iHeartRadio Music Festival, Clear Channel's two-night pop extravaganza, got off to a rousing start on Friday night (Sept. 23) with performances by Jay-Z, Coldplay, Alicia Keys and Bruno Mars, among others. The red carpet at the MGM Grand in Las Vegas remained just as busy, with artists like Jane's Addiction, Joe Jonas and Karmin stopping by to chat about their new projects as well as the jam-packed event that brought them to the desert.

PHOTOS: iHeartRadio Music Festival

"I would love to see Coldplay, I would love to see Jay-Z... [Bruno Mars] sounds great live. There's just a bunch of people!" says Nick Noonan of viral video stars Karmin, who performed a cover of Nicki Minaj's "Super Bass" halfway through the show.  As Ryan Seacrest, who helped introduce artists like Jay-Z and Kelly Clarkson throughout the night, puts it, "To put all these artists together sort of typifies what iHeartRadio's all about."

Check out more red carpet video, including Jane's Addiction talking about their forthcoming album "The Great Escape Artist," Joe Jonas getting pumped for his European tour with Britney Spears, and Karmin dishing on their debut album. Click here for a full recap of last night's show, including video of every iHeartRadio Fest performance.

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