Acoustical simulation and optimization in Mosques

Wasim Orfali

doi:10.59400/sv3217

Acoustical simulation and optimization in Mosques

Wasim Orfali
Architectural Engineering Department, College of Engineering, Taibah University, P.O. Box 344, Madinah 41411, Saudi Arabia

Article ID: 3217

DOI: https://doi.org/10.59400/sv3217

Keywords: acoustic performance; electro-acoustic; architectural acoustic; mosque acoustic; acoustic simulation

Abstract

This article discusses the assessment and optimization of speech intelligibility in the Grand Mosque in Makkah. It is the most iconic Islamic site in the world. Most of the surface material used is marble, which is considered to be a highly sound reflective material. Acoustic measurement of the current conditions (with a surface area of 85,000 m²) was conducted. A virtual model was used to obtain an optimum acoustical solution. The measurement and inspection of ambient acoustical data were conducted using the EASERA measuring tool, and as a result, late energy arrival (after 100 ms) was noticed; this forms echoes and decreases intelligibility. It was also noticed that the measured background noise levels were as high as 90 dB (A). High temperature and humidity degrade the quality of the ambient acoustical environment. A virtual model for the targeted areas (Massa roof and adjacent perimeter) was created using EASE simulation software. Mapping results showed a high level of intelligibility (0.6) and homogenous distribution of the sound pressure level (SPL) (max. variation 9 dB). Loudspeaker columns minimized late energy arrival. The “active” approach improved the ambient acoustical environment in the targeted area and eliminated the necessity of an expensive “passive treatment”.

Published

2025-11-17

How to Cite

Orfali, W. (2025). Acoustical simulation and optimization in Mosques. Sound & Vibration, 59(6). https://doi.org/10.59400/sv3217

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Issue

Vol. 59 No. 6 (2025)

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Article

This work is licensed under a Creative Commons Attribution 4.0 International License.

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