Study on the Acoustic Environments in Public Spaces

通过现场测量和室内实验，对火车站、机场航站楼、地下商业区等不同类型的公共空间的声学状况进行了基础性研究。本课题是在对公共空间声环境进行了多年的初步研究的基础上，于1995年开始的，主要包括物理调查和心理实验两部分内容。首先，在JR横滨站周边地下空间的三个区域进行了声环境状况的现场测量，在白天测量了实际环境噪声，并测量了建筑声学指标（混响时间、声压级分布等）。在午夜测量。为了研究公共空间的心理声学感受，本研究采用了一种新的声场模拟技术，即在消声室中设置一个由6个指向性传声器组成的三维声接收系统和一个多通道声再现系统。利用该技术，结合现场实测数据，对公共广播系统的噪声和易听性进行了两种主观听觉测试，探讨了公共广播系统的心理声学特性与建筑声学条件的关系。

Basic investigations on the acoustical conditions in various types of public spaces such as railway stations, airport terminals, underground commercial areas were made by field measurement and laboratory experiments. This research project started on 1995 based on the preliminary studies on acoustic environments in public spaces made for several years.This research consists of two main contents : Physical investigations and psychological experiments. At first, the field measurements of acoustic environmental conditions were performed at three areas in the underground spaces around the JR Yokohama Station, in which the actual environmental noise was measured at daytime and the architectural acoustic indices (reverberation time, sound pressure level distribution and etc.) were measured in midnight. Based on the measurement results, the relationship between the architectural conditions and the acoustic characteristics were investigated.In order to investigate the psycho-acoustical impression in public space, a new sound field simulation technique has been developed in this study, in which a 3-dimensional sound receiving system consisting of six directional microphones and a multi-channel reproduction system set in an anechoic room are used. By using this technique and the data obtained in the actual fields, two kinds of subjective hearing tests on noisiness and easiness of hearing of public address system were performed and the relationships between the psycho-acoustical attributes and the architectural and acoustic conditions in the spaces were investigated.