Collaboration between Billy Kluver and Robert Rauschenberg.
" The installation is a 36 foot long sculpture made up of three layers of Plexiglas. The front layer is partially mirrorized and behind are two layers of Plexiglas with images of a wooden chair on them. Different lights behind the sheets of Plexiglas vary in intensity based upon the amount of sound in the room and backlight the images so they are visible through the mirror. The sound is divided into four frequency bands, so that a high-pitched voice or sound would trigger a different set of lights from a low-pitched voice or sound; that is, children trigger different lights from adults standing beside them. "