The effect of performance stages on subwoofer polar and frequency responses

Abstract

Precise control of low-frequency energy is a common requirement at large-scale live events, whereby sound energy transmitted into performance areas and outside event grounds must be limited. Industry-standard sound system design and prediction software typically omits any acoustical effect a performance stage will have on the overall system response (both in terms of polar and frequency response).This research highlights the significant effect a stage can have on subwoofer performance, where in particularly poor cases directionality is lost and the frequency response is strongly colored by resonances. This work puts forward recommendations for subwoofer system configurations that avoid unwanted stage effects as much as possible to maintain the desired (and predicted) system performance.