Quiet rooms are similar to VSAC's, except without a chassis dynamometer. Quiet rooms are typically facilities for taking acoustic measurements around a stationary or idling vehicle.
Noise from components and tangible areas of a vehicle that a consumer will interact with such as handles, switches, door closures and windscreen wipers are measured in quiet rooms.
Due to the measurements being taken, quiet rooms need to be isolated from any other noise sources.
Typically manufactured from acoustic walls and ceilings, the addition of anechoic wedges ensures minimal transmission of sound from other areas of the facility entering the test chamber. Background noise typically ≤ 20dB(A).
Modal analysis facilities are used to measure the resonance and tone of bodywork panels on a vehicle. Panels are struck with differing degrees of force and the resulting resonance measured. This type of testing is used to ensure panels do not excessively vibrate, causing unwanted noise. Panels which are found to have a high degree of resonance can be treated with additional supports and strengthening to overcome the problem.
Like listening rooms, IAC modal analysis laboratories are constructed from Moduline™ acoustic panels to isolate external noise from the facility. The room is then treated with IAC Varitone™ panels to tune the space for an optimum amount of absorption.