Human response to sonic booms and rattle heard indoors

Human response to sonic booms heard indoors is affected by the generation of contact-induced rattle noise. The effect of sonic boom-induced rattle noise was studied in a series of psychoacoustics tests. In order to remove the effects of loudness, sounds were equalized to the same perceived level (PL) in each test. Stimuli were divided into three categories and presented in three different studies: isolated rattles at the same calculated PL, sonic booms combined with rattles at the same calculated PL, and sonic booms combined with rattles at three different PL. The sonic booms, both measured and synthesized, were filtered to simulate presentation inside structures with different transmission and reverberation properties. The rattle sounds due to sonic booms or mechanical loading were recorded in a residential home. Subjects listened to sounds over headphones and were asked to judge the level of annoyance of other factors, depending on the test. Annoyance to different rattles is shown to vary, and the combination of sonic booms and rattles can be more annoying than the sonic boom alone. These results show that the PL metric does not fully represent human annoyance to the selected indoor sonic boom and rattle sounds.