When Swans last played Tokyo in 2013, the venue itself seemed to be groaning under the weight of the onslaught. Two hours into a set of tempestuous rock catharsis, the power cut out; once restored, the group kept playing for another 30 minutes.

Such marathon gigs are the norm for Swans, the avant-rock ensemble founded by Michael Gira over three decades ago. How on Earth do they keep it up?

"It's like a construction worker going to the job site, you know?" says Gira, speaking over Skype from his home in New York state. "You just dive in and do the work. We push ourselves, and the music, as far as we can each night. I'm not implying that it's a heroic undertaking, by any means, but it's sort of our job, to try and really let the music inhabit us."