Joe Hall is a happy anomaly. In zydeco’s homeland of southwest Louisiana, Hall swims in a sea of zydeco players who mix their sounds with R&B, rap, and other mainstream influences. Hall, 47, prefers the tunes of his late grandfather, King Ned, an accordionist in an era when players sang in Creole French about loneliness, poverty, and death that came knocking way too early.

Traditional Creole music is why Hall became...