When one is looking to develop a testing room for measurement and experiments involving instrumentation in acoustics, ITS offers a wide range of anechoic chambers for many applications:
- anechoic rooms or of semi-anechoic rooms, properly speaking
- aero-acoustic (aerodynamic) wind tunnels
ITS offers powerful solutions at a reasonable cost in response to all needs in the matter of acoustic measurement rooms that anechoic chambers are (construction or retrofit) by the means of equipment whose quality of design and of execution meets the highest requirement level in this area in the context of R & D for acoustic comfort.
Features of anechoic chambers marketed by ITS
The anechoic chambers marketed by ITS allow, for high-quality measurements/instrumentation in acoustics, to obtain, across the entire frequency range of interest:
- free field conditions (when applicable: on a reflecting floor) meeting the requirements of standard 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. This is, of course, a fundamental feature of such a testing facility, designed to eliminate unwanted acoustic reflections from the partitions forming its physical boundaries
- excellent airborne and structure-borne noise insulation - a second essential function for noise protection:
- of the interior of the anechoic chamber when a sufficiently low background noise level is required for measurement involving quiet equipment (e.g. telephones, electrical appliances, car doors during closing, automotive electrical components such as fans, switches, and small motors like those for window lifts) or even silent equipement (e.g. hearing protection devices), even more if external noise or ground vibration levels are high e.g. in industrial settings (in a location possibly near or even amidst - as with "end-of-line" testing facilities - of production areas that are potentially noisy or généerating vibrations, such as those containing machinery like presses)
- of the exterior of the anechoic chamber when the equipment under test is itself very noisy (e.g. loudspeakers, sirens, engines, vehicles), even more if other activities in the installation area require concentration (e.g. design work, Research and Development - R&D -)
Characteristics of anechoic chambers marketed by ITS
The anechoic chambers marketed by ITS are usually made of modular elements whith a geometry defined for each project, covered by a cloth (eventually: with a painted metallic perforated protection) with an insulation (filling) made of mineral fiber or of foam or of polyester fiber (walls, roof and if applicable: floor) that equip also (by the means of mobile sets) the places of acoustic doors allowing to access to the measurement room and the places of acoustic windows allowing the visibility from a control room. Some of those elements may have a sound absorption coefficient for normal incidence αo close from 100 % from 50 Hz (higher performance related to a lower cut off frequency can be obtained by the means of special constructions).
Regarding products and construction systems proposed by ITS their performance is measured in laboratory according to current standards:
- their sound absorption coefficient according to the standards NF EN ISO 354 Acoustics - Measurement of sound absorption in a reverberation room and NF EN ISO 11654 Sound absorbers for use in buildings - Rating of sound absorption
- their sound absorption coefficient for normal incidence according to the standard NF EN ISO 10534-1 Acoustics - Determination of sound absorption coefficient and impedance in impedance tubes - Part 1: Method using standing wave ratio
The absorbing treatment for anechoic chambers offered by ITS are a choice acoustic lining as soon as it comes to quantify (in a laboratory) the noise emissions of noisy equiment or to develop equipments sufficiently silenced or having a particular sound design, that make use of specific testing rooms as for the automotive sector (anechoic rroms are called anechoid rooms sometimes).
A guarantee of acoustic performance on site is issued for each installation of anechoic chambers. ITS is marketing anechoic chambers for research & development sound and noise levels measurements in free field conditions for which quality depends on addressing user needs beyond purely acoustic requirements (such as anechoicity and sound insulation, as mentioned earlier):
- integration into the installation site and dimensional optimization
- management of access for personnel and equipment under test
- accommodation of ancillary equipment (lighting, utility routing)
The success of an anechoic chamber project hinges on meticulous attention to every detail. The anechoic chambers proposed by ITS can be delivered as a kit ready to assemble with assembly instructions or be installed turnkey. They can allways be disinstalled for a reinstallation in a different place.This is a major asset in a world where the relocation of industrial sub-assemblies is frequent.
Standardized and tailor made anechoic chambers marketed by ITS
Needs expressed by various clients regarding anechoic chambers, analysed as being with some recurrence, led to the market launch of a standardized range (in case of enclosed rooms to limit airborne sound transmission, with a vibration-decoupled floor, this latter with sound-absorbing lining for full anechoicity):
Summary of dimensions for standard anechoic chambers marketed by ITS
| Size | Inner length (m) | Inner width (m) | Inner height (m) | Volume of acoutic free field for a cut off frequency of 100 Hz (1/3 octave) |
| S | 2.9 | 2.4 | 2.1 | Parallelepipedic, with dimensions 1.85 * 1.45 * 0.95 m3 |
| M | 5.1 | 4.1 | 2.6 | Spherical, center on anechoic chamber center, with radius 1.3 m |
| L | 5.1 | 4.1 | 3.6 | Spherical, center on anechoic chamber center, with radius 1.5 m |
Such standardized anechoic chambers offer numerous advantages:
- design and engineering work of all kind already completed (shorter lead times and lower costs)
- verification of intrinsic acoustic performance already carried out (saving both time and money)
Of course, it would be illusory to assume that all needs - whether for industrial settings, engineering schools, or universities - can be met by just these three models and along times, one can observe that many projects involve specific requirements that necessitate the design of custom anechoic chambers, distinct from standardized models:
- possibly in terms of dimensions e.g. for the necessary addpatation to limited footprint
- possibly in terms of acoustic characteristics (e.g. with a reflective floor for semi-anechoic chambers, with an extended frequency range, or with enhanced wall insulation)
- possibly in terms of access e.g. large doors for vehicles
- possibly in terms of their connex equipment
ITS therefore also offers custom-built anechoic chambers - based on the Client's technical specifications where available - for diverse applications across a wide range of business sectors, of which a common trait is a need for optimized design, quality construction, controlled timelines and costs, and guaranteed on-site performance, all made possible by extensive experience in the field.
absorbing lining based on wedges |
 absorbing lining based on compact absorbers |
The anechoic chambers offered by ITS are robust constructions with quality finishes ensuring a high durability. They are notably used in order to equip acoustics R&D laboratories (anechoic rooms and aero-acoustic wind tunnels in all fields of activity), for universities,engineering schools, research institutions. |
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Absorbing lining for acoustic measurement rooms |
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See the frequently asked questions related to this equipment |
Acoustic laboratory, acoustic measurement room, acoustic testing room, anechoic chamber, anechoic room, dead room: all equipment that one can source thanks to Isolation Technologie Services (ITS).
Note: ITS also offers acoustical insulators and soundproofing products (materials and construction systems) for acoustic measurement rooms (building envelope) like anechoic chambers or aero-acoustic wind tunnels.
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Metallic acoustic door set |
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Metallic acoustic insulation panel without any absorbing face |
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Metallic acoustic window set |