This month Daniel Barenboim leads the Staatskapelle Berlin in three European performances, beginning September 4 at Cologne’s Philharmonie with a program of Schubert’s Symphony No. 8, “Unfinished,” and Strauss’s Ein Heldenleben. The following evening on September 5, Barenboim and the Staatskapelle reprise their performance of Schubert and Strauss at the Rheingau Musik Festival. The September performances abroad conclude September 7 at Finlandia Hall as part of the Helsinki Festival.