Concerts by two of the boldest innovators in today's 'new music'; Proceed Accordingly Solo recital by David Van Tieghem.; Symphony No. 1 -- Tonal Plexus. Concert by Glenn Branca.

The Performing Garage, usually the place to go for experimental theater, took a musical turn for part of the summer season. Concerts were given by David Van Tieghem and Glenn Branca, two of the boldest innovators in today's "new music" world.

David Van Tieghem began his musical life as a child, playing pots and pans in his parents' kitchen. Later he became a professional percussionist, but he still loves those pots and pans. His current work ranges from conventional drumming to hubcap solos, rhythms coaxed from children's toys, and cadenzas for masking tape.

At the Performing Garage, he presented "Proceed Accordingly," an expanded version of a piece that has been heard lately at Carnegie Hall and at least one New York disco. The show begins as soon as you enter the theater and see Van Tieghem's paraphernalia -- a huge collection of objects, large and small, whose only common property is the ability to be hit, struck, or tapped.

The most important prop is a microphone, which gathers the subtlest vibrations and amplifies them into major sonic occurrences. In the tradition of the John Cage school, which suggests that any sound may be considered as music, Van Tieghem moves among his gear with drumsticks in hand, building an improvised series of themes, rhythms, riffs, and even an occasional tune. In the background runs a tape of prerecorded music, lending support and counterpoint.

When presented in abbreviated form, Van Tieghem's work can seem like a mere bag of tricks, a string of events with no structure to hold them together. In his hour-long show at the Garage, he laid this criticism to rest: Though definitely linear in form, "Proceed Accordingly" seemed under tight control every moment -- not rigorously constructed, perhaps, but clearly built on its own inner logic.

And that logic was followed to extreme conclusions. After a while, the sound became increasingly rarefied, and eventually disappeared altogether, replaced by flashes and swirls of light -- from various sources in keeping with the spirit of the evening, such as Star Wars "light sabers." Finally even these objects were dispensed with, leaving Van Tieghem to do a crazily robotic dance, an extension of his whimsy into wholly visual terms. It's a fine coup de theatre, and a fine dance. Seen several times within a few weeks, it never fails to look surprising.

Van Tieghem is a trickster, but he is also a solid professional who has played with such ensembles as the Steve Reich Musicians and the Love of Life Orchestra. His work is engaging to the ear, invigorating to the eye, and -- equally important -- rousingly entertaining, even funny much of the time. True, he isn't exactly original when he pokes a microphone toward the face of his assistant (Darcy Lee) and regales us with the sound of Rice Krispies being munched. But who can resist such a splendiferous climax, even if composer John Cage did invent this particular genre? Snap, crackle, pop!

The following week Glenn Branca took over the Performing Garage with his Symphony No. 1, an hour-long work of astonishing force. Played by a 15-member ensemble, with guitars and drums the most prominent instruments, it reached a level of barely contained energy that must be without parallel on the current music scene.

Branca's approach to the guitar is -- unusual. Melody and harmony are the last things on his mind. Rather, he seeks a kind of fabulously creative noise in which outlandish textures and sheer volume replace most other musical qualities. The result has much in common with rock, but moves beyond the repetitive structure of rock into a restlessly shifting terrain all its own.

Branca's first symphony carries the subtitle "Tonal Plexus." The musicians play a variety of instruments, including brass and keyboard, all heavily amplified. The first movement begins with a single note, softly played, which grows into a chord, loudly played. The second movement begins in a more lively fashion, with a spunky rhythmic pattern, and steadily builds in volume and power , like the preceding section.

The work reaches its thunderous climax in the third movement, which is basically similar to an explosively exciting piece Branca has played elsewhere as "The Ascension."

The last movement wraps up the piece with a more rocklike beat, laid down by percussionists hitting metal oildrums with large sticks, joined by several guitars and eventually the return of the brass instruments. Like the preceding sections, it is a brave and utterly individualistic chunk of music, sticking to its own strange guns in all respects.

Rarely does music make such a direct physical assault on its audience. This may be a minus for many potential listeners. Yet there is an astonishing immediacy here, an intensity and purity of purpose, that are to be respected as much as Branca's unorthodox musical formulations.

In a recent Soho News interview, he claimed that he barely knows how to play guitar in the usual way. For anyone who has heard him in a more conventional setting -- such as a recent show where he accompanied folksinger Ned Sublette -- this is hard to believe literally. Still, it illustrates Branca's iconoclasm and his wish to function on entirely innovative terms. While his work may be too radical to appeal to a truly wide audience, it deserves to be heard and considered by any lis tener with an open mind and an exploratory ear.