The Ceramic Vessels of Trg: Acoustic Wall Construction in a Medieval Serbian Church

Abstract

This paper examines the existing acoustic conditions of the church in the village of Trg in eastern Serbia and investigates the acoustic effects of ceramic vessels originally embedded in the church walls but extracted when the church was restored to its original medieval layout in the 1980s. The impulse response of the church's interior space was measured in situ, providing the various acoustic parameters that numerically describe the acoustic field of a space, of which we particularly considered the reverberation time (T30), early decay time (EDT) and the speech transmission index (STI). We acoustically measured all of the eleven remaining intact vessels, and we built a 3D acoustic model of the vessels for the lab analysis. Our findings suggest that the vessels positioned as found during the restoration works—vertically, upside down, at a height of 3.75 meters, behind a thin stone facing—made no discernible difference in the acoustics of the Trg church. However, comparative research via similar studies of medieval churches suggest that the original builders may have misinterpreted the technology of acoustic vessels and may have installed them in a manner that disabled their possible effect on church acoustics.