BOSTON -- When you're talking about Mariah Carey, it all starts with the voice. Or, as she billed it herself on the tour that rolled into the TD Banknorth Garden last night, The Voice.

It was in good shape last night, but it's one thing to have such a force of nature; it's another to know what to do with it. And I'm not talking about the oversinging she's so often accused of; that's her deal, and if you can't get used to that, well, this deep into her career you've given it a fair shot. (It only grated on the encore, "We Belong Together.") She's still head-and-shoulders above the generation of American Idol doofuses trying to follow in her footsteps.

But on the hip-hop-influenced material that's come to dominate her recorded output, such as the set opener "It's Like That," "Heartbreaker" (with video rap cameo from Jay-Z) and "Fantasy" (with video rap cameo from Ol' Dirty Bastard), she fell victim to the Van Halen syndrome -- imitating one's imitators and undermining one's own strengths -- sounding like any one of a number of thin-voiced contemporary R&B divas, with a couple of the trademark Carey helium notes thrown in so you know whom you're dealing with, but to not much other discernible effect.

The Voice was used to better effect on opulent R&B such as the old hit "Dreamlover" and "Fly Like a Bird" and "I Wish You Knew" (from last year's The Emancipation of Mimi album), when she wasn't singing like she had something to prove, which unfortunately isn't nearly as often as you'd think it would be at this stage of her career. This is the stuff very few singers Carey's age or younger are doing, because very few can handle it. But there wasn't enough last night, and too many forgettable recent hits.

The pacing of the show was a bit of a mess. The middle of the set was loaded with filler, including a DJ spotlight and a three-song set from "I'll Be There" vocal partner Trey Lorenz. The end of the show was bogged down with another DJ spotlight, snippets of songs such as "I Wish You Knew" and forced banter from Carey before finishing up with "Hero" and "Make It Happen."

When The Emancipation of Mimi came out last year, more than a few people wondered exactly what it was she claimed to be emancipated from. Similarly, the introductory video to last night's concert featured footage of a roller coaster with a voiceover from Carey about how life was like, well, a roller coaster. Ups and downs, hold on, that sort of thing.

That was pretty much it for the philosophizing, and while that may have been just as well, most of the material seemed to come from a mindset most commonly expressed in the margins of a notebook during third-period algebra: Look inside you and be strong. I'm gonna shake you off. Baby, don't forget about us. Make it happen.

Which is a shame. At this point, with her raw talent, Carey should be leading, not following. Sure, Emancipation was last year's top seller. But last night's show didn't leave the impression of a young singer baring her soul or an older singer baring her scars. Or much of anything. Except The Voice.

Opener Sean Paul was a rousing force, using a DJ, a backing band and synthesized beats to re-create some of his biggest hits, particularly from his latest album, The Trinity. The live band gave new life to such dancehall hits as "We Be Burnin'" and "Get It On."

rmassimo@projo.com / (401) 277-7206