A year ago, Jim James of My Morning Jacket joined Elvis Costello, Marcus Mumford of Mumford & Sons, and other stars to set never-released Bob Dylan lyrics from his 45-year-old "Basement Tapes" to music. James immediately noticed that his interpretation of a particular Dylan song didn't sound like anybody else's version. "Elvis would write bashing punk lyrics to the same set of music I wrote a slow, soft love song to," James, 37, recalls by phone from his Louisville, Kentucky, home. "It was funny to see how those same words affected us so differently. It made me question: 'What is a song?' "
