"Play some bossa nova,” hollers a belligerent man from his barstool. His tawdry female companion adds to the racket just as the band on stage descends onto the closing bar of its set’s second song. In the moment that follows, a tense air fills the room. For the French Quarter crowd, it isn’t the outburst that takes them by surprise, it’s the scene: Irvin Mayfield’s Jazz Playhouse, the city’s swankiest jazz joint.

[caption id="attachment_316052" align="align...