BY MELISSA RUGGIERI

Blue lights throbbed and dry ice clouded the stage as alt-J singer Joe Newman crept into “Hunger of the Pine,” the first entry of the band’s sold-out show at Chastain Park Amphitheatre on Saturday.

It's been only two years since the college chums from Leeds, England first visited Atlanta for a packed show at The Masquerade (they swung through later in 2013 for a gig at The Tabernacle). And while it's still challenging to embrace their music in a live setting, the band has augmented their presentation with a searing visual display to complement the chiming guitars, Afro-pop rhythms, chanting vocals, chatty cowbells and hazy keyboards that color songs from their 2012 Mercury Prize-winning debut, "An Awesome Wave" and the follow-up, last year's "This is All Yours."

Keyboardist Gus Unger-Hamilton and singer/guitarist Joe Newman were the centerpiece of most songs. Photo: Robb D. Cohen/www.RobbsPhotos.com.

Credit: Melissa Ruggieri

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Credit: Melissa Ruggieri

Narrow, horizontal video panels flickered with artsy patterns and spinning lighting rigs provided some stimulation. These visuals are a necessary addition considering that the band barely moves onstage – touring bassist/guitarist Cameron Knight was particularly stoic – and is playing a series of sellouts in arenas (commendably, they filled  Madison Square Garden earlier this week), amphitheaters and festival stages on a tour that now extends through October.

Their music is undeniably tricky and twisty – drummer Thom Green is an unsung hero busily constructing beats on his cymbal-free kit – but Newman’s steady hum of vocals didn’t exactly equate to easily discernable lyrics. Not that the young crowd didn’t happily roar at the first lines of “Fitzpleasure” or shout the refrain of “This is from Matilda,” from the melancholy, cinematic-referencing “Matilda.”

The latter brought a slight smile to the corners of Newman’s face, but otherwise he remained laser-focused on singing – harmonizing well with keyboardist Gus Unger-Hamilton – and playing guitar.

Unger-Hamilton played emcee for the night, graciously thanking the audience several times for their support, but never moving beyond cursory interaction.

As he stood a couple of feet from the keyboardist’s left side, Newman injected “Left Hand Free”– one of alt-J’s more standard-structure songs – with a touch of buzzy blues and, with Unger-Hamilton, unveiled a welcome dose of falsetto on “Bloodflood, pt. II.”

The band brought a sell-out crowd to the first show of the season at Chastain. Photo: Robb D. Cohen/www.RobbsPhotos.com.

Credit: Melissa Ruggieri

icon to expand image

Credit: Melissa Ruggieri

Some of the band’s material, such as the original “Bloodflood” from their first album, drifted into the air as shapeless ambient music. But other songs – the funk-lite “Every Other Freckle” and the prayerful “Warm Foothills” in particular – mesmerized with a combination of intensity and introspection.

After enlivening the crowd with the steady march of “The Gospel of John Hurt,” the band returned for an encore that launched with their dreamy, almost unrecognizable version of Bill Withers’ exuberant “Lovely Day” and ended with the quirky, rhythmically shifting “Breezeblocks.”

Alt-J – named after the pyramid-like symbol from the alt-j shortcut on a Mac – is still a band better enjoyed as a headphones experience. But while their music lacks the standard peaks and valleys that guide most concerts, it flourishes in its own artsy world.

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