Study on the effects of the harmonic choir stalls in the Church of the Certosa di San Martino in Naples

Abstract

The Church of the Certosa of San Martino was built in the 14th century and is characterized by the presence of an elliptical harmonic box built under the floor of the choir stalls, with which it communicates through openings in the floor. The harmonic box was made to remedy sound defects that appeared in the Church after the opening of several windows in the upper part of choir stalls and nave. The opinion of the monks was that these acoustic flaws caused their chants vibrations to be weakened and even lost. This work verifies whether the elliptical volume constructed below the choir stalls has any acoustic purposes. Acoustic measurements were carried out in its current state and then closing the connecting openings between the choir stalls and the cavity below, so as to assess any changes in the acoustic characteristics. The acoustic measurements were carried out by placing a sound source both in the choir stalls and on the altar, along with microphones in the choir stalls and the nave. At the end of taking the measurements, a change was observed in the acoustic parameters EDT, C₈₀, and D₅₀ only when the sound source is in the choir stalls.