Staff Benda Bilili are a Congolese octet whose second album, "Bouger le Monde," was produced by Vincent Kenis of Congotronics fame. Fronted by five polio survivors who met as beggars outside the Kinshasa zoo, four in wheelchairs and a fifth on crutches, their name means Look Beyond Appearances. The other members are a spry drummer and an imposing bassist in black and a hyperactive kid named Roger Landu who's the inventor and master of a one-stringed lute that sounds like a cross between a theremin and an emaciated steel guitar. On their 2009 album "Trés Trés Fort," that eerie lute defined what seemed like an excellent novelty group. But then I saw them at Denmark's Roskilde Festival in July and said holy mackerel. On Oct. 18 at Symphony Space, the New York stop on their first American tour, either they were still better, I noticed more details, or both.

I Saw Springsteen Surpass Staff Benda Bilili

This is a spectacularly original and well-conceived band. Not one member is a virtuoso, although high tenor Theo Nzonza comes close and Landu's satonge provides a version of the liftoff soukous fans used to get from its interlocking guitar maestros. But everybody sings, most write, the two guitarists are a team, and the bass and drums generate rock stomp alongside Latin lilt. Most important, all eight musicians individuate themselves. After Nzonza and baritone Coco Yakala Ngambala are established, titular leader Ricky Likabu, one of two obvious over-60s onstage, slows into what the program calls "an exhortation to the people of Africa to stand up and repossess their own resources" ‑- which turns barn-burner soon enough. The other old guy, Djunana Tanga-Suele, sings from the floor after ditching his wheelchair to dance on his knees, grinning intently all the while. And in case you suspect the bassist and drummer are on board solely for heavy lifting, they share a strikingly gruff and admonitory lead on a song the drummer wrote.

Although Nzonza's vocals keep getting richer and floor leader Landu is on his way to developing singing skills worthy of his vitality and grace, the standout was someone I didn't fully register at Roskilde: on crutches to the right, in the golden-yellow T-shirt and black patent leather shoes, animateur Kabamba Kabose Kasungo. The animateur is Congolese music's hype man ‑- not a singer, an interjector. Kasungo juices the beat with shouts, exclamations, bits of chorus, and animal noises and adds visual excitement by shaking, contorting, and bump-and-grinding within his inescapable wooden support system, sometimes pivoting on his stiff left leg as he shakes his shrunken right. The wheelchair guys all dance within the chairs they also roll around in, and are heroic in their will to produce so much voice from a sitting position. But Kasungo is as dauntless a showman as young Landu himself. When he doffs his wool cap to reveal a hairless pate, it seems like part of the entertainment.

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The classic soukous of Mobutu Sese Seku's evil heyday was world-class escapist pop, some of the greatest ever. Sparer and rougher, Staff Benda Bilili don't aspire to such shows of luxury. But they do place a premium on physical energy, and thus their 100-minute show never dipped for more than a few minutes into the kind of lull most musicians schedule in to catch their breath. Before the penultimate song of the show proper ‑- there was a generous encore ‑- animateur Kasungo commanded, in English, "Stand up. Stand up." At some shows onlookers resent such demands. But not us. We were looking for an excuse to move to the music anyway. And more important, we knew what Kasungo really meant: "Stand up. Stand up. You can."

So we all did.