Duke Ellington's work has long been recognized as the very essence of his art. Much less attention has been devoted to his use of vocalists, though the band's nearly half-century history is studded with the names of singers of singular ability, including Adelaide Hall, Ivie Anderson, Betty Roche, Joya Sherill, Kaye Davis, Jimmy Grissom, Alice Babs and Anita Moore.

Tomorrow, Howard University's Cramton Auditorium will be the scene of "Ellington Revisited," featuring former Ellington vocalists Al Hibbler, Jimmy McPhail and June Norton. A benefit for WPFW-FM , the program will also feature performances by tappers Bunny Briggs, who frequently danced with the Ellington band, and Brother Black; pianist John Malachi; and the Charlie Hampton Big Band, which will offer two sets of Ellington instrumentals.

Hibbler, who was born blind, first met Ellington in 1935 when he was studying voice at the Conservatory for the Blind in his native Little Rock, Ark. "I had an audition with him," says Hibbler, "and I was drinking pretty heavy. Ivie [Anderson] wanted to take me and look after me, but Duke said, 'I can handle a blind man, but a blind drunk, I can't make it.' " It was nearly a decade later that Ray Nance smuggled Hibbler onto the bandstand while Ellington wasn't looking. That was 1943 and he stayed until 1951.