PASADENA, Calif. -- The celebrities on FOX's fall singing competition "Celebrity Duets" haven't been announced yet, but whoever they are, they'll have a fairly deep roster of recording artists backing them up.

A group of singers ranging from Motown legend Smokey Robinson to '80s pop stars Richard Marx and Cyndi Lauper will be taking part in the short-run show, which is being produced by "American Idol's" Simon Cowell. The 13 professional singers will be paired with other famous folks who aren't known for their vocal chops.

The lineup of celebrities hasn't been settled yet, but FOX chief Peter Ligouri assures that "as a public service," the show is making every effort to cast people who can actually carry a tune.

In addition to Robinson, Marx and Lauper, the other singers signed up for "Duets" are Macy Gray, Randy Travis, Dionne Warwick, Brian McKnight, Patti LaBelle, Chaka Khan, Aaron Neville, Clint Black, Kenny Loggins and Michael Bolton. Songwriter and producer David Foster, who was a guest coach on "American Idol" last season, will serve as a judge.

Each week, the celebs in the competition will be paired with a different singer and perform live with their partners. The audience will vote each week on which famous people go home, and the winner will earn a prize for his or her favorite charity.

"Celebrity Duets" premieres Tuesday, Aug. 29 and will move to its regular Thursday timeslot on Sept. 7. A results show will debut on Friday, Sept. 8.