played any instruments but he didn't mind radio as long as it wasn't blaring.

Try some soothing classical or something quiet first, I'd say.