This is an archived article that was published on sltrib.com in 2017, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

Prog-metal leviathans Mastodon have done it all a time or two. "Emperor of Sand," released March 31, is their seventh studio album in 17 years. They've toured the world countless times in that span.

But when bassist Troy Sanders, who doubles as one of the group's three vocalists, called The Salt Lake Tribune from Missoula, Mont., just hours away from the opening show of a five-week run, he confessed he was in the throes of some combination of eagerness and anxiousness.

"Tonight's our kickoff for our tour, so we've got the nerves. The butterflies just arrived and landed inside my belly!" he said with a laugh. "This is the biggest, most adventurous headlining tour we've ever done. We're playing a lot of songs tonight that we've never played before. There's a little more weight on your shoulders when it's your headlining tour. … The pressure's on! But it's a good pressure. It's a good anxiety. I'm excited and happy to get it going."

And they'll happily keep it going Sunday at The Complex in Salt Lake City.

But while the pretour jitters are an apparent fixture for Mastodon, the quartet have experienced plenty of changes between albums 1 and 7.

"Well, the first record, I was broke, homeless and pissed off. But all these years later, I'm in a much better spot, both mentally and emotionally. And the same with my bandmates," Sanders said. "A week or so ago, I put all of our records on the floor, in order, and I was looking at the discography, and it really reflected this amazing journey that we never expected or predicted. And each album truly reflects where the four of us were every two to three years when each record was released. … It's very natural progressions, we're never trying to write the same record twice, we're always trying to better ourselves as bandmates and songwriters and lyricists and vocalists. We feel like we're still truly ascending the mountain. We're both hard-working and very fortunate, at the same time, to be where we are right at this very moment."

Of course, when Sanders arranges the group's records on the floor a few years down the road, cracking open his "Emperor of Sand" time capsule will unleash some unpleasant memories.

The album's heavy and emotional subject matter largely stems from the shared experience of him, guitarist Bill Kelliher, guitarist/vocalist Brent Hinds and drummer/vocalist Brann Dailor simultaneously seeing loved ones forced to fight off death.

"When we started writing what would become this new record, all of us in the band … had family members with recent cancer diagnoses, all at the same time. It was just this wave of various emotions that came over all of us, and as we were getting together to try to create music, it was obvious that this was weighing on all of our minds. We were all very angry that this was happening — no one deserves any type of horrific, horrendous, stealth, evil disease," Sanders said. "So, it was weighing heavily on us — the idea of time and mortality. Yeah, time and mortality. … That's how this whole record was spawned. We ultimately wanted to turn all of this negativity that was going on in our own personal lives into something … that would shine this sort of beautiful light at the end. Channeling all of our grief and anger and all of our emotions into this, and having the result be something pretty and beautiful that will live forever."

Part of that beauty stems from coming to grips with change being inevitable and so deciding to embrace it rather than fight it. Such a mentality stems not only from life experiences, but musical ones, too.

This past December, Dailor told Rolling Stone he wanted to see the band expand its sonic palette, saying, "We always resort to the heavy, heavy, but I'd like to try to be adult and be able to go out there. When you play acoustically, you're pretty much naked. Do you really want everyone to see that? Maybe we're ready to be naked."

Becoming more varied is a philosophy the rest of the band is on board with, Sanders said.

"Yeah, the four of us are rooted in very heavy music, that's what brought us together to form this band 17 years ago. But we have very eclectic tastes, and we love all sorts of music under the sun. … We love keyboards and we love '70s prog rock, we love classical music, we love blues, we love bluegrass, and we love '80s pop music — there's so much that we appreciate!" he said. "We're not afraid to reach out and branch out and be multidimensional. … Basically, we have the freedom to do whatever we like, and that's one of the beautiful things about being in our band. We never signed a contract that says we need to be a heavy metal band 100 percent of the time. We're free to explore, and that's what being in a band's all about, and what playing music should be all about."

Looks like there are plenty more reasons for butterflies in bellies yet to come.

Twitter: @esotericwalden —

With Eagles of Death Metal, Russian Circles

When • Sunday, doors at 6:30 p.m.

Where • The Complex, 536 W. 100 South, Salt Lake City

Tickets • $34.50; Smith's Tix