Acoustical design of St. Margaret’s Chapel

Abstract

St. Margaret’s School is an all-girls high school located in the quiet, upscale Suginami Ward of Tokyo. The school’s St. Margaret’s Chapel was built some 70 years ago and included a pipe organ. The school decided to replace it with a new pipe organ and commissioned Taylor & Boodie, a U.S. organ builder. They requested adjustments to the chapel’s room acoustics so that the new organ would sound its best. Before the project began, the chapel’s reverberation time measured 1.4 s at 63 Hz and 1.8 s at 500 Hz and 1 kHz. That is, the reverberation time was shorter for low register sounds. The immediate challenge we faced on this project was the school’s requirement that the chapel not be altered at all visually. St. Margaret’s Chapel has historical value that the school wished to preserve. The framework of the chapel building and its floor are entirely made of wood. Moreover, the area around the altar is wood paneling. Upon investigation, we confirmed that the vibrations of these wood elements were absorbing the low register sounds. We determined that strengthening the walls and floor of the altar area would be an effective strategy to improve the chapel’s acoustics.