Britney Spears sings live! According to Piece Of Me Director

"Britney sings every song live, but there are additional tracks when they're doing the heavy dance numbers. Snapshots give Marc the security of knowing that these levels that they work on so hard translate to the live environment."

"Britney pretty much has to stick to her script, but I have a lot of freedom to play different chords or different sounds," continues Delcore. "Anything that the band throws at him, Cubby hears right away and he makes the adjustment. He catches everything and is able to make those adjustments with the console. It's important for him to be able to make those changes on the fly. He's such a great engineer."

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