Rich data trove gathered as a result of a unique opportunity with a capacity audience

Abstract

When an opportunity arises to perform an occupied room measurement, normally a short time is allotted to acquire data in order to minimize event disruption and audience discomfort. We therefore consider ourselves fortunate if one or two data sets are obtained under those conditions. An extremely rare—perhaps unique—opportunity arose from a confluence of factors: a 1600-seat concert hall at Liberty University, with a purposely over-sized area of movable curtains and banners to adjust the architectural reverberation; an installed active acoustics system, Constellation by Meyer Sound; a concert comprising distinct performances by orchestra, choir, and amplified worship band, with intermission to reset the architectural acoustics; and an interested client. The Constellation system provides 48 microphones distributed throughout the space, so a single set of sweeps through a system loudspeaker results in 48 measurements. The variables tested were (a) adjustable acoustic absorption in and out; (b) full audience in and out; and (c) a nominal Constellation setting on and off. Measurement analysis both confirmed design intentions and elucidated the behavior of the two adjustable acoustic systems in the occupied and unoccupied hall. The architectural and active acoustic system designs, performance, measurements, and usage recommendations will be discussed.