Sad songs made happy: The amazing art of turning minor-key songs major

"In Western music, there's nothing that says 'sad' like a minor key," explains the Exploratorium science museum. You don't have to be up on your music theory — or have synesthesia — to recognize when a song is written in a minor scale, and the difference between major and minor is pretty clear when you hear a minor song transposed into a major key. (Without getting into too much complex music theo