Effect of architectural styles on objective acoustical measures in Portuguese Catholic Churches

Abstract

This study reports on acoustical field measurements made in a major survey of 41 Roman Catholic churches in Portugal that were built from the sixth century AD until 1993. The survey involved eight monaural acoustical measures that were taken at multiple source/receiver locations using the impulse response with noise bursts method - Reverberation Time (RT), Early Decay Time (EDT), Early to Late Sound Index or Clarity (C80), Early to Total Energy Ratio or Definition (D), Center Time (TS), Loudness (L), two Bass Ratios - and RASTI. This paper concentrates on one specific analysis regarding that survey: the effect of architectural styles on those nine acoustic measures. The hypothesis tested concerns the effect of architectural styles and their evolution through the last 14 centuries on some acoustic measures. The churches tested were grouped in 8 architectural styles: Visigothic, Romanesque, Gothic, Manueline, Renaissance, Baroque, Neoclassic, and Contemporary mainly regarding the style of their interior decoration, finishing and shape. Summary graphs showing statistical analyses of each parameter measured regarding the architectural styles are presented. A trend seems to be present in the variation of some acoustical measures through time and statistically significant differences can be found regarding some architectural styles.