A rebound relationship is always a tricky proposition. And it’s one that nascent duo Broken Bells — which teams newly single artists James Mercer and Brian (Danger Mouse) Burton — are forced to deal with in multiple ways, musically exploring broken past relationships while delicately forming a new partnership of their own. Playing their fifth-ever live set at the Troubadour on Sunday, the two displayed convincing glimpses of the long-term indie-pop powerhouse they could easily become but remained a bit too tentative to fully commit.

The collaboration seems strange on paper: Former Shins guitarist-singer Mercer is an introverted tunesmith and lyricist cut from the classic coffee-shop-confessional cloth; Burton (Gnarls Barkley, Danger Doom) is a hip-hop-bred producer and multi-instrumentalist with a fetish for psychedelic flourishes and off-center synths.

Yet their superb self-titled debut, released March 9, discovers surprising affinities between their personalities, grounding Burton’s stylistics in melancholy songcraft, and enlivening Mercer’s monochromatic tendencies with splashes of Technicolor weirdness.

Shame, then, that much of Sunday’s show colored over the record’s experimentation with studious perfectionism, with Mercer and Burton (here switching between drums, guitar and organ) augmented by four additional musicians who adroitly reassembled the record’s nuanced layers, yet were prevented from adding anything more. Performing on a dimly-lit stage and making precious little small talk, the band spent just under an hour charging through all of the album’s tracks, and in roughly the same order.

At times this straightforwardness served them well. On piano-driven pop tune “October,” the band sounded like Coldplay’s scruffier, sexier cousin, while Mercer’s funky falsetto-showcase “The Ghost Inside” finally prompted key members of the crowd to cease politely nodding and reorientate their bodily movements further southward.

Yet the aptly titled “Sailing to Nowhere” came across in concert like a series of false starts, as the band attempted several variations of the same chord progression, but couldn’t get any of them to stick.

An extended take on album standout “The Mall and Misery” was carefully engineered to built up a propulsive head of steam, though one sensed that a little dash of recklessness could have pushed it up well beyond the rafters.

Despite reportedly sitting on nearly a dozen unreleased songs, Broken Bells opted to run through a pair of covers during the encore: Neil Young’s “Don’t Let It Bring You Down” and My Bloody Valentine’s “When You Sleep.” The former was lovely, while the latter revealed just how badly this band could stand to cut loose once in a while.

With an imminent pair of SXSW showcases and a full tour on the horizon, there’s every reason to believe they’ll get their mojo working soon enough.

Broken Bells

Troubadour; 500 capacity; $25

  • Production: Presented by the Troubadour. Reviewed March 14, 2010.
  • Crew:
  • Cast: Band members: James Mercer, Brian Burton (Danger Mouse), Nate Walcott, Nik Freitas, Jonathan Hischke, Dan Elkan. Opening act: Dot Hacker.
  • Music By: