douglas irving repetto

Slowscan Soundwave (II)
(sound-reactive mylar)

very long mylar strips,
string, motors,
custom electronics, computer

I was asked to do an installation as part of the Re:NEW Frontiers in Creativity Symposium celebrating Columbia University's 250th anniversary. I wanted to do a large version of Slowscan Soundwave but the immense size of the space (Low Library) made that impractical. So I decided to rotate the idea 90 degrees to create a similar, but much larger scale and more immediate work.

Slowscan Soundwave (II) consists of ten giant strips of transparent mylar suspended across the four sides of the rotunda in Low Library. They overlap to form a radial pattern. Each strip is attached, via a string, to one of two small motors. The motors in turn are attached to control circuitry and a computer that is listening to the ambient sound in the space. As the sound changes the computer changes the speeds of the motors. One motor's speed is tied to the volume of the sound in the space: as the volume rises, the speed of the motor increases. The other motor's speed is tied to the frequencies present in the sound: as the predominant frequency rises, the speed of the motor increases.

As the motors turn they gently tug on the strips of mylar, which introduces subtle ripples along their lengths. Because the tugging is related to the ambient sounds in the space, the ripples in the mylar are like a reflection of those sounds. The system reacts very quickly; for example, if it is quiet there will be no movement, but if you clap you will see a sudden ripple in the mylar strips.

Since the mylar strips are transparent and were hung about 60 feet above the audience, their effect was very subtle. At times it was difficult to even see them, while at others they would catch a bit of ambient light and then shimmer gently, causing water-like refractions and reflections. The effect was a bit like shouting into a pool of still water: subtle but definite reactions to changes in ambient air pressure.

A gallery of images from the installation