Not all carillons use a keyboard. Some of them are automated, meaning they play music without a human. They can be controlled using a clockwork mechanism, similar to the one in Big Ben, so that the music plays at certain times every day. Two examples of this kind of carillon are the Spasskaya Tower of the Moscow Kremlin and the Munttoren in Amsterdam. More recent carillons, such as the one in the Peace Tower in Ottawa, are computer-controlled.