At NAE, we have various research and experimental facilities to promote research & development activities. We are working on not only our own products but also on the contractual experimental operations to actively support our customers' development activities.
■ Anechoic Room
This is an anechoic room that is highly flexible with variety of possibility by adding a removable sound absorption wedge to the floor to make it a full anechoic room and removing the wedge to make it a semi-anechoic room. It can support every measurement uses, i.e. it enables to conduct the accurate acoustic feature measurement of the acoustic instrument such as speakers in a fully anechoic room and also enables to conduct the sound insulation performance assessment, such as the acoustical contribution analysis and the contribution analysis, by car’s partial transfer pass to place the car into the semi-anechoic room. The microphone for measurement can accurately conduct the measurements at various points, such as measuring the sound power level and measuring the sound pressure level/sound intensity level, by using a full automated microphone traverse system.
In a full anechoic room
In a semi-anechoic room
■ Purpose
- Full Anechoic Room
- Semi-Anechoic Room
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- Measurement of Sound Power Level
- Transfer Pass Analysis of Vehicle
- Various Model Experiments
■Specifications
- Usable dimension:
- 6.2m(D)×4.8m(W)×2.9m(H)
In a full anechoic room - 6.2m(D)×4.8m(W)×3.5m(H)
In a semi-anechoic room
Cut Off Frequency: 160Hz
Measurement frequency range: 160Hz～20kHz Acoustic measurement (the sound radiation characteristics/directional pattern /transfer function etc)
■ Reverberation Room
We have 2 types of reverberation rooms, a large and small one, according to the object and propose of measurements. Using a large reverberation room, it is possible to compare a large sample of construction material using the reverberation method of sound absorbing measurement; furthermore, you can put a vehicle into the chamber to conduct a noise insulation performance test on the body of the car. Using a small reverberation room, you can measure the sound absorption on a small sample of the interior material of a vehicle. It doesn’t matter which microphone rotator system you use, it can automatically measure the balanced data.
IIn addition, the sound source adopts the multi-source to improve the diffuseness respectively. The method of measurement is planning the improvement of the measurement precision to adopt the impulse response method in addition to the usual interrupted noise method. Also, we perform the study for the evaluation of diffuseness of reverberation room itself.
Large Reverberation Room
Small Reverberation Room
■ Purpose
- Measurement of Sound Power Level
- Measurement of Sound Absorption Coefficient by Reverberation Room Method
- The Experiment of Sound Insulation Evaluation of Vehicle
■ Specifications
- Large Reverberation Room
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- Capacity: 140m3
- Usable dimension: 7.4m(D)×4.7m(W)×4.0m(H)
- Sample dimension of sound absorption coefficient by reverberation room method measurement : 8m2
- Frequency range of sound absorption coefficient by reverberation room method measurement : 200Hz～5kHz
- Small Reverberation Room
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- Capacity: 9m3( heptahedron (irregular shape))
- Sample dimension of sound absorption coefficient by reverberation room method measurement : 1m2
- Frequency range of sound absorption coefficient by reverberation room method measurement : 500Hz～5kHz
■ Aperture between Reverberation Room and Anechoic Room
By placing the sample into the space between the reverberation room and anechoic room and using the reverberation room side as a sound source room and the anechoic room as a sound receiving room, we can conduct a measurement for sound transmission loss by measuring the intensity of the sound penetrating the sample (Sound intensity level). We can use the variety of measurement from the measurement of the sound transmission loss of construction material, sash, etc. to evaluate the weak point of the sound insulation by distribution of sound intensity around a surface to attach a sample of a large dimension such as a pressed and cut body of car at the large aperture between the reverberation room and the anechoic room. The sound transmission loss from a small sample is measured at the small aperture between the reverberation room and the anechoic room.
Aperture between large reverberation room and anechoic room
Aperture between Small Reverberation Room and Anechoic Room
■ Purpose
■ Specifications
- Large Reverberation Room
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- Sample size of sound transmission loss measurement : maximum 2.7m(W)×2.3m(H)
- Frequency range of sound transmission loss measurement : 200Hz～5kHz
- Small Reverberation Room
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- Sample size of sound transmission loss measurement : maximum 1.0m(W)×1.0m(H)
- Frequency range of sound transmission loss measurement : 400Hz～5kHz
■ Listening Room
In a listening room, the comparative listening using auralization as a result of various simulations, the sound psychoacoustic evaluation test which uses the listening experiment system and the NES monitor speaker system. Regarding the auralization technology, it is possible to have the reproduction of the sound in a concert hall by using a multi-channel reproduction (14ch) and the "OSS" 2ch sound field reproduction system. Listening by audio corresponds to various formats from 2ch stereo (CD) to multi-channel (DVD-video/DVD-Audio/SACD). Furthermore, it is possible to project a DVD formatted video by using a permanent 100 inches screen.
Listening room
Listening room screen use
■ Normal Incident Absorption Coefficient Measurement System
The normal incident absorption coefficient measurement system (ISO10534-2 complied) uses 2 types of 40mm diameter, 300mm x 300mm acoustic tubes. In these recent years, using the transfer function method (ref.JIS) has become a mainstream way of measurement. It is possible to compute the acoustic feature. You can not only compute the normal incident absorption coefficient and the normal acoustic impedance that are measured commonly but also the characteristic impedance, the propagation constant and the normal incident transmission loss.
Normal Incident Absorption Coefficient Measurement System
■ Specifications
- Measurement frequency range
- 200Hz～5kHz: on measuring sample of 40mm in diameter
- 63Hz～500Hz: on measuring sample of 300mm×300mm
■Measurement Item
■ Acoustical Materials Measurement System for Biot Model Prospect
The experimental equipments for acoustical materials measurement system for Biot model prospect used for the estimation of acoustic absorption / the sound insulation performance of various fixings in the automotive industries. These equipments are utilized for our own research & development activities and for collaborative research from our customers. NAE inspects the actual surveys on both prospect and precision by comparing the predicted acoustic absorption / the sound insulation performance to the actual measurement using the acoustic impedance tube and the reverberation room / anechoic room.
Acoustical Materials Measurement System