Directional Analysis of Early Reflections in Small Shoebox-Shaped Listening Rooms

Critical listening rooms aim at providing an acoustically controlled environment for the accurate evaluation and production of audio content. In this study, the dimensions of existing ITU-R BS 1116-compliant critical listening rooms are surveyed using data obtained from existing literature and publications. To further understand the early reflection patterns in ITU-R BS 1116-compliant critical listening rooms, this study simulates first- and second-order reflections using the Image Source Method (ISM) for six different source positions and one listener position. Employing the agglomerative clustering (hierarchical) algorithm, the first and second-order reflections are analysed separately and visualised on the Mollweide projection. The results indicate a general agreement in the first-order reflection patterns across the rooms using six clusters, while the second-order reflection patterns are more dispersed within clusters. This study presents a general summary of the directional patterns of early reflections in critical listening rooms, and identifies regions that require further investigation to fully comprehend their perceptual significance.