Concert preview: Mastodon at Express Live outdoors

Andy Downing

Even two years after she passed away, Mastodon guitarist Bill Kelliher still finds himself picking up his cellphone on a near-daily basis with the thought of calling his mother, Cathy, who died of a brain tumor in 2016 as the band wrapped the recording of its most recent full-length, Emperor of Sand.

“Now, if I'm driving and I go to pick up the phone and call her like I used to, she's not there anymore, and I can't talk to her, and it sucks,” Kelliher said. “I think of her every day and wish she was still around. … It's unfair. She was such a healthy person and a wonderful person, and cancer took her.”

Kelliher and singer/drummer Brann Dailor sketched out early demos forEmperor of Sand while both cared for mothers diagnosed with cancer. According to the guitarist, the two started most sessions the same way, sharing coffee and inquiring about the other's situation.

“The first thing out of our mouths would be, ‘How is your mom doing?' ‘Oh, she's got chemo later,'” said Kelliher, who joins his bandmates opening for Primus at Express Live on Tuesday, June 5. “This was on our minds and … it seeped into the lyrics. It was the giant elephant in the room.”

The members of Mastodon are no strangers to the concept record, having previously crafted metal/hard rock opuses centered onMoby Dick (Leviathan, from 2004) and wormholes, astral travel, Tsarist Russia and the passing of Dailor's sister, Skye, who died of suicide at age 14 (Crack the Skye, 2009). But whileEmperor of Sand contains fantastical elements — songs center on a desert wanderer marked for death — the lyrics have real-world ties.

“We're taking all these situations where someone is dying of cancer and instead of saying, ‘I'm getting radiation,' it's, ‘I'm trying to get away from the sun in this dry desert,'” Kelliher said. “We sort of built this story around what happens to you when your body starts disintegrating.”

On “Roots Remain,” the album's emotional centerpiece, Dailor and bassist/singer Troy Sanders trade passages about fading beauty and decay, Sanders howling, “We resolve and watch as it all crumbles down.” It's a track that still resonates with Kelliher when the band performs it live.

“The song basically talks about your body withering away … and all I can think about is my mom laying in hospice,” he said. “We were playing a gig [on Mother's Day this year] and I almost lost it. I was tearing up like crazy and I said on the microphone, ‘Happy Mother's Day, mom, and to all of you out there, cherish your mothers.' Then I think [singer/guitarist] Brent [Hinds] said something like, ‘Fight for your right to party.' … He was just oblivious, but that's just how it is in our band.”

For the more streamlinedEmperor, Mastodon again teamed with producer Brendan O'Brien, who previously helmedCrack the Skyeand whose presence again served notice the band wouldn't be content to explore comfortable musical terrain.

“As soon as people heard we were going to do a record with Brendan O'Brien it was like, ‘Oh, you fucking sell-outs. … He's going to put keyboards all over your record.' And it was like, ‘Fuck off. Everybody fuck off. Eat a bag of shit,'” Kelliher said. “You can't keep putting the same record out. So many people are stuck, like, ‘Oh,Remission [from 2002], that was your best record. You should have kept writing like that.' … Yeah, that was cool, but it was [written] 18 years ago when I was a whole different person and we were a whole different band, and you have to accept that. People mature and they grow. That's how life goes.”

Express Live outdoors

6 p.m. Tuesday, June 5

405 Neil Ave., Arena District