The Ambrosian Opera Chorus is the soubriquet under which the Ambrosian Singers, founded in 1956, have made innumerable recordings of operas and American musicals. The group's precursor was established by musicologist/author Denis Stevens and tenor John McCarthy for the performance of stylistically correct examples of early music. As Stevens had become a part of the BBC's music department in 1949, he was assigned oversight for the company's series, The History of Western Music, the chorus' first major project. After Stevens' departure for the United States in 1955, the chorus reconstituted itself as the Ambrosian Consort and later, the Ambrosian Singers. As a center of classical recording activity since the 1920s, London grew steadily as a sight for recorded opera, and the choral singers available to the Ambrosians expanded into the hundreds. Thus, a producer for any of the major record labels could count on having a chorus of any size necessary, one composed of professional singers who sight-read accurately and who could learn music quickly. In fact, the chorus appeared under a variety of names, including the John McCarthy Singers and, during McCarthy's tenure as choral director of the London Symphony Orchestra from 1961 to 1966, the London Symphony Orchestra Chorus. In its opera guise, the Ambrosians have recorded for EMI, London/Decca, Philips, RCA, and Sony, among others. For EMI, notable projects have included Boito's Mefistofele, Delius' A Village Romeo & Juliet, Vaughan Williams' Riders to the Sea, Ambroise Thomas' Hamlet, and Verdi's Don Carlo, Macbeth, and La forza del destino. For London/Decca, several of Joan Sutherland's most celebrated recordings featured the Ambrosian Opera Chorus, notably Semiramide, Les Huguenots, and Rigoletto. Philips engaged the chorus for its Il barbière di Siviglia with Thomas Allan and I Masnadieri and Il Corsaro with Montserrat Caballé. For RCA, Leontyne Price's second Il Trovatore employed the chorus as did a recording of Montemezzi's L'amore dei tre re with Anna Moffo and Cesare Siepi. Among Sony projects were Thomas' Mignon with Marilyn Horne and Charpentier's Louis featuring Ileana Cotrubas in the title role. Opera recitals by such singers as Leontyne Price, Alfredo Kraus, Caballé, and Jessye Norman have also included the Ambrosians. In addition to opera, the Ambrosian Opera Chorus has recorded such musicals as Showboat, Babes in Toyland, Kismet, and The Student Prince.