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For example, why did Beethoven choose C sharp minor when composing his moonlight sonata while choosing f minor for appassionata? Why did he not choose to compose all of his works in C major or A minor, which are the easiest ones?

marked as duplicate by Dom, Micah, Karen, guidot, Kevin Sep 18 '14 at 17:30

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  • I guess he just listened to his composition and played in in which key sounded the most beautiful. Also maybe which is most easy to play? – Valentin Grégoire Sep 18 '14 at 15:14
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    What makes you think that Cmaj and Amin are the 'easiest' keys? On several instruments they are NOT the easiest. – Tim Sep 18 '14 at 16:55
  • Try putting a midi file through some music software that 'transposes' it so you can hear the same piece in different keys. You should notice subtle (and possibly not so subtle) differences in the feel of the piece... Part of the composers task is to know which will produce the best result... As for the C and Am there only easier for the piano player, makes barely any difference to the composer. – norlesh Sep 19 '14 at 0:14

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