Correlations of the Acoustic Fields of Mudejar-Gothic Churches

This paper studies the statistical correlations between monaural acoustic parameters with themselves and with architectural parameters from an acoustical survey undertaken in 12 Mudejar-Gothic churches in Seville, southern Spain. Objective room-acoustic parameters have been measured using impulse response analysis through a maximum-length-sequence measurement system in each church. Measurements cover time parameters (reverberation time, early decay time); levels (sound strength); energy-based parameters (centre time, clarity for speech, clarity, definition, early lateral energy fraction); and speech intelligibility (rapid speech transmission index) and the analysis takes into account both spatially averaged values and individual positions. The aim of the study is to identify the main architectural factors that have relevant influence on the acoustic fields of the churches, and the minimum number of room acoustic parameters which are able to describe adequately this acoustic field, thus the possible excess of information is evaluated. Significant correlations have been found that, in the best cases, correspond to fits using pairs of independent variables instead of one single variable. The best option to describe the six subjective attributes of sound perception in these buildings consists of three acoustic parameters formed by two different pairs plus the early lateral energy fraction.