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A fully analytical method for the evaluation of noise reduction in a vehicle interior furnished with layered acoustic trim is presented. The method combines calculation of trim Transmission Loss (TL) and Absorption Coefficient with a Statistical Energy Analysis (SEA) calculation of trimmed panel Noise Reduction (NR). This allows for the evaluation of the trim package performance in real operating conditions and ranking of the different air-borne and structure-borne transmission paths.

Statistical Energy Analysis (SEA) is used to predict wide-bandwidth noise and vibration. That prediction may rely on parameters derived from theory or from test, which essentially means that there are two distinct approaches, analytical SEA and test-based SEA. The latter is the focus of this paper. Both theory and practice are reviewed, so that the current status of the method can be established. This review also provides some insight on what information can be extracted from the experiment, how the measurements must be conducted and how the results must be interpreted. Another important aspect of test-based SEA is its interaction with the more widely used analytical SEA method. It is demonstrated that both methods are complementary and that the analytical and test-based parameters can either be compared or mixed in a “hybrid” SEA,model. Benefits of the combined use of the methods are discussed. The discussions are supported by results obtained for automotive applications.

Modern PCs are built on multimedia processors designed to handle computer-generated three-dimensional image as well as stereo sound in real time. In this paper we report on research that takes advantage of these recent capabilities. A prototyping system designed to provide an enhanced visual and auditory experience of the interior noise performance of a vehicle was developed. The system can be used for the subjective evaluation of modifications to the sound package of an existing vehicle. The latest virtual reality technology is combined with digital sound processing and Statistical Energy Analysis simulation to provide the user with a unique visual and auditory experience.