Contemporary sextet eighth blackbird stars in this Sounds of the Times event, which highlights the works of three living American composers. Steve Reich’s Pulitzer Prize-winning Double Sextet, originally commissioned for the Chicago-based ensemble, opens the concert with a gripping duel of pianos and vibraphones. Also written with sextet in mind, Jennifer Higdon’s On A Wire features each member of the ensemble soloing with the orchestra throughout the 25-minute concerto.