prof. Monika Rychtáriková
Have you ever wondered where acoustic measurements are made, and how do they look and sound?
The building of the acoustic laboratory at KU Leuven is built as a room in room system and resting on the metal springs. The whole laboratory consists of several rooms: reverberant room, anechoic room and transmission suite. Let’s have a look inside.
The transmission suite
The transmission suite consist of four rooms and is completely isolated form the outdoor environment in order to measure sound insolation of walls or floors.
Transmission rooms are not only isolated from other environment by double structure — room in the room structure – but the whole laboratory is placed on metal springs which are isolating the laboratory also from vibrations.
Reverberant room is called also diffuse field. Diffuse field because there are no parallel walls, there’s no absorption and the sound is nicely diffused by the structure of the room. It’s a special, standardised which is used for sound absorption measurement.
An anechoic room
Anechoic room is also called free-field. „Free-field” it’s because there are no sound reflections like in a free field. You can see the pyramids on the walls. They have high absorption coefficient and they have also certain depth to absorb also low frequencies. So in fact this room is simulating situation outdoors. It’s like if we were in a grass field and there would be no background noise from the traffic. If we would hear here something it’s our heartbeat or our organs but there is absolutely no sound.
Anechoic room is used for determination of acoustical properties of loudspeakers, for example, for measurements of loudspeaker directivity. This room is also used for determination of the diffusion coefficient.