BY MELISSA RUGGIERI/AJC Music Scene

At 8:15 p.m. sharp, The Avett Brothers crept onto the darkened stage, and, as they have been doing the past few concerts, plucked the opening strains of Soundgarden’s “Black Hole Sun.”

Even though the Avetts are rooted in the Americana-bluegrass-folk-rock associated with their hometown in North Carolina, this is a band that thrives on musical calisthenics, so why not offer a haunting, cello-accented homage to Chris Cornell?

For the next two-plus hours, the gaggle of musicians spread across the stage – Scott Avett (banjo and vocals), his brother Seth Avett (guitar and vocals), Bob Crawford (standup bass), Joe Kwon (cello) and touring accomplices Mike Marsh (drums), Tania Elizabeth (violin) and Paul Defiglia (keyboards) – romped through a 28-song set list that admirably spanned their nearly 16-year career.

 Scott Avett leads a revival. Photo: Robb Cohen Photography & Video /RobbsPhotos.com

Credit: Melissa Ruggieri

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Credit: Melissa Ruggieri

Of course, since this was the first of three nights at the Fox Theatre – the Friday and Saturday shows are nearly sold out and this Thursday gathering was impressively full – the set list and fan experience will certainly change.

It’s a simple setup – a few rugs on the stage floor, pretty pastel-colored search lights that roamed the crowd periodically and the band’s name and “True Sadness” album reference in lighted script behind them – which suited their earthy vibe.

The band performed most of the songs from last year’s Grammy-nominated “True Sadness,” but also reached back to 2003 with “Sorry Man” –the brothers sharing a mic under a solo spotlight – and represented the latter part of the decade with the banjo-centric “Paranoia in Bb Major” and the rollicking “Head Full of Doubt/Road Full of Promise.”

Amid these rootsy treasures, the Avetts sprinkled some covers, including their sumptuous, soulful rendition of George Harrison's "Give Me Love (Give Me Peace on Earth)" ( thanks, guys! ) and an encore that included the sit-down strummer "Make Me a Pallet on the Floor," popularized by Doc Watson, and "The Coo Coo Song."

Whether getting loose and funky on “Ain’t No Man,” drawing “Down with the Shine” to a delicate conclusion or eliciting a cheer at the lyric, “My life is a joke and my bathroom's a bar” during “Smithsonian,” the band presented a taut sound and robust vocals, regardless of which Avett was singing lead.

While many of the band’s songs can feel similar when presented in a compressed time frame and those lead vocals of both Seth and Scott were occasionally overpowered by the music, there was no questioning the joy emanating from the Avetts on stage.

 The Avetts keep it simple, but fun. Photo: Robb Cohen Photography & Video /RobbsPhotos.com

Credit: Melissa Ruggieri

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Credit: Melissa Ruggieri

The snake-hipped Seth constantly rocked or jogged sideways while strumming his guitar to the title track of “True Sadness” and the band playfully interacted with each other between the foot-stomper “The Fall” and the somber ballad, “All My Mistakes.”

The Avetts engender a warm, communal feeling, as if they’re playing with you, not at you, and their diverse, adoring crowd returns the love through every shouted lyric and hand clap.

“This has been one of the kindest cities to visit,” Scott Avett said early in the show. That kindness was demonstrated to these longtime Atlanta Braves fans before the encore, when the crowd broke into the team’s “Tomahawk Chop” chant to lure them back to the stage.

As if they wouldn’t have returned, otherwise.

The Avett Brothers have tweaked and expanded their sound during the past decade to the delight of some fans and disappointment to others.

But trying a different path should be applauded if it helps a band retain its gusto – and no doubt The Avetts are exploding with enthusiasm right now.

The Avett Brothers perform again at 8 p.m. Friday and Saturday at The Fox Theatre. Tickets are 39.50-$59.50. Fox Theatre, 660 Peachtree St. NE, Atlanta. 1-855-285-8499, www.foxtheatre.org.

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