„Once a year at predetermined hours, sirens were once tested on city roofs. For
this test, I used to walk regularly across the fields on the outskirts of town.
The sirens from neighboring cities kilometers away generated a fascinating
spatial resonance, certainly the most spatial acoustic sound space I have
experienced so far."
Air passing through rapidly rotating perforated discs produces a characteristic siren
sound. The instrument, which was built in 1989 and reworked in 2002, is futuristic in
appearance, somewhat resembling an alien or some other figure from a science fiction
film. The siren is 2.40 meters high and 3.50 meters wide and consists of eight discs,
which can be triggered by eight throttle flaps and 16 motors. Wind machine blowing air
into the valve box. The valves distribute the air to the eight hoses.