I used to have a Siamese cat who would try to kill me when I sang to him, although I'm sure my wife would empathize with the cat. There is not a cat alive that wants to listen to me sing "Tiptoe Through the Tulips," so I don't know about the falsetto theory. Each of my cats has her own song, and I do sing to them when it's time to cuddle. The young one, whose ears are probably more sensitive, doesn't much care for that, although she doesn't try to kill me. The two older ones seem to like it, though. They are sisters from the same litter. One of them, in particular, if I start singing her song, she will lift up her head and look at me, anticipating that I am going to come pick her up. Her sister sometimes goes in the opposite direction, as if to say, "Oh no! Not that!" I have not noticed that they particularly care for any commercial music one way or another, although they hate anything that's loud.