BY MELISSA RUGGIERI

No one would ever call the Zac Brown Band "country" country.

Early hits such as “Chicken Fried” and “Toes” certainly turn up the twang, and the breezy “Homegrown,” a No. 1 on the country airplay charts a few months ago, accentuates Brown’s pleasant tenor.

But the Atlanta-rooted ZBB has long rubbed sonic elbows with unexpected artists — Trombone Shorty, Dave Grohl, Jason Mraz — and continues that trend on its thrilling new fourth album, the aptly titled “Jekyll + Hyde.”

The opening two songs (for those who still listen to albums in the track order as they were intended) — the slick, catchy rocker “Beautiful Drug” and soulful ’70s groove of “Loving You Easy” — immediately alert that the album will zig when expected to zag.

Then there is the muscular crossover rock hit “Heavy Is the Head” with Soundgarden yowler Chris Cornell and, for another dose of auditory whiplash, the lighthearted swinger “Mango Tree,” featuring “Brave” songstress Sara Bareilles.

Stylistically, it’s a direction that ZBB violinist Jimmy De Martini said the band has been slowly moving toward.

“The first album (2008’s ‘The Foundation’) was probably the most country and we were able to reach a core country audience. But as we added members to the band, we started slowly changing our musical style but keeping our roots in country. Our taste is evolving in what we listen to and play, but I’ve always been a little in two worlds. I mostly listened to rock and was a guitarist growing up at the same time I was learning classical violin. But,” he added with a laugh, “I still wanted to play guitar with the Black Crowes or Allman Brothers.”

The Zac Brown Band plans to insert several new tunes into the set list on its tour, which launched Friday in its secondary base of Nashville, Tenn. — locale of its Southern Ground studio — and plays a double shot at home May 8-9 at Verizon Wireless Amphitheatre at Encore Park in Alpharetta.

Zac Brown Band violinist Jimmy De Martini is an avid mixed martial arts athlete in his spare time, but says he now does "a lot of kickboxing with the bag...less stuff with the hands and combat," to avoid injury. Photo: Getty Images

Credit: Melissa Ruggieri

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Credit: Melissa Ruggieri

Even though ZBB spends plenty of time in Music City — the band recorded “Jekyll + Hyde” there over a three-month period — they’re still wedded to the Atlanta area.

De Martini lives in Marietta, not far from where he grew up, and agreed that the VWA concerts are definitely a hometown affair.

“It’s great that we get to bring our kids to the (local) show,” he said. “My son is now 7, so it’s the first time he has friends who like the band. It’s just great to see all the friends and family, and they can also see why you’re gone all the time!”

The band — Brown, De Martini, Coy Bowles (guitar, keyboards), Chris Fryar (drums), Clay Cook (guitar, keyboards, mandolin), Daniel de los Reyes (percussion), John Driskell Hopkins (guitar, banjo, upright bass) and new-ish permanent member Matt Mangano (bass) — will be on the road a healthy portion of 2015, playing a mixture of amphitheaters and the rarefied air of stadiums.

Along with the extensive list of hits to squeeze into a set, the guys are also plotting a new cache of their well-regarded cover songs.

ZBB’s versions of Metallica’s “Enter Sandman” and Charlie Daniels Band’s “The Devil Went Down to Georgia” are perennial YouTube faves (though nothing beats hearing them fire up the songs live), and fans can expect the band to add more to their canon.

“We take it pretty seriously when we do a cover,” De Martini said. “We get down note for note and add our own style, too. A lot of the jam bands we grew up with, like Phish and the (Grateful) Dead, they do a lot of covers. We now see, when you’re out there every night, how playing covers can feel new to us and they’re recognized by the crowd. … I was just reading an email from the band with a list of covers we’re going to try out. We’ve got a brand-new stage setup, so the whole show is going to be redone and you will definitely hear some new covers.”

The Zac Brown Band is one of the few current acts able to fill stadiums as well as arenas and amphitheaters. Photo: Southern Reel

Credit: Melissa Ruggieri

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Credit: Melissa Ruggieri

De Martini, who spent many years at the start of his career in the Athens-based Dave Matthews Cover Band — yes, that’s the name — is also a mixed martial arts enthusiast, though he admits to being a little more cautious these days to protect his hands.

“I go more for the training style. I stop sparring about a month before a tour in case I get an injury,” he said. “I do a lot of kickboxing with the bag, less stuff with the hands and combat.”

With a seven-month tour looming, De Martini has cause to be vigilant — but he also has plenty of reasons for enthusiasm.

“This is the most excited I’ve been to start a tour,” he said. “We’ve got the new album, the new stage, a new single at radio … it’s all good.”

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