Chamber musicians’ acoustic impressions of auditorium stages: relation to spatial distribution of early reflections and other parameters

<div>Characterizing stage acoustics using objective parameters has seen some recent resurgence—several studies have noted the importance of the <i>directionality</i> of early stage reflections to musicians, which is not adequately represented using existing <i>omnidirectional</i> stage-support parameters. This study examines the subjective impressions of 19 chamber musicians against omnidirectional [reverberation time, early and late support (<i>ST</i>_Early, <i>ST</i>_Late), etc.], and proposed spatially-defined parameters (<i>TH</i> and <i>TS</i>), along with simple ratios of stage dimensions derived from measurements on eight purpose-built stages. <i>TH</i> is a ratio of early energy from “above” to that from the “horizontal,” while <i>TS</i> relates energy from above to that from the “sides” of the stage. Robust mixed-effects analyses showed that the musicians' overall acoustic impression ratings are predicted (i) by <i>TH</i> within a linear model; (ii) by <i>TH</i> × <i>ST</i>_Early, <i>TH</i> × <i>ST</i>_Late, and <i>TS</i> × <i>ST</i>_Early, <i>TS</i> × <i>ST</i>_Late; (iii) by <i>ST</i>_Early, <i>ST</i>_Late each within parabolic models; and (iv) by several architectural parameters' linear and parabolic models. These findings reinforce recent studies of spatially-defined parameters to more fully account for the subtleties of onstage sound fields. Some simple design recommendations are presented, although future studies are needed to confirm these findings/recommendations for a wider range of auditorium stages.</div>