MUSIC REVIEW : AMM Finds Wonder in Pure Improv

Improvisation is an endangered musical species, deemed, in some quarters, to be a kind of obsolete relic of the revolutionary ‘60s. In fact, improvisation is the world’s oldest musical profession and also one of its most renewable resources. And absent jazz’s swing, it can even serve “serious” music.

There were no musical scores or structures to obey when pioneering British group AMM made a rare Southern California appearance Tuesday at the Ivar Theater, the first of two nights. A program was handed out, promising--truthfully and cryptically--one thing: “Improvisation.” That it was, 90 beautiful and unbroken minutes of exploratory musings.

AMM, founded in 1965, left its influential imprint on such notable British experimentalists as avant-guitarist Derek Bailey, composers Gavin Bryars and Michael Nyman and thinker-producer Brian Eno. Here, charter members Eddie Provost on percussion and Keith Rowe on “prepared guitar” were joined by pianist John Tilbury. Mixing intellectual detachment and primitive noisemaking instincts, the trio managed to create an extemporaneous suite of compelling, abstract, even meditative music.

Rowe, in some ways, had the most tricks up his sleeve. He treated his table-bound electric guitar with all manner of objects, striking, sliding over and bowing the strings, with an actual bow and the magnetic-powered “e-bow.” At one point, he coaxed a wondrous sonic haze by using steel wool and a hand-held, battery-operated fan.

Meanwhile, Provost splashed and caressed his drum kit, sometimes bowing cymbals for an overtone-rich braying sound, and Tilbury issued gentle phrases with a distracted, half-awake lyricism--like New Age meanderings turned, gratefully, inside out. Together, they carved out a resonant, interactive space in which to converse. Unhindered by linkages of harmony or rhythm, they evoked a deeper mode of communication.

In lesser hands, this could amount to unmitigated murk; here, the result was a symbiotic, joyful noise. By the end, the players splintered off into an exquisite silence, which a rapt audience was hesitant to disrupt with applause.

It was that kind of evening, as unforgettable as it was, by definition, unrepeatable.