The music is a thematic extension of Alex's (and the viewer's) psychological conditioning. The soundtrack of A Clockwork Orange comprises classical music and electronic synthetic music composed by Wendy Carlos (who, having not yet undergone sex reassignment surgery, was credited as "Walter Carlos"). Some of the music is heard only as excerpts, e.g. Edward Elgar's Pomp and Circumstance March No. 1 (aka Land of Hope and Glory) ironically heralding a politician's appearance at the prison. The main theme is an electronic transcription of Henry Purcell's Music for the Funeral of Queen Mary, composed in 1695, for the procession of Queen Mary's cortège through London en route to Westminster Abbey. "March from A Clockwork Orange" was the first recorded song featuring a vocoder for the singing; synthpop bands often cite it as their inspiration. Neither the end-credits, nor the soundtrack album, name the orchestra playing the Ninth Symphony excerpts, however, in Alex's bedroom, there is a close-up of a microcassette tape labeled: Deutsche Grammophon – Ludwig van Beethoven – Symphonie Nr. 9 d-moll, op. 125 – Berliner Philharmoniker – Chor der St. Hedwigskathedrale – Ferenc Fricsay – Irmgard Seefried, Maureen Forrester, Dietrich Fischer-Dieskau, Ernst Haefliger. It was originally intended to use music entirely by Carlos. But the synthesized selections weren't finished on time, hence the final mix of synthesized and orchestral music.