Conductor Giancarlo Guerrero is on a mission with the Nashville Symphony to expand the contemporary American concerto repertoire. Each of the three works on their new release spotlights a different facet of the relatively underexplored brass instrument family. Brad Warnaar’s Cornet Concerto is a witty and heartfelt homage to the rich heritage of 19th-century band music. Chick Corea’s Trombone Concerto, …