Taylor Swift experiments with EDM and dubstep on 'I Knew You Were Trouble.,' one of the promotional singles from 'Red.' But if you asked her before it came out what it sounded like, she wouldn't really have been able to tell you.

"What ended up happening was, I wrote this melody for this chorus on the piano [for 'I Knew You Were Trouble'], and I brought it to [producers] Max Martin and Shellback, and I said, 'At the end of the chorus, I just want this to go crazy,'" she told Spin (via MTV News). "'I want it to be really chaotic.'"

She had a hard time describing the sound to her producers, but went along with it once they said what it was. "I don't really know what to call it, but I just kind of sing it how I want it to sound. And they're like, 'Oh, sort of like a dubstep thing.' And I'm like, 'I guess, I don't know? Whatever that is, whatever that ridiculous sound that I made with my mouth when I was trying to figure out what to say,' " she said. "You end up doing a lot of that when you're recording and writing, being like, 'It kinda sounds like this!' I wanted the song to sound as chaotic as the emotion felt. I wanted it to be loud and out of control."

Swift revealed that she first discovered dubstep sounds from Ed Sheeran, her partner on 'Everything Has Changed.' "I've written some with Ed Sheeran, and he's become a good friend of mine, and he always plays me really interesting stuff from the U.K. whenever he comes over and hangs out," she said. "But I never really thought, 'Hey, I want to download some dubstep music!'"

Maybe her next collaboration will be with Skrillex. Hey, we can dream!

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