Acoustic Anechoic Room, large

The large 65 m2 anechoic room is among the most used rooms in the laboratory.
Many acoustical measurements necessitate the use of an anechoic room, e.g. measurements of loudspeakers and microphones. The room is also used for listening experiments.

The walls, ceiling and floor are all covered with sound absorbing wedges so that reflections are avoided. Between the wedges inside the room there is 6.2 m x 5.0 m x 5.8 m, lower cut off frequency approximately 65 Hz.

The room is a double-box construction made of concrete. The inner box (9.1m x 7.9m x 8.7m) is placed on a rubber suspension in order to insulate the room against noise and vibrations from the surroundings. Even when the air-conditioning is on there is no audible background noise in the room.