タングルウッド音楽祭
In 1972 Ahlstedt made his debut at the San Francisco Opera as Koby in the United States premiere of Gottfried von Einem's "Der Besuch der alten Dame". That same year he made his debut at the Tanglewood Music Festival as the Boy in Ian Strasfogel's "The Yes Men", and was also heard at Tanglewood that year as Soldato pretoriano in "L'incoronazione di Poppea".