Highway noise barrier perceived benefit

Annoyance judgment was made by magnitude estimation, with noise of eight spectra, under three intensities of illumination (0.25, 2.05, 12.50 fc, achromatic). Subjects were intermediates, or ambiverts, as defined on scores of a personality inventory. Two degrees of octave‐band energy attenuation, four center frequencies for this attenuation, and three overall intensities constituted the noise stimuli. The prediction was that intensity of illumination and noise frequency spectrum influence annoyance judgment; each depending on the overall noise intensity. Analysis of variance showed significant results for illumination intensity and noise spectrum. Annoyance decreased at “weak” illumination with the noise of lower‐frequency attenuation (centered at 800 Hz) as compared with the control noise (without attenuation) while annoyance decreased at “intermediate” illumination with noise of intermediate‐frequency attenuation (centered at 1.6 kHz), and annoyance decreased at “strong” illumination with noise of higher‐frequency attenuation (centered at 4 kHz). Thus, an upward shift of effective frequencies of band attenuation for annoyance reduction was evident along with an increase in illumination intensity. Results were consistent with the prediction, and degrees of energy attenuation and overall noise intensity differentiated this prediction.

T. Shigehisa

Papers

Noise annoyance judgment as affected by intensity of illumination and noise spectrum