Ashlee Simpson. “Bittersweet World” (Geffen Records)

So she can’t sing live. And she hasn’t got anything like a credible image. And the timing of her announced engagement to, and reported pregnancy by, Fall Out Boy’s Pete Wentz was a tad on the tacky side, arriving less than two weeks before her new album entered a chancy market.

There’s still no denying that Ashlee Simpson has found her cover-girl face - and cleverly manipulated voice - attached to some of the most youthful and pleasing teen pop of this decade.

Simpson’s debut CD, 2004’s “Autobiography,” had a kick, melodic flair and hook appeal rarely found in the dreary world of modern pimple-pop. The songs staked out Avril Lavigne’s faux-punkette territory, but greatly improved on her songcraft and production punch.

True, Simpson stumbled badly on CD No. 2 - 2005’s more “thoughtful” (read ponderous) “I Am Me.” She cut it in the wake of her post-”Saturday Night Live” lip-sync meltdown, accounting for its wounded tone, which hardly flattered her forte of pluckiness.

Now, for her third work, “Bittersweet World” (out today), Simpson has again found her brand name, and vocal timbre, plopped into a properly exuberant package.

She didn’t take any chances with the crew on board for her resurrection. Half the album comes courtesy of all-mighty producer Timbaland. The other half she turned over to the nearly as starry Chad Hugo (the nonsinging half of The Neptunes).

Despite the divided workload, the CD maintains a surprisingly uniform tone and style. “Bittersweet” doesn’t repeat the mall punk rock of “Autobiography” or the faux singer-songwriter style of “I Am Me.” Instead, Simpson decided to raid Gwen Stefani’s closet, rummaging through her retro ’80s L.A. new-wave duds for some technicolor inspiration.

That means we get lots of electro-squeaky hooks and danceable synth gurgles, each referring back to the era of Missing Persons and Berlin. Yet Simpson betters Stefani’s take on the era, axing the annoying chirps in the vocals and, again, finding better melodies than her role model ever has.

You won’t be able to get a song like “Outta My Head” outta yours. “Hot Stuff” shows the Neptunes’ flair for charging dance beats at their fluffiest. Here, and elsewhere, the pseudo-naughty lyrics are a camp scream. They may not present Simpson as a credible rebel, but they do allow her to act as a pleasing scamp.

With lures this sweet, it doesn’t matter what we think of the younger Simpson herself. She has become part of recordings that have a life of their own.