Before reading any further, stop to picture in your mind what you think of when you hear the words "New Orleans music." I'll wait.

Now, what did you see? If you are like most of us, you probably envisioned an old Creole slouched in a chair with a clarinet in his mouth. Or perhaps a young brass band in Jackson Square playing for tourist dollars. Or a second-line funeral procession followed by hanky-waving, umbrella-twirling revelers. Maybe the swing of the Marsalis family, or the low-down f...