Rhys Chatham was composing indie classical music decades before it had a name, and when comparatively few musicians were combining the instrumentation of rock with some of the structural moves of contemporary classical composers. His work has confused people over the years. Some rock critics think of him as a founder of noise-rock, and the progenitor of bands like Sonic Youth and My Bloody Valentine. Hearing his performance at the SPACE Gallery on Friday evening, you could see the connection.

But Chatham’s credentials are solidly classical. He studied with the electronic music composer Morton Subotnick and the early Minimalist LaMonte Young. He was a founder, and the first music director, of the Kitchen, a small concert space that was for many years the center of the avant-garde in New York.

He once described his work as “new age music for heavy metal fans,” adding that he considers himself “a standard-bearer of Western European art music, not a rock composer.” Yet it was seeing a Ramones concert, in the late 1970s, that led him to write for electric guitar, bass and drums, instead of conventional chamber or orchestral forces. And the combination of the guitar’s roar and Chatham’s Minimalist impulses led him to create large, slow-moving works that can seem like tidal waves of dense, relentless, loud sound.

Chatham has been based in Paris for most of the last 30 years, but he returns to the United States on tour periodically. His performance at SPACE, he said on Friday, was his first visit to Maine. He offered two works – a solo offering, “Pythagorean Dream,” the title piece of his new recording (due June 3 on Foom, a British label), and an untitled trio with Kevin Shea on drums and Tim Dahl on bass. In both works, Chatham played guitar, trumpet, flute, alto flute and bass flute.

For “Pythagorean Dream,” Chatham uses the Pythagorean scale, a non-standard tuning method built of “pure” intervals (the distance between each half step is identical) rather than the “tempered” tuning (in which compromises in the interval tuning makes it possible to play in multiple keys and still sound in tune) common in Western music since the 17th century. An untempered scale makes sense of Chatham, whose music tends to explore a single tonality, rather than modulating from key to key. And it has its roots in his early work with Young, long an advocate of untempered tuning systems.

Sitting alone behind a table filled with electronic processing equipment, and wearing a black fedora and sunglasses, Chatham began the piece with a short, harsh-toned, sustained trumpet figure, which became the basis of an electronic loop. As the figure was replayed, he added a second, a third, and so on, each a bit more detailed – some with fluttering notes, some either in harmony or clashing with the earlier lines. After a while, he had a hefty drone, with filigree above it, evoking an image of static electricity dancing over a live wire.

He continued the process by adding angular guitar lines, and gentler figures on his various flutes, and over time (the piece ran a bit over half an hour) the drone became an aggressive din – for a time it sounded like uncontrolled feedback – within which rhythmic and, occasionally, melodic patterns emerged. Much of Chatham’s music works this way. Sometimes the results are more attractive: “Crimson Grail,” for 200 guitars (a live recording was released in 2010) is magical. “Pythagorean Dream” is brasher, more of a frontal assault.

So is the trio. As in “Pythagorean Dream,” Chatham looped his trumpet, guitar and flute performances, while Dahl offered heavily distorted bass lines, creating a dense, spiky drone. Only Shea’s drumming remained discreetly defined, and it was magnificent – energetic, varied and richly detailed, almost as if the piece were a concerto for drums and drone.

That isn’t to say there weren’t subtleties. At one point toward the end of the piece, Shea and Dahl stopped playing, leaving the spotlight on a dreamlike shimmer that Chatham created with looped flutes. But that proved to be simply an interlude: Chatham took up his guitar, and Shea and Dahl returned for a slow, insistent crescendo that brought the piece to its conclusion.

Chatham’s music isn’t for everyone. Several audience members walked out during the trio. But those who remained were so taken with the music that when Chatham put down his guitar and tried to get the audience to add its voices (on the syllable “Ahhhh”) to the finale, many stood and clapped instead.

Allan Kozinn is a former music critic and culture writer for The New York Times who lives in Portland. He can be contacted at:

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