THE EFFECT OF HORIZONTAL ORIENTATION OF SOUND SOURCE ON ANNOYANCE: EXPERIMENT AND MODELING

It has been observed that the direction of the sound source has considerable effect on annoyance, which is called spatial effect. However, the existing investigation focused rarely on such an effect. Therefore, a laboratory study is conducted to investigate the spatial effect of annoyance for horizontally incident noise. First, three typical acoustic signals are generated, which are three white noise with different sound pressure level (SPL), four narrowband sound with different center frequency and four amplitude-modulated sounds with different modulation frequency. Combined with head related transfer function (HRTF) data, sound in different azimuth angles can be obtained by convolution. Then, the subjective experiment was conducted. Subjects marked the annoyance score for each stimulus played back by the headphones. The results show the consistent variations of the annoyance with the azimuth angle of the three kinds of sounds. For each sound, in different angles, the gradients are different. The annoyance1 of three kinds of sounds reach a maximum at around directly left and right about 2 points on the basis of a 0~10 scale. The annoyance reaches the maximum when the sound source is on the left or the right hemifield, and the minimum at the rear. The annoyance of each kind of sound shows the left/right symmetry, but front/back asymmetry.The analysis above provides a theoretical basis for the mechanism of spatial annoyance and the spatial correction model of annoyance. Based on binaural acoustic parameters, a liner regression model is established to predict the annoyance of spatial noises. And based on the characteristics of the annoyance results, trigonometric regression models are established for three kinds of sounds.