Year: 2026 | Month: June | Volume: 13 | Issue: 6 | Pages: 534-541
DOI: https://doi.org/10.52403/ijrr.20260651
Frequency-Dependent Comparison of Measured and Sabine-Predicted Reverberation Times in a Concert Hall
Damian Lengacher1, Lars Arnold Ritter2
1Independent Researcher, Switzerland; 2Independent Researcher, Switzerland..
Corresponding Author: Lars Arnold Ritter
ABSTRACT
This study examined how closely the simple Sabine equation predicted the reverberation time of a working concert hall, and how its agreement with in-situ measurements varied across frequency. The hall, a multi-purpose music club of about 665 cubic metres, was surveyed geometrically, and the area and material of every interior surface were recorded. Equivalent absorption areas were derived for the octave bands from 125 to 4000 hertz from published absorption coefficients, and reverberation times were calculated with the Sabine equation. Measurements followed the procedure of the international standard for performance spaces, using an omnidirectional dodecahedron source combined with a subwoofer, a calibrated pressure microphone, and a logarithmic sine sweep. Three source positions and up to nine microphone positions were combined, and the late decay was evaluated and doubled to obtain the reverberation time. The single-number average across the six bands agreed closely, differing by less than two per cent. The band-by-band picture differed sharply. At 125 hertz the measured reverberation fell about 59 per cent below the Sabine value, whereas between 1000 and 2000 hertz it lay roughly two thirds above the calculation; agreement was closest near 250 to 500 hertz. The findings showed that broadband agreement can mask large, opposing frequency-dependent errors, and that measurement remained indispensable when an existing room was to be optimised.
Keywords: reverberation time, room acoustics, Sabine equation, equivalent absorption area, octave-band analysis, concert hall .
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