Remove the copious tattoos, and the four members of Mastodon don’t look much like rock stars. Guitarist Brent Hinds could pass for a burly, bushy-haired lumberjack; rhythm guitarist Bill Kelliher looks like he just got off work at an auto shop; and drummer Brann Dailor has the lean, clean-cut physique of a distance runner. Only bassist Troy Sanders plays the part with his Rasputin-like goatee.

    But close your eyes, and this blue-collar Atlanta quartet might as well be caped wizards from the heyday of 1970s progressive-rock. The band brought its serpentine arrangements and cosmic imagery to Metro on Thursday, and performed with seriousness and intensity on a relatively bare-bones stage. Mastodon is the metal band of the hour, celebrated for the way it mixes heaviness and melody, artistic ambition tinged with mainstream appeal, and the club was packed with fans. Expect this band to be headlining a much bigger venue on its next trip through town.

    Outside of a video screen which displayed images of astral travel and helmeted warriors, the band didn’t offer much to look at. Though metal’s visual flair can border on the theatrical, Mastodon performs with studious precision with heads lowered in concentration. Outside of the occasional heavy-metal pose --- courtesy of Sanders and his splayed-leg stances --- this band was all business. It played its latest album, “Crack the Skye,” in its entirety. Then it worked backward through its previous albums, offering selections from “Blood Mountain,” “Leviathan” and “Remission.”

    The older material suggested how far the band has come. It was heavy on riffs, and the interplay between Hinds’ racing guitar and Dailor’s rampaging drums was breath-taking, particularly on the closing “Hearts Alive.” But the new material is a step above. Sanders, Hinds and Dailor shared vocals, and their call-and-response patterns and wordless harmonies were nearly as complex as the music. New songs such as “Oblivion” boasted choruses that echoed the anthemic drone of Alice in Chains, while more complex pieces such as the 12-minute “The Last Baron” and the four-part “The Czar” allowed the band to reveal a more spacious and trippy side to their music. Though still sprinkled with the heavy riffs and speed-racer tempos of the earlier material, “Crack the Skye” plays like a dream (or hallucination) with images of death, transcendence and time travel.

    What’s lacking is a genuine sense of personality to match the out-sized ambition of the music. There are no alpha males in Mastodon, no sense of an on-stage leader, no visual focal point. Instead, the band focuses on purely musical expression. They are four art-heads as much as head-bangers. They’re not much to look at, but they’re brilliant all the same.

    greg@gregkot.com

    Metal bands aren’t necessarily known for their sensitivity. And it’s not as though the guys in Mastodon ---- who resemble tattooed auto mechanics more than rock stars --- are used to hugging things out. But their lives have been streaked by tragedy, and on their latest album, the excellent “Crack the Skye” (Reprise), they confront it the best way they know how: by making epic, progressive-minded arrangements that touch on astral travel, out-of-body experiences and the Russian Revolution. Now that’s what I call a high-concept album.

    But the fantastical imagery is rooted in real events. The album is named for drummer Brann Dailor’s sister, who committed suicide when she was 14. Dailor filtered that experience through his lyrics, matching the more introspective tone struck by guitarist Brent Hinds, who wrote much of the music while recovering from a near-fatal head injury. The result was a creative watershed for the band. Emotions welled up in the studio as the Atlanta-based foursome listened to the playbacks of several songs.

    “It wasn’t tough putting those feelings into the music,” Dailor says. “It was tougher to out it, to tell people what it was really about. It wasn’t hard to write, but it was difficult to listen back. There are a lot of powerful moments on this album for myself, and now my parents are hearing this album and reading the interviews and it’s bringing a lot of stuff to the surface.”

    Dailor saw the album title as a tribute to his sister, but the experience of making the album wasn’t cathartic in the sense that he hasn’t been able to move on from her death. “It’s still there,” he says. “But the one positive is that by making this album, and acknowledging that some of the music is about her, it opened up a dialogue that I haven’t had with my father, grandfather and other members of the family. We are now talking about it, which we couldn’t before. It was not a subject you brought up at Thanksgiving or Christmas when everyone was together.”

    At the same time, the drummer strived to make his personal feelings universal through vivid story-telling.  “This is an amazing platform I have, to be creative and to have an outlet, because everyone experiences loss, and they have so many different stories to tell, but they won’t be heard,” he says. “It makes me appreciate what I have with these guys.”

    Mastodon came together in 2000 when Dailor and guitarist Bill Kelliher, who had been playing together in Rochester, N.Y., moved to Atlanta and met Hinds and bassist Troy Sanders. They bonded over a mutual love of progressive rock and metal, as well as jazz and experimental music.

    “We had the band name within a week and we were booking shows in basements before we even had songs,” Dailor says. “We were all coming from a background where it was important to be arty and different, but with Mastodon we wanted to get deeper into songwriting, and walk the fine line where you come up with memorable riffs without being too ‘normal’ sounding.”

    The band’s second album, “Leviathan” (2004), established their ability to tackle weighty subjects (Moby Dick, no less) on an appropriately epic scale. “Blood Mountain” (2006) was just as ambitious, with cleaner production. Producer Brendan O’Brien spiffed up the band’s vocals on “Crack the Skye,” but if anything, it only added to the emotional impact. Rather than hide behind mayhem and muscle, the quartet let its armor down just enough to let the arrangements breathe and the melodies to emerge.

    “For me this record was about exercising control, focusing in on parts, and knowing when to say when,” Dailor says. “That’s a big part of being a drummer. When you come from my busy, busy, busy background, it’s more difficult to put the brakes on. I thought to myself I can’t ruin these songs with lots of fills. I felt like I exercised a lot of restraint, served the songs, the music, and allowed these big open spaces to happen. In the past, I would’ve questioned whether I was doing enough, whether I was playing beneath my abilities. But the emotions in these songs spoke a lot louder. We had to let those emotions be heard.”

    greg@gregkot.com

  Mastodon: 8 p.m. April 30 at Metro, 3730 N. Clark St., $20; etix.com.

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3.5 stars

After making albums about the dangers of the sea (“Leviathan” in 2004) and the earth (“Blood Mountain” in 2006), what’s left except to punch a hole into the heavens? Atlanta quartet Mastodon has become metal’s great new mainstream hope even as they make ambitiously progressive albums. “Crack the Skye” (Reprise), out March 24, is the most daring of their four albums, its intricate story line playing out over multi-part songs such as “Oblivion,” “The Czar” and “The Last Baron” that draw on ‘70s progressive rock, psychedelia and even country music. Mortality provides subtext and adds emotional resonance to the band’s sci-fi lyrics: the suicide of drummer Brann Dailor’s sister Skye and the near-death from a fractured skull of guitarist Brent Hinds in 2007 shade the maze-like narrative. All figure into an epic album about transcending the limitations of time, space and the human body. The lyrics present a Tolkien-like fantasy involving astral travel, spirit-world trysts and Czarist Russia.

At its essence, Mastodon remains a four-piece metal band, but this time its sound is broadened with keyboards, banjo and lots of harmony vocals. There is more actual singing (by three of the four band members) rather than the guttural screaming that passes for lead vocals in most contemporary metal. The band remains somewhat faceless (none of the band members has a truly distinctive voice or personality), which puts the focus squarely on the music. Melodies weave through arrangements that teeter between dream-like drift and a gallop, with drummer Brann Dailor again leading the charge. Though less immediately visceral than its predecessors, “Crack the Skye” is denser, deeper and more emotionally transfixing.

greg@gregkot.com

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