Hybrid active noise barrier with sound masking (Experiment for verifying the noise attenuation performance in an office room and evaluation of maskers by listening experiments)

A hybrid active noise barrier (ANB) integrating sound masking techniques, which aims to abate the noise problem and improve the speech privacy in open plan offices, has been proposed in the previous work. This ANB exploits a hybrid active noise control (ANC) system with sound masking techniques to reduce and mask the target sound simultaneously, so less masker power is needed to achieve the same masking performance with the conventional sound masking techniques. In the previous work, the effectiveness of the ANB has been verified by computer simulations and by experiments in an anechoic chamber. In this paper, an experiment is conducted to verify the noise attenuation performance of the ANB in the sound field of a real office room. The influence of background noise on the noise attenuation performance of the ANB is also investigated in the experiment. Moreover, in order to select an appropriate masker for the sound masking part of the control system, several types of maskers are compared and investigated by listening experiments in this paper.