Photo courtesy Nuclear Blast
THE PROGRESSIVE BLACK-METAL band Keep of Kalessin was founded in Trondheim, Norway, home of one of the country’s leading music conservatories. Yet for the longest time, Keep of Kalessin guitarist Obsidian C. could not find a regular drummer for the group he formed in 1994.

Blame it on the school’s dedication to jazz, whose tippy-tappy approach to percussion is the opposite of extreme metal’s sharp snare snaps and double-bass-drum roar. That doesn’t mean Obsidian has anything against the Norwegian University of Science and Technology‘s famous music school.

“I actually studied at the music conservatory when I was a lot younger,” he said. “I studied four years of classical guitar and then four years of electric guitar. My problem was I never really rehearsed what I should rehearse; I just wanted to play my own stuff.”

But the school kept track of Obsidian, and last year Keep of Kalessin was invited to play a collaborative show at the conservatory’s jazz festival with the experimental duo Monolithic.

“It has taken some time, but Norwegian metal, and especially Keep of Kalessin, has gotten a very good reputation in the jazz scene in Norway,” Obsidian said.

Named after a dragon’s lair in Ursula K. Le Guin‘s “Earthsea” series, Keep of Kalessin has released just four albums in its career, due mostly to frequent band turnover and Obsidian’s five-year stint as touring guitarist with black-metal giants Satyricon. But Keep of Kalessin has managed to release two incredible records since 2006: The pulverizing “Armada” and its new, more diverse yet no less powerful sister CD, “Kolossus” (Nuclear Blast). (Together they make up a saga about wars against the gods.)

Compared to most extreme metal — where the “roll” part of rock ‘n’ roll is often ignored in favor of an almost suffocating precision (usually abetted by computer processing) — Keep of Kalessin downright swings, and its albums feature relatively little post-production editing.

“We have that rock ‘n’ roll approach to playing our metal side,” Obsidian said. “In our live shows, as well; we never have everything just perfect. We just play on atmosphere and on feeling.”

Actually, that almost sounds like jazz.

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Photo courtesy Nuclear Blast