D'autres Soleils - Festyvocal 2023
Luna Valentin


The Church ... And its acoustics

Week 1

The Église Le Corbusier, also named Saint-Pierre Church in Firminy, is an architectural masterpiece designed by the renowned Swiss-French architect Le Corbusier. It is located in Firminy, a town in the Loire department of France. The construction of the church began in 1960 and was completed in 2006, long after Le Corbusier's death in 1965. The building, made of reinforced concrete and glass, is characterized by its innovative design and unique features, including its bell tower, which stands at a height of 60 meters. The interior of the church is also impressive, with its tall and spacious nave, stunning stained-glass windows, and the use of natural light. The church is now considered one of the most important landmarks in Firminy and attracts visitors from all over the world who come to appreciate the beauty and significance of this architectural masterpiece.



In 2020, I started an internship with Festyvocal; my task was to study the unique acoustics of the Le Corbusier Church in Firminy. A 13-second reverberation time had been measured by ear when the church was empty, and nine seconds of reverberation with an audience. Upon conducting my observations, I found that the frequency response of the church exhibited a strong amplification of low frequencies up until 400 Hz, but that the high frequencies remained less prominent than expected. My experiments showed that the location of the sound source and receiver had little effect on the frequency response (see Frequency Responses Graph), with the exception of a few echo phenomena observed locally. When measuring the reverberation time of the church, I found that the RT30 is indeed around 13 seconds at 400Hz when the church is empty as measured empirically (See RT30 Graph).



Map of the church and locations of acoustical measurements (R = receiver location, A:L = Source locations), and Spectrograms of IRs at locations A, B and E. An echo is visible on the Spectrogram of location B.

Week 4

In progress :
- IR documentation
- Toturial on convolution reverb in reaper with IR
- CAVIAR ... is working (sometimes)

Week 5 & 6 - IRs, more IRs

All IRs are finally ready to be used, and available here : Acoustics I am still working on the documentation / user manuel of the IRs.
The Caviar works !!! (occasionally...)

Final

Demo Visit of Le Corbusier Church



Documentation PDF : documentation