A Factor Analysis Approach to Determining a Small Number of Parameters for Characterising Halls

Abstract

Specialist bibliographies reveal that there are many parameters for fully describing the acoustics of a hall. Are all of these parameters absolutely necessary? Although hall acoustics is a complex discipline, we can nevertheless see that many parameters measure aspects that are very similar to musical perception. Our aim in this paper is to use factor analysis to find a small number of statistically independent parameters that will enable musical performance halls to be characterised using just a few parameters. At the same time, we aim to identify other parameters that will be useful to researchers as part of a lineal combination. To achieve this, we have measured impulse responses in 17 halls and determined the most common 18 parameters. By using factor analysis, we have identified the three key factors that satisfy the required characteristics. This result confirms those obtained in an earlier study [1] of nine halls. The factors obtained strongly correlate with other classic parameters. Factor 1 correlates with reverberation time; Factor 2 correlates with the objective parameters for the impression of space; and Factor 3 correlates with parameters of strength. This last factor also correlates strongly with objective parameters for listener envelopment (LEV) [2]