As a performer, Mann played the recorder and double bass professionally. His son, Adrian, is principal bassist and manager of the Fort Wayne Philharmonic.
Mann was also a choral conductor and led the Bach Choir of Bethlehem in Pennsylvania and the Cantata Singers in New York. He edited the American Choral Review and a number of papers for collected editions of Fux, Handel, Mozart and Schubert, according to the Times.
Mann was born in Hamburg, Germany, in 1917; his mother was the keyboardist and writer Edith Weiss-Mann. He studied at the Milan Conservatory in Italy and at the Berlin Hochschule f‹r Musik.
He emmigrated to the United States with his mother to escape the Nazis and continued his education at the Curtis Institute and Columbia University.