According to one theory of pop music, it all comes down to the song. That proposition doesn't explain much contemporary indie-rock, which relies heavily on texture and groove, but it does work for Nada Surf.

The New York-based trio filled the Black Cat onTuesday night, primarily because of such tunes as the rollicking "Blankest Year" and the pensive "Blonde on Blonde." The crowd certainly wasn't there because of the band's stage presence.

Singer-guitarist Matthew Caws began several songs more or less solo, and opened the first of two encore sets by performing the gentle "Your Legs Grow" without his band mates, bassist Daniel Lorca and drummer Ira Elliot.

Things were livelier when the rhythm section was included, of course, but it was the material that carried the performance. The arrangements were merely functional: Caws's high tenor sometimes strayed higher, Lorca sang in unison on some choruses and the occasional "yeah," and Elliot thumped harder than the folkie-rock songs required. But there wasn't a dud in the set, which drew heavily on the group's latest album, "The Weight Is a Gift."

Perhaps because the gig came early in the band's current tour, the musicians didn't seem especially attuned to one another's playing. When they returned for the apparently unexpected second encore, they performed songs that sounded unrehearsed, and didn't offset the sloppiness with empathetic interplay. Still, the song-oriented Nada Surf making some unruly noise was an agreeable change of pace.

-- Mark Jenkins