Leon Redbone lies somewhere between a circus carnie and a quirky folk singer. The man is recognized as much for his odd appearance (he has sort of a 1930s eccentric socialite thing going on) as for his smooth baritone. Redbone originally gained fame by performing “Ain’t Misbehavin'” on Saturday Night Live and has since sustained his career — which blends jazz, folk and ragtime — by covering standards, obscurities and his own leisurely Dixieland shuffles. Yet the mystery man, who refuses to divulge personal information, still ends up in the strangest places (Adam Sandler’s wedding and composing the theme to Mr. Belvedere, among them). Redbone prides himself on his eclectic live show, which blends performance art and comedy with music that provides a perfect soundtrack to the lazy final days of summer.