The design of today's car audio components has to meet high quality expectations with ever decreasing development cost. Predictive methods for the performance of sound systems in view of the optimal locations of loudspeakers in a car can help to overcome this challenge. This paper describes a number of sound field simulation tools to model the acoustic and vibro-acoustic aspects that come into play when transducers are mounted into small cavities such as passenger compartment and door cavities. Examples are shown how FEM software can predict the acoustic modes of passenger cavities and door cavities. Automatic volume meshers are key to the success of the Acoustic FEM solutions. Vibro-acoustic effects, such as speaker membrane vibrations coupled with door cavity acoustic pressure and vibrations on the door trim can be taken into account using Coupled Structural&Acoustic FEM & BEM formulations. Also Fast Multipole BEM is used to boost the realistic frequency range up to 5000Hz and higher. For the very High-frequency modeling (above 5000Hz) beam tracing algorithms based on principles of ray acoustics can be deployed to synthesize Binaural Impulse Responses and deriving IACC-index maps. Aspects of absorbent material properties (complex acoustic impedance) and speaker characterization (velocities) are discussed.
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