Forget Kanye West, M.I.A., and Sufjan Stevens. Last year only one album delighted, surprised, and thrilled critics from cool-hunting internet Web zines to National Public Radio, the fickle British press, and beyond. The album, “Congotronics” (Cramed Discs), was made by Konono No. 1, a group of Congolese musicians who play a form of traditional music on makeshift instruments through a scavenged-together amplification system. The members of Konono visited America for the first time last fall, leaving a string of rhapsodic word-of-mouth reviews in their wakes. The outfit returns to North America this summer, and stops in New York for three shows — one at Central Park SummerStage July 23 and two at SOB’s July 24.

What’s so surprising about this adoration is how everybody hears something different in the group’s plinking melodies, circular rhythm patterns, call-and-response vocal chants, and can’t-stop-this-party whistles — plus, its back story is irresistible. The group numbers 12 (including dancers) in its home base, Kinshasa, and featured eight musicians while on tour last year. It is led by septuagenarian former truck driver Mingiedi Mawangu, who plays the likembé, a traditional thumb piano. Basically a hand-held, woodmounted resonator amplifying a series of thin metal reeds sounded by the thumbs, the likembé has a brittle range with a rich but terse vibrato.

The group’s members hail from the Bikongo region of the Democratic Republic of the Congo. They play a variation of trance music on traditional acoustic instruments, a sound that was drowned out by everyday urban bustle when it moved to the streets of the loud capital in the 1970s, virtually robbing it of its entire reason to exist. During this decade President Mobutu pushed for cultural “authenticité,” a campaign to celebrate native identity. And Konono — basically a party band that played weddings, funerals, and outdoor street festivals — merely took its traditional music and expanded it. To compete with the ambient noise of modern life, the group fabricated an amplification system out of musical junk and automobile scraps. The resulting tone of these amplified likembés sounds somewhere between a calypso drum and a Japanese pachinko parlor.

Konono features three likembé players — high, mid, and low range — two vocalists, and three percussionists playing Frankensteined kits that include layers of metal shards. As with other kinds of African music, the goal is to find a groove and stay there. Percussionists hammer out constant, if shaky, rhythms; likembé players sculpt jangling, singsong melodies out of their bluntly distorted tones; vocalists chant spirit-raising dance calls — the group can sustain this nearly breathless, up-tempo vibe for what can feel like days. Its roughly two hour sets last fall typically consisted of only a three to four songs.

That this unique, unclassifiable ingenuity arose in — to Western ears — the so-called musical isolation of Africa, invites the grand, sweeping comparisons bestowed upon it in print. The group’s infectious, agile pulse has been aligned with everything from Fela Kuti’s endurance tests to the all-night dance parties of rave’s halcyon days and the reports of Brazil’s funky favela jams today; from the impromptu neighborhood block party of early hip-hop and Jamaican sound-system dub to the percussive workouts of exploratory Krautrock and late 1960s free-form jazz. That the music remains all and none of the above only adds to its romantic allure. Here is a group of crossbreeding, visionary artists turning DIY out of innovative necessity, a band of wily Harry Partches blooming in a country only recently freed from Mobutu’s one-man-ruled Zaire and, even more recently, marred by insurrection from Angolan and Rwandan rebels, the 2001 assassination of its head of state, and a transitional government dealing with already troubled imminent elections. It’s outsider art with a capital “A.”

To be honest, what Konono No. 1 does can all start to sound the same. Online circulation of MP3s from its 2005 tour and clips posted to the Web site YouTube show a band stretching its signature “Congotronics” songs — the dizzying “Lufuala Ndonga,” the ecstatic “Kule Kule” — into 45 minute odysseys. But that hardly matters. Like the music of Louis Armstrong, Konono No. 1 quite simply makes people happy. And when heard for the first time, the bracing, oddly funky sound is a joyful reminder that Starbucksified “world music” still has breathtaking surprises up its sleeve.

Central Park Summerstage on July 23 (Rumsey Playfield in Central Park) and SOB’s on July 24 (200 Varick Street, between Houston and Clarkson Streets, 212-243-4940).