Though barely a sliver on the map, the island of Cuba holds more musical talent, tradition and influence than nations several times its size.

Stroll through Old Havana on virtually any night of the year, and you'll encounter street musicians who play at a level of virtuosity unknown among counterparts in, say, the United States. Step into downtown Havana's jazz clubs, and you'll hear soloists whose colossal technique and harmonic sophistication dwarf the work of peers around the world.

So even though the "Buena Vista Social Club" film and recording have rejuvenated worldwide interest in Cuban music, Americans hardly have scratched the surface when it comes to encountering the island's most important musicians. Dozens of provocative bands and exceptional soloists have yet to be heard in the States, and as they slowly trickle onto our stages, they force us to redefine the way we hear and judge Afro-Cuban jazz.

The most recent example emerged Tuesday night at the Ravinia Festival's Martin Theatre, where the fabled Orquesta Aragon performed to a capacity house, with additional patrons listening via speakers on the lawn. Those fortunate enough to attend the local stop in Orquesta Aragon's U.S. tour probably were grateful to behold these musicians at close range, in a relatively intimate setting. If the amplification was cranked up too high (the musicians repeatedly signaled the sound technicians to cut the volume), nearly everything else about this performance proved revelatory.

For starters, Orquesta Aragon punctured the prevailing belief that all, or at least most, major Cuban musicians have developed Herculean technique. Though Havana seems to produce more hyper-virtuosos than any city on the planet, Orquesta Aragon generally is not about bravura soloists.

Yes, each of its players has a firm command of his instrument, but none startles the listener the way an Ernan Lopez-Nussa does with his Lisztian pianism or an Orlando "Maraca" Valle can with his astonishing flute improvisations.

In the place of superhuman virtuosity, however, the members of Orquesta Aragon provide some of the most sublime ensemble playing one could hope to encounter from a dozen performers.

Their arrangements, though played from memory in seemingly nonchalant manner, proved extraordinarily complex—particularly when one listened beyond the danceable backbeats that drove much of the repertoire.

The layered rhythms, oddly placed accents, perpetually changing instrumental textures and unexpected stops and starts indicated Orquesta Aragon was playing dance music of a higher order than the term usually suggests.

Throughout the band's intermissionless set, the Cubans proved that dance music needn't be inferior to concert repertoire. The two often merge in the best Cuban music, and Orquesta Aragon underscored the point.

Whether the band was playing historic danzon or traditional bolero, whether the tempo was upbeat or languorous, the orchestrations proved as refined as the melodies were accessible. Because several of the violinists doubled as percussionists and vocalists, a mere dozen musicians created the range of color and depth of sound of a medium-size orchestra.

So adroit is Orquesta Aragon in making arcane musical forms accessible to a wider audience that even the most ancient genres won ovations.

Consider a passage in which five percussionists offered classic rumba—the fast tempo merger of vocal chant and fast-flying beats that frequently spring up on the streets and back alleys of Havana. No sooner had the percussionists established the African tone, however, than the rest of the band chimed in, as if to soften the volatile Afro-Cuban rumba with sweet strings and delicately embroidered flute lines.

For all the ensemble savvy, a few solo turns demand recognition.

Flutist Eduardo Rubio produced silvery arabesques that somehow penetrated the full orchestral sound; pianist Orlando Perez pushed into harmonically daring territory more often than anyone else in the band; and violinist Lazaro Dagoberto Gonzalez proved that Paganini-style pyrotechnics and Afro-Cuban rhythm are not necessarily mutually opposed. And who could resist the high-energy, unabashedly exhibitionistic timbales playing of Inocente Alvarez? At certain junctures he used both shoes as drum sticks, leapt off the stage to rouse the audience and poured bottled water over his bald head in a kind of jazz baptism.

Unlike many of the world's great musicians, the Cubans clearly don't take themselves too seriously, which only makes them all the more appealing to the uninitiated.