Boston’s Guster has been around for more than 10 years, quietly making records full of non-threatening folk-rock with just acoustic guitars and hand-percussion as instrumentation. It’s a recipe for cult success, and that’s what they’ve found; the frat houses of America file Guster’s “Goldfly” on the same CD racks that hold John Mayer’s “Room for Squares” and the oeuvre of Dave Matthews. But on Guster’s new album, “Keep It Together” (Palm/Reprise), the trio has expanded its sound to include bass and a full drum kit. Those additions have actually pushed Guster to experiment beyond their typical strum-and-sing sound, and the highlights of their show all revolved around new material, even as the band played to an audience hungry for the past.
Guster’s current single, “Amsterdam,” is a perfect example of the band’s evolution. Though it explores the same thoroughly mapped three-minute verse-chorus-verse adult-contemporary sound countless bands have in the past (Del Amitri’s “Roll to Me” comes to mind immediately), it’s a smart song, full of lyric subtlety and dynamic shifts. It finds its core in a bass intro that also becomes its breakdown, with a sharp snare hit signaling the start of the verses and a memorable chorus at least as catchy as any of Jason Mraz’s similar-sounding singles.
The band’s old material sounds amateurish now that it’s grown up; there was almost an apologetic tone to audience favorites like “Barrel of a Gun.” But when Guster branches out — as at the close of the show, with an unamplified alt-country take on another new song, “Jesus on the Radio” — the band shows a new, respectable drive to break out and make music that challenges rather than appropriates.
Clem Snide’s been making challenging music for a while, and the band’s eminently likeable opening set concentrated on its new Spinart release, “Soft Spot,” plus witty indie-rock from the New York quartet’s back catalog. Coming off like the less smarmy brother of Cake singer John McCrea, singer Eef Barzelay led the crowd in a sing-along of the typically wry lyric “You’re not as weird/as you’d like me to think” before nailing an irony-thick version of the Christina Aguilera ballad “Beautiful.” Like Clem Snide’s best originals, the novelty didn’t wear off; it speaks volumes about this band that Barzelay doesn’t bite off his tongue as it rests in his cheek.