The crowd at the Starlight Ballroom on Tuesday night cut off the view of Bethany Cosentino at the waist, but in case you couldn't see what she was wearing below her gray tank top, the Best Coast singer started the show by announcing her outfit: sweat pants and high heels.

That mixture of comfort and style neatly encapsulates the band's sound, which swaddles airtight melodies in a layer of cozy lo-fi fuzz. Drawing handfuls of inspiration from '60s pop singers, Cosentino sings in the lonely voice of a girl stuck in her bedroom, waiting for the right guy - or, failing that, any guy - to call. Her version of Lesley Gore's "That's the Way Boys Are" was less an homage than a thesis statement.

At 23, Cosentino, a former child actress whose father played in the band War, is a grown, or at least growing, woman, one whose long-term relationship with Nathan Williams of the like-minded opening band, Wavves, is the indie-rock equivalent of Justin Beiber dating Selena Gomez. But there are no women, or for that matter, men, in Best Coast's songs, just girls and boys fumbling their way through an adult world.

At times, Cosentino's plaintive vulnerability was bracing, even revelatory. It would be easy to write off lyrics as simple as "I wish he was my boyfriend" as diaristic drivel, but the effect was of an emotion stripped to its elemental form. In "I Want To," she repeated the phrase "I miss you so much" over a thumping two-chord riff until it became a primal stomp.

Best Coast, which also includes guitarist Bobb Bruno and drummer Ali Koehler, has its blend of summery shimmer and echoing haze down to a science. But over the course of a set that lasted more than an hour, the formula started to wear thin. A misguided attempt to shift the mood with a discordant cover of Loretta Lynn's "Fist City" only threw the band's limitations into starker relief. Cosentino may admire Lynn's assertiveness, but she didn't sound even slightly capable of following through on the song's threats.

Aggression wasn't a problem for Wavves, which onstage come off more like a tuneful hard-core band than the weedy whiners of record. Williams pushed his nasal voice to the limit on "Idiot," stumbling through amiably incompetent guitar solos while his rhythm section roared behind him. There wasn't much variety to that sound either, but they were on and off stage quickly enough that no one was the wiser.