Room acoustics in churches for oral tradition polyphonic chants

Overview

Romanic church @ Unarre

Romanic church @ Unarre

The aim of this work is to verify wether, for the oral transmitted traditional music research, ethnomusicologic view is not sufficient and it requires some empirical knowledge of the environment. In other words, we propose a multidisciplinar study to establish a relationship between the sound ideal and the analyzed sounds. This research focuses on room acoustics of different churches and oratories to determine how they can influence to the oral tradition polyphonic chants performed there.

Team

This research is in collaboration with Jaume Ayats (researcher at UAB and director at Museu de la Música) and Iris Gayete (Researcher at UAB).

Introduction

 

Musical Analysis

Acoustic measurements

Location of measured churches at the Pyrenées.

Location of measured churches at the Pyrenées.

We have measured the Impulse response, FRF and RT60 from 11 different churches at the pyrenées.

All of them are small churches with a small choir for the singers, usually made of wood, over the main entrance, in the opposite side of the altar. This is the typical internal distribution for early baroque decorated churches, even the origin of the church is older. Some of them are in good conditions while others are not. In general, churches which have been recently reconstructed do not preserve the original reverberation properties, changing wall surfaces, choir properties, etc. but they keep the overall structure, preserving the acoustic room mode distribution.

To establish the relationship between the singed chants and the acoustic properties of the churches, we focus on the measures of the Reverberation Time (RT60) and the Frequency Response function (FRF). We obtained a set of three measurements for each church, selected according to the communication paths during the ceremony: (a) priest to parishioners: both loudspeaker and microphone in the main space of the church, with the loudspeaker near the altar in a non symmetrical position with respect to the geometrical axes, and the microphone in the parishioner’s area in a non symmetrical position with respect to the geometrical axes, (b) chanters to parishioners: the loudspeaker upstairs in the choir in a non symmetrical position with respect to the geometrical axes, and the microphone in the parishioner’s area in a non symmetrical position with respect to the geometrical axes, and (c) chanters to chanters: both loudspeaker and microphone upstairs, in a non symmetrical position with respect to the geometrical axes.

 

Conclusions

Summary of measured FRFs at different churches

Summary of measured FRFs at different churches.

Summary of the RT60 measurements at different churches.

Summary of the RT60 measurements at different churches.

Other  FRF and RT60 measurements for specific churches can be found in this picasaweb album.