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In a recent paper [Acta Acustica united with Acustica 93 (2007) 73―83] [1], an experimental noise annoyance meter was proposed for estimating acceptable noise levels, L Aeq7 . In this experiment, the subjects were able to relate the value of L AeqT to the differences between the seven-point annoyance scale scores displayed. Therefore, they directly gave the value of L AeqT for their acceptable threshold. This study investigated whether each acceptable L Ae q T level can be predicted from the annoyance and noise sensitivity. First, multiple regression models for each outdoor noise source were constructed to predict the annoyance from L Ae q T and the noise sensitivity based on the data collected in and around the city of Nagano. The regression models were used to determine whether each outdoor noise was over or under the acceptable threshold, which was defined as the midpoint between the scores "a little annoying" and "somewhat annoying." The correlation between the experimental results using a separate sample of residents from other prefectural capital cities in Japan and the predictions by the regression models was 0.703. Also, the discriminant models were used to classify cases by their values of a categorical dependent, where correlation with the proposed models was 0.837, indicating that the discriminant models are valid.

The noise level and the effective noise level used for noise evaluation are physical indices and generally are not understood. It is believed that the understanding of such physical indices can be enhanced if one can realize a sound level meter which can display directly the relationship of the psychological effect by the noise with the measured decibel scale. From this point of view, this paper first evaluates in a laboratory experiment the relationship between the hue level expressing the psychological effect and the effective sound level. According to the obtained noiserating scale, the five-hue scale, “red, purple, yellow, green, blue” and the effective noise level correlate well. Next, a new sound level meter including the obtained noise-rating scale (to be called the hue sound level meter) and the existing sound level meter displaying only the measured value were compared at the actual measurement site. From the comparison, it was found that the hue sound level meter has better visual display and the display represents the auditory sense. From the foregoing results, it is possible to promote general understanding of the physical index.

Annoyance to noise is probably a good measure of the potential for complaint and community action. Each individual's degree of annoyance to noise cannot be accurately predicted from conventional laboratory studies and social surveys. Therefore, a logistic prediction model for individual allowable noise levels has been developed. In a previous paper [K. Furihata et al., Acta Acust. Acust. 93, 73-83 (2007)], an annoyance scale using the most frequently used annoyance ratings related to noise for community noise assessment in Japan was constructed. The dose-response relationships were obtained by actually listening to sounds in a field situation (1474 subjects) carried out at 14 metropolitan cities in Japan. The logistic prediction model was developed using the logistic regression parameters estimated from each cumulative percentage curve of seven annoyance scale scores based on all data (n=2940). To verify the hypothesis, individual relationships between annoyance and L(Aeq, (5 min)) for 24 normal-hearing subjects were constructed using a laboratory experiment. The main conclusion drawn from the results is that if at least one dose-response relation is obtained from each subject, the model can predict whether a sound is annoying or not from its L(Aeq,(5 min)) value. Moreover, validation of the model is needed in a field situation.

In addition to reporting the results of measurements of existing environmental noise and the results of calculations of noise from projected activities, the application of color for representing in terms of noise zones may be useful (ISO 1996‐2). Between color and noise, in spite of differences, there exists an interaction, although the connection between the visible and the audible expression is subjective. Subjectivity can in a given moment become objective, if one succeeds in unifying the visible and the audible. In the case of colored paper on a white background, the relation between the hue level expressing the psychological effect (annoyance) and LAeq(5min) (dB) of typical noise sources was discussed in a laboratory experiment. According to the obtained noise‐rating scale, the seven‐hue scale and LAeq(5min) are correlated well (r=0.874) as follows: white (value V9; not at all bothersome) ⇔ below 26 dB, light blue (hue 2.5B, value 8/chrome 4; not bothersome) ⇔ 26 to 37 dB, light green (2.5BG, 7/8; no...