Record producer Randy Jackson remains the only original judge since the program debuted on Fox television in 2001, and Ryan Seacrest will remain as host. Lopez and Tyler replace British judge Simon Cowell, talk show host Ellen DeGeneres and songwriter Kara DioGuardi.

Tyler said on Wednesday he wanted to "bring some rock to this rollercoaster".

"I want to give everybody a little love before I decide who goes home heartbroken. If you don't like what I say, don't get mad, get better," the colorful Aerosmith showman added.

Lopez, star of movies like "The Wedding Planner", said she had long been a fan of the show and that the opportunity to be a judge "felt like the right thing at the right time for me."

"American Idol" producers announced other big changes to get away from what they called the "karaoke" feel of the show when it returns to U.S. television in January 2011 after a four year ratings decline on viewer ship.  But financially, "American Idol" has generated huge advertising revenues for Fox over the years and boosted record sales and digital downloads for early winners like Clarkson and Carrie Underwood.

The tenth season of American Idol is slated to premiere on January 12, 2011 on Fox