The purpose of this study is to investigate the phenomenon of degradation in the accuracy of local sound field synthesis (LSFS) due to the sound scattered by a listener’s head. In conventional sound field synthesis (SFS) methods, the degradation in accuracy due to a listener’s head is negligible, because the degradation are smaller at the low reproducible frequencies than the discretization artifacts of synthesized sound field. As LSFS method synthesizes the sound field only to a narrow extent at higher frequencies which is not considered in the conventional methods, how degraded the reproduction accuracy due to scattered sound in LSFS must be investigated. We conducted simulation experiments, using a rigid sphere for modeling the sound scattered by the head, using two LSFS methods: local wave field synthesis with virtual secondary sources (LWFS-VSS), and the pressure-matching method. The following two points were investigated: (i) The dependency of degradation on the frequency of sound and reproduction position; and (ii) the relationship between the virtual source distance and reproduction accuracy. The results showed that the degradation in the accuracy at the position opposite to the virtual source became larger as the frequency increased. Regarding the distance of the virtual source, when the source was placed near the listener’s head, the reproduction accuracy was significantly low. Specifically, in the case of LWFS-VSS, as the virtual source approached the head, the reproduction accuracy became more degraded compared with the no-scattering condition.
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