After two albums of mostly drifty ambience or acoustic quiet, it feels like it’s been a while since Iceland’s Sigur Rós has flexed any of its muscles. But any fears of the band losing its vitality are quickly squashed by the violent and dirty bass throbs of “Brennisteinn,” the opening track on the harsher and darker Kveikur. The band resurrects its long dormant dark side on “Brennisteinn” and on the excellent title track, while still showcasing its unique and unmatched ethereal atmospheres, arrangements, and singer Jonsi’s soaring choir-boy vocal melodies. Most of the album however, features somewhat more straightforward songs than usual, some almost pop-leaning (“Ísjaki,” in particular), largely eschewing the group’s oft-used, slow-build-to-explosive-climax formula for a charging industrial stomp, often with forceful drums and clanging, metallic percussion (especially with the strings and horns of the almost neo-folk “Hrafntinna”).

It’s nice when a band can surprise you far into their career. Sigur Rós have been at it for a while, and Kveikur shakes things up just enough to provide a nice jolt to the band’s formula. This is easily the group’s best album in nearly a decade.