Pittsburgh Opera presents “Pagliacci” and “Cavalleria Rusticana” at the Benedum Center November 9th through the 17th. Sebastian Catana is the only singer who performs in both operas – Alfio in “Cavalleria Rusticana” and Tonio in “Pagliacci.” He spoke with WQED-FM’s Anna Singer about singing in both operas, how the characters are different and more.