If the late New Orleans R&B singer Ernie K-Doe is remembered for anything besides his music, it’s without a doubt his repartee. “I’m not sure,” K-Doe was fond of saying, “but I’m almost positive, that all music came from New Orleans.” From Louis Armstrong to Louis Prima, Baby Dodds to Earl Palmer, Jelly Roll Morton to Dr. John, K-Doe wasn’t far off the mark.

But New Orleans has always been a place of extremes, as ragti...