For Mayer, too much restraint

John Mayer the pop heartthrob and John Mayer the rigorous instrumentalist shared the stage in Boston Tuesday, and while the artist's key attributes aren't exactly in conflict, they're not in perfect harmony, either. What seems to be missing is nerve.

During a solid but uninspired set, Mayer's riffs were crisp, the solos searing, and his range was genuinely impressive: The intro to "Vultures" sounded for all the world like a strummed cowbell (muted and ringing all at once), and a short, slash-and-burn finale gave the breezy confection "Bigger Than My Body" unexpected heft. But the mellow troubadour was reticent to let the guitar god cut loose. Mayer's buffed, poised solos sounded more like the work of a well-practiced protege than a deep, passionate player, and there's nothing more frustrating than a musician who's long on chops and short on spirit.

Maybe it was all those fresh-faced girls with cell phones in the air hankering for the night's next singalong. Mayer's got a fan base to attend to, and he serviced the sold-out, estrogen-heavy audience with the winsome anthems "Why Georgia" and "No Such Thing" -- the latter written, the former Berklee student announced, "at 150 Mass. Ave." Mayer looked and sounded like an adorable puppy. He must have killed in the dorm stairwell.

But at 29, Mayer is also trying to distance himself from his sweeter, slighter side. He neglected two of his biggest hits, "Daughters" and "Your Body is a Wonderland," opting instead to focus on some of the more soulful cuts from his recent disc, "Continuum." Backed by a seven-piece band, Mayer opened the concert with "Waiting on the World to Change," an anti war anthem indebted to Curtis Mayfield's "People Get Ready." He evoked the classic-rock balladry of the Eagles on "Dreaming With a Broken Heart" and the jazzy cool of Steely Dan during "Belief."

"Gravity," a poignant blues-waltz that closed Mayer's main set, was given the scorching guitar coda the song begs for on disc, only to be followed by a chronological medley of Mayer's earliest songwriting efforts that wasn't, to put it mildly, encore-worthy. Mayer is straddling worlds -- he's a laid-back tunesmith and burgeoning soul man, a mop-topped pin up and an ambitious musician -- and he can't quite lose himself in any of them. If and when he figures out how to embrace his full array of gifts, Mayer will be a formidable pop star.

Opener Ben Folds rose above a seriously awful sound mix with an hour-long, career-spanning set of pummeling pop-rock that included Ben Folds Five gems "Kate," "Narcolepsy," and "One Angry Dwarf and 200 Solemn Faces," as well as the topical solo tunes "Army," "All U Can Eat," and "Jesusland."

Joan Anderman can be reached at anderman@globe.com. For more on music visit boston.com/ae/ music/blog.