I caught about an hour’s worth of some very fine improvising at the New York Cultural Center on Sunday afternoon. Musica Elettronica Viva originated in Rome, though most of its members were Americans, and the group became well known for its many appearances in European avant-garde events, as well as for its contribution to the explosion sequence in the ‘Zabrisky Point’ sound track. This four-man performance by Musica Elettronica Viva (New York) was an energetic free-form improvisation with a tight ensemble feeling.

Trombonist Garrett List stuck mostly to atonal melodies and virtuoso riffs, and much of his playing could have passed for fairly far out jazz solos. But he was always extremely sensitive to the rest of the group and seldom took the spotlight for very long at a time.

Gregory Reeve, the percussionist, pulled the group together dynamically, contributing much energy whenever things started to build, but always getting out of the way quickly as soon as an idea played itself out.

Pianist Frederic Rzewski seemed to be calling many of the plays, though he was never at all domineering. He simply has an uncanny knack for running across fresh material which is so appropriate to the moment that the others tend to follow suit. One of his contributions was a soft, oddly harmonized version of ‘A Mighty Fortress Is Our God,’ which was as effective as it was unexpected.

Richard Teitelbaum is extremely facile with his Moog synthesizer, and his electronic sounds always seem to blend with the instruments. He generally stayed in the background, and could not be heard at all in many loud passages. Yet his modest role provided the element which most clearly distinguished the music from that of similar improvising groups.