ITS has marketed an anechoic lining for a room dedicated to the verification and testing of electro-acoustic equipment for audiovisual, in the Paris region (France).

The selection of this anechoic lining was made taking into account various requirements :

  • acoustic performance (a sound absorption coefficient of 100% was sought at frequencies as low as 100 Hz)
  • the limited space available (the thickness of the anechoic lining correspondingly reduces the space available inside the room)
  • the reaction to fire of the components

The broadband compact absorbers marketed by ITS have proven to be the best possible choice, such a constructive system satisfying all the requirements of the project, with a multilayer acoustic structure specially developed for such applications (from the rear to the front) :

  • a dissipative material (mineral wool, polyester wool or foam)
  • a metal membrane: combined with the layer located at the back, it constitutes a resonator, allowing acoustic absorption at low frequency
  • a dissipative material (mineral wool, polyester wool or foam): allowing acoustic absorption at medium and high frequency
  • a perforated protection

The assembly is non-flammable (or even: non-combustible in case of an even more demanding selection of some components with regard to the criterion of reaction to fire).

BCA (Broadband Compact Absorber)

As their name suggests, these absorbers are :

  • compact (roughly : only a quarter of the thickness that would be required - with equal performance - for conventional absorbing wedges)
  • broadband efficient :
    • a sound absorption coefficient of 100% is obtained from a low (cut-off) frequency - variable depending on the composition of the lining and depending on its thickness, generally 0.250 m or 0.350 m - up to the highest frequencies of interest (20 kHz for the human ear)
    • a far from negligible sound absorption coefficient is obtained below the cut-off frequency

With a sophisticated design, a configurable performance, a modular appearance and a meticulous manufacturing, the broadband compact absorbers marketed by ITS constitute the ideal covering (walls, ceiling, even: floor) for many acoustic test rooms :

  • semi-anechoic and anechoic room (the floor is then also covered with absorbers) with, in some cases, a concept allowing conversion from one configuration to another, for what concerns anechoïcity
  • aero-acoustic wind tunnels (experiment room, aeraulic circuit channels e.g. elbows)
  • test bench of all kinds

Electroacoustic equipment for the audiovisual sector is not the only hardware concerned by tests and verifications requiring, for a measurement room, an anechoic lining such as that constituted by the compact broadband absorbers marketed by ITS, the applications being in reality very diverse, in relation to the sectors of activity for which acoustic measurements (sound characterization) e.g. in a context of Research and Development - R & D - make sense (in companies and also in universities and engineering schools) :

  • transport (automotive, rail, aeronautics and space)
  • household equipment
  • construction

Of course, the accesses constitute singularities requiring the development of contextualized solutions for the installation of an anechoic lining, a fortiori when the opening of a door is planned towards inside of the anechoic room, as in the case of the project to which this article relates.

The experience acquired over decades, on the occasion of similar projects, makes the difference when it comes to offering the best compromise between performance and price for this, as for the management of all interfaces with equipment (lighting system - which could be marketed by ITS, with lamps then 100% integrated into the anechoic lining -, ventilation / air conditioning network, electrical accessories and for measurement, various supports and easements).

There is no doubt that the anechoic lining marketed by ITS as part of this project (the end customer being a large French group with very diversified activities) will satisfy users of a room dedicated to the verification and testing of electro-acoustic equipment in the audiovisual sector.

Testing rooms acoustics end faq