LaBelle Lets Hair Down, Can’t Unleash Passion : In Celebrity Theatre show, her voice seems rarely motivated by feelings or lyrical content, relying instead on histrionics and bombast.

There’s something a bit unsettling about Patti LaBelle hawking Big Macs on the tube. Folks are worried enough about hair in their food without having to contend with the notion of LaBelle’s spiky hairdos shedding (“Excuse me, waiter, but I believe there’s a porcupine quill in my cheeseburger”).

But, while the wares she’s advertising in the commercials are at least all beef, there seemed to be more than a little bull to the R & B diva’s early show at the Celebrity Theatre Friday evening.

The 47-year-old singer may be one of the nicest people in the world--it would certainly seem so by the charitable organizations she aids and the number of friends she has in the music biz. And there’s no question she has one of the most formidable voices in popular music, with an operatic range and power, and no reluctance to send it into dizzying swoops or a maze of melodic twists.

But LaBelle’s voice seems only rarely to be motivated by emotion or lyrical content, far more often relying on histrionics and bombast to carry a song. She delivers all the fuel and flash of the great gospel-based soul singers, but not the genuine heat and fire.

While her hair was none too extreme Friday--looking like a ‘60s Darlene Love ‘do rather than the trademark LaBelle fan-like styles that seem designed to hold a taco salad--her voice was on full-tilt.

In many cases she paid only cursory attention to a song’s lyrics and melody before the excess kicked in. Hence, her version of the classic “If You Don’t Know Me by Now” goes something like this: “All the things that we’ve been through/You should understand me like I Screeeeeeeeeeee !! Eiiiiiiieeeeeeee ! Yowllll . . . “ and so on until the lunch bell rings. Combined with a sound system that boosted her upper-register efforts beyond distortion, the net effect was a bit like having your head shot at with a nail gun for an hour and a half.

Which isn’t to say there weren’t some fine moments in there somewhere. Even if not connecting emotionally, some of the flights her voice took were breathtaking, particularly on her shouted encore rendition of “Over the Rainbow.”

There were instances, too, when her overwhelming show of technique spilled into an emotional outburst, as she did with a cascading series of high-pitched screams and shouts on “The Wind Beneath My Wings.” But even at her best there, it paled beside what New Orleans great Irma Thomas does with the song in her concerts.

For LaBelle’s fans, though--and there are enough locally to warrant two Celebrity shows--she can do no wrong. In return LaBelle seems to have a genuine affection for her crowds, bantering with audience members, dancing with some and graciously accepting their cavalcade of gifts--which included a pair of ruby slippers given to her by a fellow in a blue-sequined top. She also collected donations, which she said are given to local charities after the shows.

Reaching back to her days fronting the group LaBelle, she sort-of performed “Lady Marmalade,” though between dancing with men from the audience and screaming she managed to avoid actually singing any of the lyrics. There also was her old hit “New Attitude,” a barely recognizable version of “Send in the Clowns,” covers of Aretha Franklin’s “Ain’t No Way” and other recent hits and songs from her current “Burnin’ ” album, all sung with the subtlety of a police siren. The “Burnin’ ” songs included “Somebody Loves You Baby (You Know Who It Is),” “Feels Like Another One” with a guest rap from Big Daddy Kane, and “When You’ve Been Blessed (Feels Like Heaven)” performed with a 17-voice choir joining her backup singers and pit band.