A rating scale experiment on loudness, noisiness and annoyance of environmental sounds

Abstract How people judge loudness, noisiness and annoyance of sounds was investigated by using a variety of environmental sounds. Fifty male and female subjects, aged from 18 to 60 years, heard 59 environmental sounds as well as seven kinds of white noise and judged their loudness, noisiness and annoyance on rating scales. Average scores on the three concepts given to the steady white noises are approximately in linear proportion to the level of the noise, with high correlation coefficients. The relationships were used to convert the scores given to the sounds to the levels of white noise which would have the same scores and can be regarded as points of subjective equality ( PSE 's) of the sounds. It is found that the PSE thus obtained concerning loudness is best correlated among the three with Perceived Level and that concerning annoyance is least correlated with the level. Scattergrams of PSE 's between the three concepts plotted against each other showed considerably high correlations. They are more correlated when sounds such as music, church bell, birds, etc., being on average judged pleasant or neutral, are excluded. This suggests that the human responses concerning those three concepts of auditory sensation and/or perception are mutually correlated. Lower correlation between loudness and annoyance, however, suggests sounds heard as equally loud could be differently annoying. More detailed analysis of the results showed that the judgement of loudness was not independent of noisiness and/or annoyance of the sound.