Jazz avatar Don Cherry shared his beatific smile and warming spirit with 3 dozen Washington musicians Thursday when they came together as an instant orchestra at d.c. space. "The different sounds we make are voices happening," the soft-spoken Cherry explained as musicians drifted in one or two at a time. "We just compose with them."

The D.C. Jazz Workshop Orchestra (which will perform at the Pension Building tonight with Cherry, saxophonist Julius Hemphill and percussionist Nana Vasconcelos as guest soloists) responded in many voices, even in the warming-up sounds of drum heads being tightened and reeds being wetted. It was the little orchestra that grew over four days of intense rehearsal: four electric guitars, a dozen saxophones, three full drum kits and assorted conga players (and one percussionist playing a toy monkey playing cymbals), one banjo, one synthesizer, muted trumpets, flutes. Like the Metro at rush hour, d.c. space filled up with instruments and players at each instructional stop until there was absolutely no more room; a stand-up bass and a set of vibes arrived a few minutes later and everyone sucked in their stomachs.

"We accepted everybody that wanted to play music," Cherry said graciously. "They know what music I've been relating to." Cherry, a multi-instrumentalist, composer and teacher, has been on the cutting edge of the avant-garde since his late-'50s work with Ornette Coleman. More significantly, he has traveled around the world absorbing the music and instruments of many nations and incorporating them into and expanding the jazz idiom, to the point where he has been correctly called "the world's musical memory."

This was evident in the workshop rehearsals. "We just started off with one tone so we could tune into each other," Cherry explained. "Then we got into two tones, a rhythm from the berimbau a bowl-like Brazilian instrument played with a coin or stone , playing a figure from those two tones. Then we learned a scale on the doussn'gouni a hunter's guitar from Mali with a calabash, six strings and a rattle ."

If that description sounds exotic, it's Cherry's particular genius to make the music earthy, understandable and accessible. The fundamental rhythmic insistence of the doussn'gouni was not much different from a bass pattern played on a piano, simply more primordial. The lean-bodied Cherry was himself an instrument, convoluting into a question mark as he blasted out phrases from his snub-nosed trumpet, chanting the simple melody like a griot or shaman, dancing to the compelling polyrhythms of the suddenly cohesive orchestra.

"We try to find some basic forms that we can all come together on," he said, a concept extended to everyone. Earlier in the day, Cherry encountered blind street singer Flora Molton on F Street; he sat down beside her, pulled out a tin whistle and played along with her basic blues. His workshop method is similarly unpretentious, a basic blueprint for the orchestration of free music -- no charts, simple themes and hand-woven folk melodies brought together organically, "an empty canvas where everybody can paint." The workshops, which Cherry has presented all over the world, are an outgrowth of the decade he spent in Sweden.

"I moved there in 1970 to live in the forest, to experience a certain way of life -- the wood culture, raising children, being active in the community." At the same time that he was investing his music with an earthy, organic sensibility, Cherry became deeply involved with children's theater and music workshops. "I've been working with instrument makers in trying to come up with instruments children could make themselves to improvise on; it's such a good thing if you can make your own instrument. Then children feel that music can flow in their daily life, they can develop the ritual of playing music together, learning music together."

Cherry will soon take up residency in Los Angeles, the result of a grant to work with black children in schools there. "Young kids are not being exposed to a music that is part of their culture. In Europe, black music -- jazz -- is a part of American culture; there's a lot of interest and knowledge, they really know jazz. That's one reason I want to be here in America now. I feel like music is growing. That's what we're trying to do now, here: come together, let people of the community here come to make music and then give it back to the community where everybody's coming from." Cherry smiled with delight, as if that were the most natural idea in the world. In much of the world it is a most natural idea; borders diminish in Don Cherry's music.