Music: Down to Old Dixie and Back

It is not a commonplace river.

—Mark Twain, Life on the Mississippi

IN the Deep South, they have a saying that the closer you get to the Mississippi River, the better the music is. Down there, music lovers can easily tell whether a hot lick comes from 50 miles east of the river or 50 miles west; whether, in other words, it is East Texas blues, Delta blues or Georgia hill blues. If it gets much farther away than that, folks don't much care to know about it.

Small...