Question: The American Opera Society (AOS) was a which city based musical organization, that presented concert and semi-staged performances of operas between 1951 and 1970, the AOS also presented many operas to the American public for the first time, including the United States premieres of "Billy Budd", by Edward Benjamin Britten, an English composer, conductor and pianist, and a central figure of 20th-century British classical music?
Sentence (from "Berliner Operngruppe"): Since 2013 the semi-staged performances take place in Konzerthaus Berlin am Gendarmenmarkt.
Relevant evidence: No