About halfway through Empty Set, Brain F≠ issues a directive that might as well be this punk band's mission statement: "Stop being so damn bored!"

It's one of two choruses on the title track, a nimble but burly blitz that's infectious and unflinching. The line is shouted back and forth by Nick Goode and Elise Anderson, who circle each other in a vicious call-and-response. Bassist Eddie Schneider anchors the song with rumbling heft as Bobby Michaud's wild-eyed cavalcade agitates the rhythm into a dizzying blur. Goode's guitars unleash in serrated gusts while Anderson's cutting coos offer bait-and-switch relief; her sardonic sneer has as much bite as any of the instruments.

Like every offering on this sophomore platter, "Empty Set" is aggressively catchy and defiantly antagonistic, an oxymoronic duality that Brain F≠ accomplishes with an air of effortless precision. For 19 minutes, the band makes boredom feel utterly impossible.

The new album arrives more than two years after 2011's Sleep Rough. Building on that debut's unstoppable momentum, Brain F≠ mitigates its blistering severity, throwing curve balls with irreverent glee.

On the opening "Dry," Goode and Anderson sing the chorus together, elongating syllables after rapid-fire verses, pulling taut against the relentless riffs and rhythms. But they also stagger their delivery, heightening the tension by landing just barely out-of-synch. Anderson's expressive approach is a strength throughout, but it shines brightest on "Fulcrum." Initially, she lilts with insincere sympathy, slipping through the cracks of the group's manic spree. "Poor little rich kid," she taunts in the chorus, flipping on a dime and seething with steely fury.

Empty Set takes Brain F≠'s already exceptional sound to a new pinnacle — a bittersweet reward as it might well be the band's swan song. With members spread out across the Southeast and only one live date scheduled, activity seems to be tapering off. Score one for boredom.