Braxton Boren

Archaeoacoustics of Mexico City's cathedral

We consider the acoustics of the architectural design of Mexico Citys Cathedral. Using measurements of the impulse response of the building and a virtual reconstruction of the architectural space, the reconstruction of the soundscape is developed with statistical and geometric methods and a standard computational platform (EASE). This reconstruction and contrast of experimental and simulated results allow to pose meaningful hypotheses related to the acoustical functionality of this temple, which played and continues to play a significant role in the religious and social activities of the country. We also present possible connections with other architectural, historical, and musicological aspects.

A generalized version of the Lubman-Kiser theory of historical acoustics and worship spaces

Although some relationship between liturgy, theology, and acoustics has been inferred by architectural acousticians at least since Hope Bagenal, this phenomenon has best been cataloged in a brief paper by Lubman and Kiser (ICA, 2001). Although all historical theories are difficult to distill in a single sentence, it might be briefly summed up as the statement that all things being equal, a change in acoustical conditions will result in a change in liturgy, and a change in theology will result in a change in acoustical conditions. This is usually described along a one-dimensional continuum between greater clarity or greater reverberance, and Lubman and Kiser describe much of this motion along this continuum throughout the history of the Western church through the Protestant Reformation and up to the present day. An attempt is made to generalize this theory and to examine whether the Western acoustical progression is mirrored in the historical experiences of other religious traditions and cultures.

Outdoor oratory and performance space

Spoken sermons and oratory in the West have usually been confined to the interior of churches or parliaments that bear similarities to traditional concert halls. However, the largest crowds in history are described as being outside due to the size constraints of most interior spaces. Historical estimates of crowd sizes or the intelligible range of speakers have generally been quite speculative. However, recent work has used an acoustical experiment by Benjamin Franklin to estimate the 1 m on-axis average SPL of the Anglican preacher George Whitefield at 90 dBA. Computational simulation of Whitefield’s preaching in London confirms Franklin’s estimate that he could have been heard by crowds of 30,000 or more depending on weather conditions and crowd noise. Using Whitefield as a benchmark, other historical orations may be evaluated based on geometric and acoustic factors. Within this framework, speeches given by Pericles, Demosthenes, Alexander the Great, and Julius Caesar are examined based on the size and ...

The maximum intelligible range of the unamplified human voice

The Anglican preacher George Whitefield preached to some of the largest reported crowds in recent history during the Methodist revivals in 18th century London. Benjamin Franklin later performed an auditory experiment in Philadelphia from which he estimated Whitefield could be heard by 30,000 listeners at once. Using the data from Franklin’s experiment and acoustic model of colonial Philadelphia, Whitefield’s on-axis averaged sound pressure level at one meter has been calculated to be about 90 dBA, consistent with the loudest values measured from trained vocalists today. Using period maps and topological data, acoustic models have been constructed of the sites of Whitefield’s largest crowds in London, using a human voice source with the projected SPL for Whitefield’s preaching voice. Based on the total audience area whose speech transmission index value is greater than that at Franklin’s position in the Philadelphia experiment, the total intelligible audience area can be calculated. Using Franklin’s own cr...

Sound radiation of trained vocalizers

Current research at NYU has focused on the maximum crowd size that could hear a single unamplified voice, including the impact of vocal directivity. Most literature on the radiation of the spoken voice has focused on the context of conversation in workspaces and thus has not investigated oratorical speech at high levels. Trained actors and singers, however, employ more methods of projection than are used in conversational speech and can achieve higher loudness as well. The radiation patterns from these types of communication have not been quantifiably studied yet. This paper investigates the horizontal plane radiation patterns of different methods of projection in trained vocalizers using relative intensity levels at 60 cm from the front of the speaker. In general, the method of production is not found to have a strong effect on the horizontal plane directivity.

Computer simulation of Benjamin Franklin's acoustic experiment on George Whitefield's oratory

The Anglican preacher George Whitefield was renowned for his loud voice and the huge crowds he drew during the transatlantic revivals of the 18th century. Benjamin Franklin was skeptical of the accounts of crowds of 30,000 gathering in London, and when Whitefield came to Philadelphia in 1739, Franklin performed one of the earliest recorded ‘archeoacoustic’ experiments: walking backwards down Market Street, Franklin continued listening to Whitefield speak from the old courthouse until his sermon became unintelligible. Using this maximum intelligible distance, Franklin calculated that Whitefield probably could have been heard by more than 30,000 listeners. Using Franklin’s account and period maps and prints of the colonial city, we have built a virtual CAD model of Philadelphia as it would have existed during Whitefield’s visit. This paper discusses techniques employed using geometric acoustic simulation software to approximate the loudness of Whitefield’s voice based on the STI at Franklin’s position. To d...

Acoustic simulation of the church of San Francesco della Vigna

A computer simulation study has been carried out of the acoustics of the Church of San Francesco della Vigna in Venice with a view to understanding whether or not the recommendations of the Renaissance scholar Francesco Zorzi would have improved the acoustics of the Church for the preaching of sermons. The flat coffered ceilings he recommended have been incorporated into the computer models but little improvement was found, even in the most extreme modifications studied.

Acoustic simulation of renaissance Venetian churches

The Venetian Renaissance was a confluence of innovative expression across many artistic disciplines. While architects like Palladio and Sansovino were designing architectural masterpieces in many of the churches built during this period, composers such as Willaert, the Gabrielli, and Monteverdi were composing complex polyphonic works for split-choir ensembles, exploring the tonal and spatial dimensions of musical performance. The large churches built during this period have extremely long reverberation times and provide low clarity for understanding the complex polyphony composed for these spaces. This paper uses modern acoustic simulation techniques to provide insights into the acoustics of large Venetian churches as they would have existed during the Renaissance. In consultation with architectural historians, the authors have collected data on the structure and layout of Palladios Redentore and San Marco on festal occasions, when large crowds, extra seating, and wall tapestries would have provided extr...