Early performances in his career included George Frideric Handel's Utrecht Te Deum and Jubilate with the City of Birmingham Symphony Orchestra.
He returned to The Proms as soloist over the next 12 years, singing in performances of Giuseppe Verdi's Aida (1954), Richard Wagner's Die Walküre (1955), Samuel Coleridge-Taylor's The Song of Hiawatha (1956), Wagner's The Flying Dutchman (1957), Maurice Johnstone's [Wikidata] Dover Beach (1958), Ralph Vaughan Williams' A Sea Symphony (1959), and Hector Berlioz's La damnation de Faust (1962).
[6] On 1 December 1951 Alan created the role of Mr. Redburn in the world premiere of Benjamin Britten's landmark work Billy Budd at the Royal Opera House, London.
[7] From 1952 until 1963 he performed frequently with the Welsh National Opera, including the roles of Federico Barbarossa in La battaglia di Legnano, Melchtal in William Tell, Méphistophélès in Faust, Procida in I vespri siciliani, Sparafucile in Rigoletto, and a much lauded portrayal of Zaccaria in Verdi's Nabucco.
[2] He also taught on the voice faculty at the Royal College of Music where his pupils included soprano Janet Price and baritone Thomas Allen.