Reading and Leeds: How do bands choose entrance songs?
28 August 2013 Last updated at 06:10 BST
Three of the acts at this year's Reading and Leeds Festival have told Newsbeat how they decide which music they play to fans just before they walk on stage.
Chase and Status, Alt-J and Mallory Knox say it's an important way to make sure crowds are "warmed up" for their sets.
They were speaking to Newsbeat's music reporter Sinead Garvan, backstage at Leeds.
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