The pass-by noise is a specific domain which has to be discussed in the context of NVH. It is necessary for the homologation of every vehicle. In fact of weather conditions etc. there is an effort to transfer the pass-by noise measurement onto an acoustic roller test bench. Therefore an acoustic chamber in the size of the ISO track is discussed in the standards. Those chambers are very expensive and often not possible because of the infrastructure. The anechoic chamber at the IPEK - Institute of Product Engineering at KIT includes a four wheel roller test bench and is not approving the ISO 362 track dimensions. At the Internoise 2011 some measurements where shown, discussing the acoustical damping of the measurements of the different positioned microphones. The result, calculated by the law of distance, was an inhomogeneous allocation. In this contribution pass-by measurement results in a small anechoic chamber with a point source are discussed. With it the acoustical damping of the chamber and the calculation of the microphone position were validated. So the base is set for the next steps to develop an idle adaptable measurement setup for small acoustic chambers.
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