Hannah Montana and Miley Cyrus, one and sort of the same, appeared at the Wachovia Center Monday night before an audience of several thousand healthy-lunged girls.

Hannah, the basis of the hit show on the Disney Channel, is a rock star by night. She's the one in the blond wig. Miley, her daytime persona, is the normal teenage girl - though you wouldn't know it from her Cher Jr. hard-rock ensemble and auburn hair extensions.

Being there and seeing her in that atmosphere, everything about it, and all the special effects made up for the fact that her singing isn't really great.

Well, yes, about that. The 15-year-old performer, daughter of country singer Billy Ray Cyrus who also plays her television father, is long on charm but undistinguished as a vocalist. She doesn't sing. She wrestles songs to the stage.

The noise level? Hive-inducing. Several parents, sacrificing sanity and hearing, were helping themselves to a Mommy beer.

Miley's performance, heavy on strutting and hollering, resembles cheerleading more than pop music. This was her 40th concert on a punishing tour schedule. Her exhaustion was visible, especially for a show scripted to the second, displayed on multiple JumboTrons and utterly devoid of spontaneity. Why was she constantly hugging her dancers? Doesn't she socialize with them backstage?

I was worried about her. She made me hot just looking at her.

And because she performed only one slow song, her encore "I Miss You," in bare feet on a stool, the show was at Red Bull level right out of the gate. If you're going to run around that much, preening constantly down the runway-like stage, the singing is going to take a serious hit.

I liked "Life's What You Make It" and "Nobody's Perfect." They both had good, strong messages.

The Jonas Brothers - Joe, Kevin and Nick - opened for Hannah/Miley to much screaming and returned later to accompany her. Kevin and Nick, 20 and 15 respectively, play guitar. Joe, 18, preens.

He has the best hair and the loudest fans, though it was disconcerting to hear a 6-year-old scream "I love you, Joe." If memory serves, we were never this frenzied about Mick and Keith.

Miley and Nick are so going out together.

For the record, the souvenir program was $20. The Pepto-Bismol pink hoodie, $60. Hannah/Miley sang 18 songs and wore seven costumes, which favored fuchsia and sequins. The Jonas brothers also wore sequins. Someone in wardrobe is jonesing for sequined ties, a rueful sartorial statement the first time they surfaced in the '80s.

The evening's greatest curiosity was how to keep the Disney in a concert listing toward rock when the two are antithetical. How do you remove the sizzle from contemporary music and herd a 15-year-old from going full Britney? One way is to dress the star, dancers and singers in cartoon costumes, sneakers and sensible boots, though some of Miley's moves veered dangerously toward sultry.

My favorite outfit was the black dress with the purple skirt and black sneakers. The pink party dress was so last year. They kept things exciting with fireworks and streamers, and made the show fast and loud so it was more about the excitement.

Absolutely. There wasn't an unhappy girl in the place.

Contact staff writer Karen Heller at 215-854-2586 or kheller@phillynews.com. Cece Dye, 11, is Karen's daughter.