Abstract
This paper describes a laboratory study for investigating the contribution of sound quality on annoyance. To measure the annoyance, two kinds of subjective evaluation test were carried out, i.e., one for annoyance and the other for listening interference. Our findings were : (1) contribution of high frequency contents of road traffic noise on annoyance was significant, (2) the contribution of high frequency contents of road traffic noise due to its modification beyond 1kHz by increasing and decreasing its level was equivalent to 3dB (A) even when the levels of the noise were fixed to 70dB (A), and (3) multiple regression models for annoyance in terms of LAeq, roughness and sharpness were constructed and the trade off relationships between the sound quality parameters and LAeq were calculated. The value of trade off of one standard deviation in roughness and sharpness for annoyance were equivalent to 4.3 dB (A) and 0.9dB (A) respectively provided that one standard deviation in LAeq in the model was 6.0 dB (A).
