When a high-tech company considers a testing facility for its R & D activities in acoustics, contact is made with ITS to find out what can be offered in terms of design and construction of a test room, among the range of technologies offered by the company based near Lyon (France), being often the very best of them.

This was recently the case for a world-renowned electro-acoustic company for a project in which, in a very wide range of frequencies, there was a need for both a low level of background noise and acoustic propagation conditions close to the free field, as is necessary for acoustic metrology relating to amplification systems and loudspeakers.

ITS participated in an anechoic chamber project close to Paris (France, Ile de France region).

Despite significant site constraints related to the space available for the test facility which is limited (due to location in tight spaces), the proposed measurement room will have high-end acoustic performance.

A very low level of background noise will be made possible inside the anechoic chamber by the use of an envelope with partitions with very high sound attenuation (“box in the box” concept), with a floor on an antivibration suspension allowing efficient filtering of frequencies as low as 30 Hz.

The anechoicity of the room will be achieved by the use of a multi-layer absorbent lining with integrated resonator, which is distinguished by the fact that it is effective over a wide frequency band (100 Hz-10 kHz) whereas compact, i.e. of a thickness several times lower than those of conventional wedges (the installation of which would have compromised the provision of sufficient useful volume inside the chamber). It will meet the criterion of NF EN ISO 3745 Acoustics. Determination of sound power levels and sound energy levels of noise sources using sound pressure. Precision methods for anechoic rooms and hemi-anechoic rooms.

As is often required for a testing facility to account for the possibility of a move and relocation, this anechoic chamber will be completely removable. It will, undoubtedly, enable other acousticians to do (under optimum conditions, and for a long time) their work i.e. to develop and perfect music broadcasting equipment, for the delight of our ears.