After receiving some uncomfortably mixed reviews for their latest album, Catharsis, Machine Head could have embarked on their latest world tour with major concerns about the state of their reputation. The cheering reality is that virtually every show on the Oakland quartet’s current tour has sold out, including two nights at the Roundhouse.

Billed as “An Evening With ...”, there is something gently revolutionary about the way Machine Head have abandoned standard package tours and festival slots, preferring to eschew support acts and play for the best part of three hours every night. It’s an approach that suits them perfectly, partly because they have a catalogue big enough to make it work but also because frontman Robb Flynn’s lyrics have taken on a furious political edge of late, subtly isolating the band from their peers in the process.

Emerging in front of a stark, ghostly backdrop and launching into the bullish, dramatic Imperium, tonight feels like a victory for Flynn’s crew from the start. Friday night’s crowd had been a little subdued, but Saturday’s is anything but: the swirling mosh pits that erupt during the post-Charlottesville tirade of Volatile are but an hors d’oeuvre for the explosion of crowd-surfers, circle pits and startlingly loud singalongs that steadily build in strength through the show.

It’s the classic, heavy tracks that have the most impact, of course. Now We Die, Ten Ton Hammer and Locust all fly by in a blur of limbs and airborne beer. After 25 songs and nearly three hours, Flynn conducts the audience through the dark and brutal but thrillingly euphoric Halo and, for a few thunderous moments, Machine Head seem like the only current metal band who really matter.