Abstract
In the field of sound environmental design, designers have concentrated their efforts on improving sound physical properties such as decreasing noise level or improving sound articulation and so on. However, the benefits provided by such improvements of sound physical properties are not necessary understood by the users except the visually impaired person or aged person. In order to clarify the benefits of sound environmental improvement, the contribution of the sound environmental functions to evaluation of product design is examined according to psycho-acoustical experiments, which is as a case study focused on an anti-noise umbrella. The anti-noise umbrella developed by authors provides quiet environment walking in the rain. Valuation of the umbrella is estimated by Contingent Valuation Method. It was found that the values of willingness to pay to the anti-noise umbrella increases and utilities were produced when the sound environmental function was shown clearly.
