Non-narrative film montage--the jumbling of brief sequences of images--has the purpose of "keeping one on one's toes," filmmaker Warren Sonbert told 50 people at the Carpenter Center last night.

Sonbert, a leading U.S. avant-garde director, said his theory of montage is based on "positing" one connotation of an image, "and then, as the work unravels, you take that away." In his film Honor and Obey, for example, police officers are first presented in violent roles, but in later scenes have peaceful conversations.

"No one thing is triumphant," Sonbert said of the fragmentary elements of montage. Instead, a film's aim is to keep a "constant balance" between its scenes so that a marriage scene may be followed by a funeral. The audience may laugh when the image of a child appears on the screen, but the "laughter is a little bit qualified" by a following image of an ambulance or burning car, Sonbert said.

The avant-grade director said editing is crucial to determining the impact of images.

"The duration [of the image] is of strategic importance," he said, adding, "The idea of keeping one on one's toes is very, very important."

To gather footage for his montage. Sonbert said he often looks for parades, demonstrations and other events. such as military exercises and car accidents.

"I travel a lot," he said. "You can scoop up disasters sooner or later." He said his films are usually shot over a period of about two years and edited in one to three months.

Sonbert appeared at the screening of four of his films as part of "Avant-Garde Voices." a two-night series sponsored by the Harvard Film Archive. Last night's screening featured two recent films, Honor and Obey (1988) and The Cup and the Lip (1986).

Both films are works in film montage constructed of scenes shot around the world. The third film, Hall of Mirrors, is a combination of sequences from a 1948 motion picture with two scenes shot in New York. Hall of Mirrors and the fourth film shown last night were made while Sonbert was a student.