Jennifer Lopez, Steven Tyler to Headline iHeartRadio Music Festival

Jennifer Lopez, Steven Tyler - Fox's "American Idol 2011" Finale - 2011
Kevin Winter/Getty Images

The Season 10 "Idol" judges join Lady Gaga for the Ryan Seacrest hosted concert, to take place Sept. in Vegas.

Ryan Seacrest and Jennifer Lopez had a big announcement today, and surprisingly, it wasn’t about American Idol.

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Clear Channel radio will hold the first ever iHeartRadio Music Festival at the MGM Grand in Las Vegas on September 23 and 24. Hosted by Seacrest, the two-day festival is set to break records as the biggest live concert festival in radio history.

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“This is a once in a generation gathering of artists and fans from all over the country for a true, must-see music event,” said Seacrest. “The iHeartRadio Music Festival, like the iHeartRadio digital radio service, will showcase top artists across all genres of music. Listeners from all over America will travel to Las Vegas to celebrate the next generation of iHeart Radio, while seeing the greatest musicians in the world on one stage.”

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Artists taking the stage include Lady Gaga, Coldplay, The Black Eyed Peas, Kenny Chesney, Nicki Minaj, John Mayer and more. There will also be a few Idols in the house, with Kelly Clarkson and Carrie Underwood slated to perform as well as judges Steven Tyler and Jennifer Lopez, who still remains mum on whether she’ll sign for another season.
Tickets are available for pre-sale via the iHeartRadio Facebook page and will go on sale to the general public on July 16 at 1:00 p.m. ET at with the keyword “Vegas.”

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Find a complete list of performers below. According to Seacrest’s website, more acts will be announced all summer long.
Lady Gaga
Alicia Keys
Steven Tyler
The Black Eyed Peas
Kenny Chesney
Jennifer Lopez
Carrie Underwood
Jane’s Addiction
Nicki Minaj
John Mayer
David Guetta
Rascal Flatts
Bruno Mars
Kelly Clarkson
Sublime with Rome
Special performances from Usher and Sting