Lest it be left unsaid: NOMO maymake you get down, but they are serious dudes. A glance at bassist Matthew Golombisky, who has f-holes tattooed on his forearms, or baritone saxophonist Dan Bennett, who plays his instrument like he’s operating heavy machinery, will tell you exactly that. Not that they’re overly studious: These guys are the jazz heads at every music conservatory who’d rather be trading solos with Fela Kuti.

The great Nigerian bandleader’s mid-’70s Afrobeat casts a large shadow over NOMO‘s often electronic take on the genre. The Ann Arbor, Mich., group — currently a sextet led by alto saxophonist Elliot Bergman — played an electrifying, hour-plus set last night at DC9, and it was easy to pick out other influences, too, from fusion-era Miles Davis to the recent ambassadors of Afrobeat coming out of Congo, the Saharan, and Lisbon, Portugal. Everything blended seamlessly but each component remained distinct — less like a melting pot, as Bergman suggested in an interview last year, and more like, say, an overstuffed sandwich.

Drawing largely from its recent albums Ghost Rock and Invisible Cities (parts of both come from the same sessions), NOMO frequently employed tension as the counterpoint to chaos. Several times, the group established a hummable fanfare (the main melody in “Waiting” struck me as a ’70s cop-show theme with a steel spine), cooled down for a couple of de rigeur solos, and exploded into a caterwauling, free-jazz-style coda (my thoughts frequently turned to Eric Dolphy).

Programmed beats and thumb pianos (Bergman had three of these) suggested the percussive junkyard-industrial songs of Konono N°1, while guitarist Erik Hall, probably the loosest player of the bunch, channeled the exuberant and fluid Taureg style championed by bands like Group Inerane. Often, when trumpeter Justin Walter found a Latin-sounding melody, and when Bergman used a pair of pedals to produce laser-beam noises, the grimy dance music of Angolan-Portuguese groups like Buraka Som Sistema emerged.

What held it all together, and what makes NOMO sound like NOMO, were the rhythms, all hulking, robotic, and intimidating. As fun as the group is, its music has a weightiness — a heaviness, really — that can defy easy identification, at least until you notice how hard bassist Golombisky and drummer Quin Kirchner are playing. And they had help: When Hall put down his guitar to assist on drums and percussion, polyrhythms practically became omnirhythms. Once or twice, toward the end of the set, Bennett’s baritone hovered below the main melody for a moment before erupting into a burplike counter-rhythm. Those in attendance — by the end of the set, many of whom had taken to tables and chairs — didn’t stop moving for a second. (During a cover of Sun Ra‘s kitschy “Rocket No. 9,” they even sang along.)

A heaviness, too, lurked beneath the music of the evening’s opener, D.C.’s Last Tide. The four-piece’s morose, atmospheric pop suggested a love of all things pre- and post-shoegaze, but guitarist Nate Frey’s oratorical baritone and bad-weather imagery reminded me more of Swans‘ dark-hued art pop or Tindersticks‘ more downcast material than the influences (My Bloody Valentine, Slowdive, Red House Painters) that Last Tide lists on its MySpace page. Even a cover of Talking Heads‘ “Memories Can’t Wait” — abetted by keyboardist Libby Dorot’s spectral backing vocals (she sang lead on several other songs) — was pulsing, ominous, and nearly perfect. The group drops its debut EP in September.

The evening didn’t end with an encore, but I doubt anyone in the audience walked away disappointed — not surprising, given that NOMO ended its set by parading onto the venue floor. There, the members eased into a brassy dirge and faded out, surrounded by the crowd’s sways and “whoa-oh” chants. Perhaps for a group so propulsive, release only works as a come-down.

Photo courtesy of NOMO’s MySpace page