Pre-restoration characterization of acoustical heritage of Nossa Senhora do Pilar church, Goa

Abstract

The church of Nossa Senhora do Pilar built in 1613 by the Spanish Franciscan Capuchos is part of the Convento do Pilar, Goa. This diminuted sanctuary church with Rococon Mannerist features underwent repairs wherein the original lime mortar mix on its laterite stone walls was replaced by cement plaster - paint coat and ceramic tiles. Besides triggering a salt attack, the replacement of original lime mortar caused a change in the surface sound absorption values inside the church. The acoustical properties inside the church too suffered change. The restoration of this 400 year old church has begun. A method of capturing the acoustical sacred heritage of the church using objective acoustical parameters (RASTI, RT, D50, C80, TS, ITDG, G, and LAeq) and subjective acoustic impressions is presented in this study. The values obtained in this pre-restoration survey will be compared with those obtained through a similar acoustical characterization of the worship ambience inside the church after the inner surface of the walls is replastered with the original lime-mortar overcoat. This will enable a comparative explanation of the restoration of the acoustical heritage of Nossa Senhora do Pilar church.