Sums & Differences (1978)

The basis of this “sound/image construct,” recorded in real time, are three black-and-white still images: a keyboard, a flute, and an African drum. These motifs are altered through digitalization, solarization, and interframe switching. As they alternate, the images are accompanied acoustically by simple tonal routines of the instruments shown – little sequences of sound on the keyboard, some drum beats, a brief trill of the flute. The solarization effect of the images changes with the sounds. The work intensifies as it progresses, and images and sounds succeed one another ever more rapidly until a melody of the three instruments emerges. The frequency of the video images continues to increase, with the result that the images pulsate ever more quickly until they gradually overlay one another, producing a cinematographic effect through interferences. Parallel to this, the audio frequency of the melody rises until fundamental tones form, lasting several seconds.