Milli Vanilli Is Really a Marcel Marceau Act : Music: Another group recorded the vocals that the 1989 Grammy-winning duo simply lip-sync, their producer says.

The rumors are true: Milli Vanilli--those dreadlocked, hunky dudes Rob and Fab--never actually sang on their debut album that sold 7 million copies, the producer-arranger conceded.

“The record company never knew that. I never told them anything,” said Frank Farian, the German producer who turned a pair of anonymous pretty boys into an international phenomenon. “Later on, after the record was out, there were some people who raised some questions.”

The questions were never really answered as the Vanillis won a 1989 Grammy for Best New Artist. Rob Pilatus and Fab Morvan became international stars, lip-syncing their way through television and concert appearances.

“Girl You Know It’s True” and “Blame It on the Rain” were huge hit singles for the band. At the MTV awards, the boys boasted they were better than Elvis or Bob Dylan.

Farian--who has a new album with a new group coming out in January--said he was forced to go public with the revelations when the guys told him they wanted to sing on the follow-up to “Girl You Know It’s True.”

“I said, ‘No. I don’t go for that.’ Sure, they have a voice, but that’s not really what I want to use on my records,” said Farian, describing the encounter that occurred earlier this month.

So the bare-chested vocalists once described by the New York Times as “exotically sexy” really did nothing but look good and lip sync for videos?

“Nothing more,” Farian said through an interpreter during an interview here Wednesday.

A telephone message left today to the group’s manager in Germany was not immediately returned.

Farian’s revelation didn’t bother Arista, the label that sold “Girl You Know It’s True.”

“Seven million albums? Embarrassing?” asked Roy Lott, vice president for operations at Arista. “I don’t mean the end justifies the means. But we sold 7 million albums.”

Lott said there was no reason to doubt Farian’s veracity: “I certainly assume the producer would know who sang on the record.”

According to Farian, the idea to hire Rob and Fab as front men for the band came to him when the fabulous bunko boys arrived at his studio in Germany shortly after the recording of “Girl You Know It’s True.”

“It suddenly clicked in my mind, and it was kind of evident: I had the music, there were the people who wanted to perform outside,” Farian said. “And I said, “Hey, let’s put that together and make a great record out of it.’ ”

Farian would not say who the real singers were but added that they will appear on his next album--not a Milli Vanilli album.

Lott said the label is unconcerned about the dupe, and it plans to distribute Farian’s new album. Lott has heard some of the record already, and he said “Frank has my full support.”

As to Rob and Fab, well, their future’s a bit more uncertain.

“We are purely their distributor. We do not have a specific deal with Rob or Fab,” Lott said.