The significance of the church occupancy in the RASTI values in a Catholic church

Abstract

This study reports on Rapid Speech Transmission Index (RASTI) field measurements made in a 17th century Portuguese Roman Catholic church. One source location (main altar area) was used in an empty and occupied same church, with and without the use of its own sound reinforcement system. This paper concentrates on the relationships of the RASTI values with the effect of the presence of a full occupancy in the church. The mean RASTI values in the church varied from 0.31 to 0.64 (non-occupied church) and from 0.32 to 0.56 (occupied church). The results show that the presence of persons, considering all receiver positions within the church, increases on average, 0.02 in the absolute RASTI values (or 7 per cent in the relative RASTI values) with the PA system off and about 0.05 (or 10 per cent) with the PA system on.