Technique: sine waves, speakers, amplifiers, cd players
pedestrian underpass of the Triemli tram and bus station
September 15–November 15, 2007
Four glass display cases in the pedestrian underpass beneath the Triemli bus and tram staion in Zürich provided the inspiration for this installation. The underpass itself is more of a non-place, a corridor people use to cross below the busy intersection above on their way to Triemli hospital.
I wanted to find a way of enhancing the spatial qualities of this rather drab passageway with sound coming from the display cases. While doing initial sound tests I noticed that the wheels from the departing trams above emitted a whining, metallic tone of approximately 440 hz. While generating this same frequency sine waves from the display cases a subtle beating occurred, but only when the trams were leaving the station.
I decided to augment this sporadic frequency interference with the trams by having each display case emit a one hz different frequency of sine wave, starting with 440 hz in display case number one, then 441 hz in display case number two, 442 hz in display case nubmer three and 443 hz in display case number four. In this way the four cases created subtle beating between themselves.
As the sine waves were emitted from within the closed display cases it became impossible, when walking through the underpass, to locate where the sound was coming from. I purposely had the volume level of the display cases at a moderate level, trying not to impinge on the natural underpass sound environment but to find a balance where it sometimes became difficult to know if sounds were coming from the installation or the underpass itself.
The installation ran everyday for three months, from eight in the morning to eight at night.