Alex Hay
«Grass Field»

For Grass Field Alex Hay wanted to pick up body sounds: brain waves, muscle activity and eye movements. Pete Kaminsky, Fred Waldhauer and Cecil Coker built a battery-driven differential amplifier which had a peak gain of 80 db at low frequencies from 112 Hz to 10 Hz. The whole unit, batteries and all fit into a 1" x 3" x 5" box, no mean feat to do this in 1966. The signal from the differential amplifier was fed into a voltage-controlled oscillator, then to a transmitter, which sent the sound to the speakers. Electrodes were placed on Hay's head and body and all the equipment was attached to a plastic plate fastened on Hay's back. These body sounds were heard through the speakers as Hay carefully laid out 64 numbered pieces of cloth. Here Hay is sitting in front of a television camera and the image of his face is projected on the screen behind him as Robert Rauschenberg picks up numbered cloths.