Jennifer Higdon's Viola Concerto premieres at Curtis Chamber program

The Curtis Chamber Orchestra dished out a big program for its appearance at the Library of Congress on Saturday, but the main event (and what packed the house) was the world premiere of Jennifer Higdon's Viola Concerto, commissioned by the library and played by violist Roberto Diaz (now president of the Curtis Conservatory and formerly principal violist of the National Symphony Orchestra under Mstislav Rostropovich) on a Guarneri instrument that has been on loan to the library since 1977.