There is an interesting interview on NPR's Science Friday show, right now. I am sure they will have a link to a recording of it today. There is more about the program HERE. Here's the blurb:

How Music Works

From pitch to frequency and harmony to rhythm, how do sounds become music? What separates Bach' s Prelude in C Major from Led Zeppelin' s Stairway to Heaven? In this segment, Ira talks with Dr. John Powell, a physicist and composer. He's the author of the new book "How Music Works: The Science and Psychology of Beautiful Sounds, from Beethoven to the Beatles and Beyond.