(Rolling Stone) -- "I went through a few roller coasters," says Taylor Swift, reflecting on her relationships over the past two years. She channeled the turmoil into her fourth studio LP, "Red," out October 22. "Trying to chronicle each step of the way was challenging, because you go to some really dark places with the lyrics. Then in the next track, you're talking about how amazing it is to meet somebody new."
After writing 2010's smash "Speak Now" by herself, Swift veered in the opposite direction, co-writing with pop hitmakers such as Max Martin and Adele collaborator Dan Wilson. She wound up with nearly 40 potential songs; in between stops on the yearlong world tour that she wrapped in March, Swift joined her writing partners in L.A. and Nashville. "I felt like an apprentice," Swift says. "They taught me so much about melodic sense, and they let me do what I love, which is the lyrics."
The result is Swift's most eclectic set ever, ranging from "State of Grace," a howling, U2-style epic with reverb-drenched guitars, to a sweet acoustic duet with U.K. singer Ed Sheeran. Another key track even features a dubstep-inspired bass breakdown. So far, the new direction isn't hurting Swift's career: Lead single "We Are Never Ever Getting Back Together," a bitter breakup anthem with a hip-hop-flavored Max Martin beat, has shattered chart records, selling a stunning 623,000 digital singles in its first week.
To Swift, the musical excursions aren't surprising, given how much hip-hop and R&B she listens to. "I have so many play-lists full of Rihanna, Nicki Minaj, Lil Wayne, Chris Brown," she says. "I love Wiz Khalifa."
Lyrically, the album is full of Swift's usual themes of romance and heartbreak. "I know general things about love," she says. "How to treat people well, what you deserve and when to walk away. Other than that, love is a complete mystery -- and that's why I like to write about it."
Swift has spent much of the summer with her new boyfriend, Conor Kennedy (the son of Robert F. Kennedy Jr.), in Hyannis Port, Massachusetts. She's even looked into buying a house near the Kennedy compound. "That would be so amazing," she says. But Swift won't be resting for long: She's already thinking about how to top her last tour, which featured aerialists, costume changes and a mock wedding onstage every night.
"I really want to go out on the road in the spring," she says. "After I write a song, I always end up laying awake at night thinking, 'What are the lighting cues going to be on this? How big is the pit going to be?' I have been thinking of some big moments that are going to happen."
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