1960, Britten revised the score into a two-act version, in preparation for a BBC broadcast. Vere's first appearance after the prologue had been originally the Captain's Muster, in which he addresses the crew at the end of Act 1; Britten cut this, explaining to his librettist Eric Crozier that he had never been happy with that scene, so making Vere's first appearance on the ship a private moment alone in his cabin. Britten changed some of the structural balance from the contrasting Acts 3 and 4. The first performance of the revised two-act version was on 9 January 1964 at the Royal Opera House, Covent Garden, conducted by Georg Solti. The 1966 BBC Television broadcast was conducted by Charles Mackerras, with Peter Glossop (baritone) as Billy, Peter Pears as Vere, and Michael Langdon as Claggart. The 1967 Decca studio recording was made of the two-act version; the recording sessions were attended by staff from the Royal Opera House, Covent Garden. The first USA performance of the revised two-act edition was on 4 January 1966 by the American Opera Society. The opera was produced in November 1970 at the Lyric Opera of Chicago, with Uppman reprising the title role, Richard Lewis as Vere, Geraint Evans as Claggart, Bruce Yarnell as Redburn, Raymond Michalski as Flint, and Arnold Voketaitis as Ratcliffe. The Metropolitan Opera first staged Billy Budd in 1978. Glyndebourne Festival Opera first staged the opera in 2010, in the operatic directorial debut of Michael Grandage; the production was revived in 2013. A new performing edition of the work, with a revised orchestration by Steuart Bedford, premiered at Des Moines Metro Opera on 1 July 2017. Baritones who have sung the role of Billy Budd include Sir Thomas Allen, Sir Simon Keenlyside, Richard Stilwell, Dale Duesing, Nathan Gunn, Rod Gilfry, Bo Skovhus, Thomas Hampson, Teddy Tahu Rhodes, Peter Mattei, Jacques Imbrailo and Liam Bonner. Notable Veres have included Peter Pears, Richard Cassilly, Philip Langridge, Anthony Rolfe Johnson, and John Mark Ainsley. Several academic studies investigate various thematic undertones in the opera, including homosexuality and salvation. Roles Billy Budd is one of very few operas to have an all-male cast. Instrumentation 4 flutes (2nd, 3rd and 4th doubling piccolos), 2 oboes, cor anglais, 2 clarinets (2nd doubling E-flat clarinet and 2nd bass clarinet), bass clarinet (doubling 3rd clarinet), alto saxophone, 2 bassoons, double bassoon, 4 horns, 4 trumpets (3rd in D), 3