1971 年 27 巻 3 号 p. 132-143
A new method based on spatial correlation techniques to evaluate the degree of diffuseness of the sound field in a reverberation chamber was described. Directional distribution of correlation coeffcients R_π were observed under various conditions in reverberation chambers, and a diffusitivity index R_π, was defined. Close dependence between R_π and measured reverberant absorption coefficients of the material was recognised. For the reverberation chamber in which R_π, is greater than 70%, it could be judged that its sound field would fulfil the requisite for the diffuse sound field, this being the premise of the reverberation chamber method.