RICERCA ITALIANA     

Acoustics of worship spaces

Politecnico di Bari

Abstract

The present research program aims at contributing to the study of worship buildings acoustics which, according to the proposers, is not studied enough both on a national and international level. In fact, there is a wide scientific literature about theatres and concert halls, but the same is not true for churches and other worship spaces. In addition, such buildings are much more complex both because of the complicated volumes (made of transepts, naves, domes and so on), and because of the different acoustic characteristics required by the most frequent kind of sound messages (speech and music) that propagate inside. The proposed research follows the work began by two of the three sub-units during the PRIN 2003 and is focussed on several aspects of church acoustics: the definition of a specific measurement protocol; the propagation of sound in such places; the characterization of the materials; the relationship between geometric and acoustic parameters; the study of the optimal listening conditions for both speech and music; the validation of simulation programs in complex spaces.
The definition of a specific measurement protocol and the study of sound propagation in churches will be developed in strict cooperation between the proposing research units. In particular, the study sound propagation will be investigated in two ways: the research units of the Politecnico di Bari and of the University of Pavia will study the problem using, respectively, scale models and >>>

Principal Investigator

Ettore CIRILLO Politecnico di BARI

Research Objectives

The modern science of architectural acoustics provides powerful instruments to investigate the delicate relations between a musical composition, its interpretation, and the space in which it is played.
The best orchestra directors often use the acoustics of the places in which they perform as well as musicians use their instruments. So it can be reasonably supposed that also the best composers created their masterpieces taking into account the acoustics of the places in which the music had to be played. The relation between music and architecture is likely to have been clearer to musicians than to architects. In fact, the history of architecture shows that architects were, in most of the cases, unaware of the acoustical requirements of the buildings they created in order to achieve an optimal balance of form and function. However, Gregorian chants sound better in the large, resonant cathedrals in which they were originally sung. In fact, the melody of the Gregorian chants takes advantage of the long reverberation of the Romanesque and Gothic churches (mostly made of stone), to produce an harmonic effect given by the superposition of the slowly decaying sounds. Similarly, Willaert and Gabrieli took advantage of the architecture of St. Mark's Basilica in Venice by dividing the choir into two groups located at opposite positions in order to produce (together with the orchestra and the church echoes) a rich, colourful, and rhythmic polyphony. Similarly, J.S. Bach composed >>>

Timescale

24 months

National and international background

The study of the acoustic characteristics of churches begun in the fifties, when Raes and Sacerdote [1] analysed the Roman Basilcas of St. John in the Lateran and St. Paul outside Walls. In the next years few papers were written about other Roman churches [2], about a group of Spanish, English and French churches [3], about Byzantine churches in Thessalonika [4,5], and about St. Paul Cathedral in London [6]. Later on, Giulianini and Cocchi [7] studied the churches of S. Andrea in Mantova and St. Petronius in Bologna. Another experimental survey was carried out in the monastery of Santo Domingo de Silos in Burgos (Spain) by Recuero, Gil and Gonzales [8]. In 1994 Lannie and Soukchov [9] published experimental results of five Russian tent-shaped temples.
All these works were essentially based on reverberation time measurements. Only recently other acoustic aspects have been taken into account. Among them, the speech intelligibility was measured in a large group of Swiss churches [10,11], and in an even larger group of Portuguese churches [12-20]. The latter research introduced the measurement of several acoustic parameters, and in particular, those used to characterize concert halls acoustics. In addition subjective listening tests were performed by a group of selected listeners. The most important results of Carvalho's research refer to the existence of correlations between acoustic and architectural parameters [12,13], the dependence of acoustics on architectural >>>