Experimental study of the effect of horizontal orientation of sound source on annoyance

A laboratory study of horizontal spatial effect is conducted to study the change and influence factors of annoyance on horizontal position of the source. Three typical acoustic signals in different azimuth angles can be obtained by filtering with the head related transfer function (HRTF). Then, the annoyance scores for each stimulus are marked and horizontal spatial distribution characteristics of annoyance are obtained. At last, correlation and regression analysis are performed based on the binaural acoustic parameters and annoyance results. The results show the consistent variations of the annoyance with azimuth angles of the three kinds of sounds. The range of annoyance caused by the azimuth is about −1~2 points on an 11-point scale. Annoyance is the lowest when the sound source is directly behind, and the highest when it is on the left and right. It is found that the relative binaural loudness or the binaural loudness difference has a significant impact on annoyance of three kinds of sounds, the relative binaural cross-correlation coefficient has a significant impact on wide-band sounds but not on narrow-band sounds, and the type of parameters influencing the spatial effect is related to the frequency distribution of the observed signal. The main factors influencing the spatial effect are related to the overall perception of sound and also the differences between the ears.