WBMX-FM's slogan is "today's best variety," and the cavalcade of radio stars at Saturday's MixFest indeed spanned the reaches of the station's playlist. But diversity within a mainstream pop-rock format doesn't add up to a smorgasbord of sounds. The difference between Five for Fighting's pretty piano ballads, Maroon 5's buoyant pop tunes, and John Mayer's infectious love songs is a matter of minute degrees. Take away Mayer's guitar chops, Maroon 5's soulful disposition, and John Ondrasik's serious self-involvement, and you're left with several hours of pleasant melodies. Alanis Morissette, the only female on the bill, could have beaten all three up without missing a single syllable of her righteously verbose set. Additionally, she can sing about scumbags and smile beatifically at the same time, which inspired a loud chorus of women in the near-capacity audience to join in on lead vocals. The fact that Morissette was the only performer of the many plagued by sound problems to simply beam and forge ahead may or may not be gender-related; Ondrasik blamed his microphone problems on the Yankees, and Maroon frontman Adam Levine was barely able to delay his hissy fit until he exited the stage.
With multiple sound systems to set up and break down during the course of a night, technical issues are unavoidable stumbling blocks at radio-station blowouts. Utterly avoidable, however, was the mind-numbing loop of advertisements that repeated during every between-set break. By the sixth showing of the "Shark Tale" trailer and the umpteenth cautionary promotion for ovarian-cancer screening -- a dubious choice of subject matter for a pop concert in the first place -- many fans were vocally gearing up to boycott both.
On a happier note, Los Lonely Boys, Willie Nelson's Tex-Mex proteges, were the breakout band of the night. You wouldn't necessarily know it from the e-z shuffle of "Heaven," the group's radio single, but elsewhere the three brothers burrowed into a vibrant blend of their Latin roots and raucous roots-rock, loosing sweet, tight harmonies, screaming blues guitar, and a pummeling rhythm section -- graceful and gritty in equal parts -- that combined into an irrepressibly joyful noise.
It would be impossible to overstate the impact, after five hours (with the above-mentioned reprieves) of T-shirts and sneakers, falsettos and major-7 chords, of Lenny Kravitz, who swaggered in at 10:45, feathered and fringed, throat choked with pearls and hips pumping, careening across a purple-bathed stage into a high-wattage horn-stoked take on "You Got Me Running." In this context, Kravitz transcended what might on another night have been perceived as familiar poses and stiff riffs and anointed the arena like a true-blue rock 'n' roll revelation, a sex god among singer-songwriters, and the show's salvation.
His energy was, by any standard, completely uncorked. Kravitz canceled his fall US tour, citing family matters, and it seemed for all the world that the MixFest crowd was the lucky recipient of the spark and the heat that Kravitz otherwise would have had to parcel out over the course of several months. And he was a benevolent MixFest ruler, showering the fans with the hits they came for, among them "It Ain't Over 'Til It's Over," "Fly Away," his remake of the Guess Who's "American Woman," and a fuzz-drenched, set-closing "Are You Gonna Go My Way?"
Joan Anderman can be reached at anderman@globe.com.![]()