‘Boy’ grows up -- if his fans will let him

“Ladies and gentlemen, this ain’t no boy band,” the announcer exclaimed as A.J. McLean of the Backstreet Boys rolled onto the stage Monday at the Roxy. It certainly wasn’t. McLean generated boy-band-worthy shrieks from female fans but created a rock ‘n’ roll mood, sporting black nail polish and eyeliner, and celebrating the night’s lack of PG-propriety by cursing and being sexually provocative. But given a 90-minute set that was all over the place stylistically, he is still figuring out who he is on his own.

The performance, which showcased material from his solo debut due later this year, was only his second solo date. His band, which included four members of the Backstreet Boys’ touring band as well as a three-piece horn section and two backup singers, sounded under-rehearsed. But McLean displayed winning enthusiasm and a humility remarkable for someone who has sold millions of albums and charted numerous times with his other group, which is about to embark on a European tour. He introduced each song by explaining his inspiration and giving ample credit to his co-songwriters, including sometime Backstreet Boys producer Kristian Lundin.

The set ranged from the kinetic, horn-laden sound of “Love Me Crazy” to the electro-rock vibe of “Have It All” and the earnest ballad “I Hate It When You’re Gone.” McLean’s vocals were strong, but he sounded more like a performer than a singer expressing his own voice and personality.

If McLean is experiencing growing pains, it’s also unclear whether fans will let him mature. Many on hand were almost more interested in seeing him strip than sing. They went crazy for any Backstreet Boys mention, including a moody, rock version of the group’s “Incomplete.” When he sat to play acoustic guitar on the blues pop ballad “Life Is Just,” fans chatted loudly.

Several pop numbers were good fun, especially when he delivered a Prince-worthy falsetto during “Gorgeous,” which could be summer’s guilty pop pleasure. McLean finally bared real emotion and pushed his vocals during an intense power ballad, “Sincerely Yours,” about his painful relationship with his absent father. McLean clearly has personality to spare and a devoted fan base. Now he needs to find his solo music persona or a way to just be himself in his songs.