Up until a few years ago, R&D laboratory interests were centered on dynamic vehicle behavior. Issues such as drivability, security or fuel consumption are now generously optimized. More and more focus is placed on noise and vibrations. Minimum noise is not the only issue anymore: nowadays, noise emitted should be pleasant. A major parameter contributing to the general comfort and security felt by vehicle passengers is cabin sound. Cabin sound is used as an indicator for the general quality feeling given by a vehicle. As a result, investments have been made by car manufacturers and component suppliers to tackle and improve, cabin noise. Studies are often required to validate numerical simulations or to provide input data to models. Dealing with two case studies, we can describe how such measurements can be used, and what benefits can be obtained from adopting new test procedures and equipment. Some of the most studied sources are from engines and tires. Depending on driving conditions, other types of source may appear: a rough road surface may induce noise in the suspension system. In some situations, noise may also be generated by the steering system driving at high speed or with windows open will generate high aerodynamic sound. In addition, heavy braking sessions may create brake squeal that may be enhanced in the case of worn brakes. But sound and vibration should not only be controlled at their generation stage, their propagation should also be understood and reduced. Looking at noise transmitted through the air, studies concentrate on the door sealing characteristics on the body panel sound transmission.
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