This month, longtime Academy team member David Nerattini, AKA Little Tony Negri, explores the orchestral side of jazz and the many albums that feature choirs and vocal arrangements as their main proponent. From Duke Ellington and Billy Strayhorn to Kamasi Washington, via Dizzy Gillespie, Max Roach, Horace Silver, Mary Lou Williams, Archie Sheep and Jack McDuff, we hear voices stacked in at least eight layers of harmonies, creating some of the most forward-thinking music of the past century.