T-Pain on Head-butting Taylor Swift, Calling out FKA Twigs and Going Without Auto-Tune

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T-Pain is making waves with his beautiful, non-auto-tuned rendition of the National Anthem, and only ETonline sat down with the star backstage before the big moment at Dodger Stadium on Monday.

WATCH: T-Pain Sings His Hits Without Auto-Tune and It's Awesome

"I don't use any kind of force manipulation or pitch correction in my performances, so it's always just me," says T-Pain, whose acoustic performances have gone viral in recent months. "I sound so much like my records that people just don't understand. People don't even know that some of my biggest records don't have auto-tune. Like 'Get Low' with Flo Rida."

T-Pain is hard at work on his forthcoming album, unveiling the first single, "Make It Work" featuring Juicy J, in June. The single may be a classic T-Pain auto-tune jam, but he says to expect plenty more of his natural voice on the full length.

"I always make sure there's natural voice on all my albums. There will be a lot more on this album because I'm just getting away from the whole auto-tune thing and it's not a big deal to me. I can go with or without it," he said. "I don't want to be sounding like everyone in the industry now."

T-Pain served as an innovator in the auto-tune trend, exploding on to the scene in 2005 with his breakout hit, "I'm Sprung." He's collaborated with Kanye West ("Good Life"), Akon ("Bartender"), Chris Brown ("Kiss Kiss"), Lil Wayne ("Can't Believe It"), and he famously appeared with Taylor Swift in a parody video for the 2009 CMT Music Awards titled "Thug Story."

READ: How Taylor Swift Turned Me From a Critic to a Swifty

"She wrote all that," he reveals. "I didn't help, at all. She wrote my parts, too."

"T-Swizzle" was an instant phenomenon, but surprisingly -- amid a laundry list of guest performers -- we haven't yet seen the pair reunite on Swift's 1989 Tour.

"A lot of her fans are tweeting [about that]," T-Pain says. "Keep the tweets coming!"

The 29-year-old superstar says Swift was "a jumper" and "very energetic" in the studio, but their collaboration did get off to a rocky start.

"She's so tall, that she was standing in the doorway of the studio and when I walked in, I thought there was a step up and I didn't look down," he recalls. "She was just that tall! And I did that little phantom step that you do, and I fell right into her. I, like, head-butted her right in the chest. It was weird. We worked it out -- she played it off like nothing happened, but I definitely head-butted her in the chest and that was very embarrassing."

But that's nothing compared to his big Oops! of 2015 -- unintentionally revealing that his pal FKA Twigs and Robert Pattinsonhad gotten engaged in an interview. He said, at the time, that it was an April Fool's Day prank.

NEWS: Did T-Pain Just Reveal That Robert Pattinson and FKA Twigs Are Engaged?

Asked point blank whether the remark was, in fact, intended as a joke, T-Pain reveals: "It was, until it turned real... I was actually just playin' [and] she was, like, 'That's a real thing.'"

T-Pain laughs off the misstep. "She wasn't mad because she hadn't told me," he says. "I joke about it all the time, but that one time it got heavy coverage."

He calls Twigs "one of my favorite artists," but kept tight-lipped on who might feature on his new album.

"I can't tease them yet [but] there are a lot more," he says. "Sometimes when I'm in my creative process, I'll get a feature and somewhere along the lines I'll say, 'Nevermind' and take it off, so I don't want to say that somebody's on the album and they don't make it... I got the verses and features, but some people just may not make it to the last process."

In the meantime, you can check out his latest (NSFW) single in the video below.

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