These days loudspeaker systems in vehicles are gaining more and more of importance. Usually quite a few speakers are installed and driven in combination in order to obtain a convincing sound environment for the occupants/customers. Sometimes even a 3D sound experience shall be reached, where up to 20 loudspeakers might become necessary. No doubt that such a number of speakers and their proper placement in the car cabin is a rather challenging task, leading to extensive measurements in different cabin environments.In the current contribution, it is suggested to simulate the scenario by means of specially combined computer models. These allow not only a rather economic possibility to investigate different changes/variants without expensive new setups but also an additional gain of knowledge.For the numerical representation of the loudspeaker system a multiphysics approach is needed, namely physical aspects of electromagnetics, structural dynamics, and acoustics have to be considered and combined. Doing so, the different fields might be accounted for by models obeying different levels of detail, where the spectrum might reach from simple 1D approaches to highly detailed 3D models. In view of this, different methodologies such as the finite element method, the boundary element method or energy based formulations need to be coupled. In the current contribution a methodology for the numerical design of loudspeaker systems is developed and discussed by means of representative examples.