New York ? The first time Liz Phair pooled her allowance money to buy a record, years before she became an indie rock queen, she bought “Saturday Night” by the bubble-gum band Bay City Rollers.

That’s worth remembering now that the 36-year-old singer has set off an extraordinary debate in the rock world simply by making a disc designed to be enjoyed by as many people as possible.

Some fans feel betrayed, others intrigued. All can judge for themselves when the disc, her first in five years, is released today.

Titled “Liz Phair,” the cover features the star with teased blonde hair and a semi-dressed pose covered up by a strategically placed guitar. Among the 14 glossy pop-rock songs are four co-written with the Matrix, the hitmaking songwriting team behind Avril Lavigne’s smash, “Complicated.”

Her debut a decade ago, on the other hand, was decidedly lo-fi. Complete with frank sexual talk, “Exile in Guyville” was a brash, feminine response to a classic Rolling Stones album. Critics and hipsters loved it, saying it captured the mood of many women in their 20s.

Will the real Liz Phair please stand up?

“I’m the same person I always was,” Phair said recently. “I just lost the whole ‘cool school’ thing.”

By courting pop success, some critics have essentially called her a sellout. In a lengthy essay Sunday in The New York Times, writer Meghan O’Rourke said Phair “has committed an embarrassing form of career suicide.”

Phair recorded and shelved three albums in the past five years, as she got divorced and moved with her 6-year-old son from her native Chicago area to Los Angeles.

As a single mom living in an expensive new area, Phair was eager to take a big swing at success and agreed to work with the Matrix. “Exile in Guyville” and its 1994 follow-up, “Whip Smart,” both sold just under 400,000 copies, and 1998’s “whitechocolatespaceegg” sold 266,000 copies — respectable if you’re a struggling artist-type, but not on the level of a major star.

Phair believes working with others has amplified, not concealed, her personality. She said she wasn’t turning her back on the woman who wrote “Exile in Guyville.”

“What did you do in your 20s?” she said. “Oh, I wrote one of the most influential albums of the ’90s. It’s awesome. But it shouldn’t stop you” from trying different things, she said.