Pittsburgh Opera presents Gregory Spears' "Fellow Travelers" for 3 performances only - Friday November 14th (7pm), Saturday November 15th (7pm), and Sunday November 16th (2pm) at the Byham Theater. WQED-FM's Anna Singer spoke with Pittsburgh Opera Music Director Antony Walker, who talks about the music, the historical context of the opera, and how he thinks its important as a conductor to sit in on every voice rehearsal.