Charles Ives purportedly once said, "You've got to learn to stretch your ears."

Tom Orr listens to the latest ear stretching work by composer Adam Rudolph and his ensemble, and Michael Stone takes you on a sonic tour of Creative Music Studio's archive of improvisational music (which includes another Rudolph ensemble).

Go: Organic Orchestra Sonic Mandala Meta Music ( www.metarecords.com)

Master percussionist though he is, Adam Rudolph has never been merely a guy who beats on things and creates great grooves. Sure, he can do that in spades, but while he was learning to drum in his native Chicago, he also absorbed a good deal of knowledge about musical structures, arrangements and how rhythm and melody work together in ways both expected and unexpected. His collaborations with notables like kora pioneer Foday Musa Suso and Gnawa great Hassan Hakmoun were marked by a mixture of solid natural beats, fusion-minded openness and music that was as danceable as it was just plain intriguing. Rudolph showed a more experimental, jazzier side with his own band, Adam Rudolph's Moving Pictures, and he's always been a bit ahead of the curve in the world music game.

Among his ongoing projects is Go: Organic Orchestra, 34 diverse players specializing in composed yet “improvisationally conducted” pieces that feature a dizzying array of familiar and unfamiliar instruments (don't doubt for a moment that an electric bass can peacefully coexist with an ewart bamboo horn) moving every which way atop a foundation of layered percussion. The tracks on Sonic Mandala are simply titled “Part One,” “Part Two,” etc., but nothing is simple about the resulting sound. While there's an unmistakable African air in the polyrhythm, a true global journey quickly ensues with shades of everything from free flowing jazz and stately classical to atmospheric interludes that eliminate gaps between countries, cultures and musical genres.

If I'm giving the impression that the music on this disc is borderline impossible to describe, that would be precisely what I'm looking to put across. And if it's possible for music to be simultaneously wild and reined in, Sonic Mandala is that possibility realized. I would love to see an adventurous dance company take this stuff and come up with some equally bold choreography that would do it justice, since it practically cries out for visuals. A few meandering and cacophonous moments aside, this is a uniquely engaging treat from beginning to end. -Tom Orr