The Cleveland Orchestra is back at Severance Hall for the season. And the first sounds that ticket holders will hear are those of Beethoven. French-born, Swiss-based pianist Hélène Grimaud will be the soloist when Metropolitan Opera principal conductor Fabio Luisi leads the orchestra in the Emperor Concerto. There's Mahler too! His Symphony No. 5 is on the bill Thursday and Saturday, while the Friday evening audience is treated to Schumann's Symphony No. 1. Thu 9/19-Sat 9/21.