2001: A Space Odyssey United States Library of Congress and selected for preservation in the National Film Registry. A musical score was commissioned for the film and composed by Alex North, but Kubrick ultimately decided not to use it, in favour of the classical pieces he used as guides during shooting. These included Richard Strauss's "Also Sprach Zarathustra", Johann Strauss' "Blue Danube Waltz", and music by twentieth-century composers Aram Khachaturian and Gyorgy Ligeti. Toward the end of the sequence where the HAL 9000 computer is lobotomized, it begins to play the 1892 song "Daisy Bell (Bicycle Built for Two)" by Harry Dacre, which Clarke
2001: A Space Odyssey (score) music would have been an improvement on the background music that Kubrick finally chose for the film." Conversely, in his notes for the Jerry Goldsmith recording, Kevin Mulhall argued that "there is no doubt that "2001" would have been better if Kubrick had used North's music. Even if one likes some of the choices Kubrick made for certain individual scenes, the eclectic group of classical composers employed by the director... resulted in a disturbing melange of sounds and styles overall." Film critic Roger Ebert noted that North's rejected score contains emotional cues to the viewer while the final music selections