The position of the sound source in churches

Abstract

The position of the sound source is an aspect rarely considered in room acoustics because the shape of the space and its internal organization generally make clear where the sound source should be. However, this may not be the case in some buildings, such as churches. In these buildings, the source is not located in one position, but it moves from choir to the altar or the pulpit. This makes problematic the analysis of church acoustics. In particular, if the reverberation time is almost constant whenever the source may be, other acoustic parameters strongly depend on the position of the sound source. This paper focuses on the effect of the position of the sound source over the early lateral fraction and the center time. First, the results of computer simulations allow discussing the influence of some locations of the organ: above the entrance, in the middle of the room, between the altar and the worshipers, and behind the altar. Then, the values of the acoustic parameters for different sound sources are evaluated. In particular, the effect of speaking from the pulpit or from the altar are compared. Finally, suggestions to evaluate several positions of different sound sources in churches are reported.