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ACOUSTIC EVALUATION OF MOSQUES WITH TWO LOUDSPEAKERS: INFLUENCE OF GEOMETRY, SIZE, CEILING MATERIALS, LOUDSPEAKER POSITION, AND OCCUPANCY
Abstract
Introduction. This study presents a comprehensive investigation of the acoustic characteristics of mosques equipped with two loudspeakers under varying conditions. It addresses the widespread challenge of poor acoustics in Indonesian mosques, which often results from architectural features, material choices, and suboptimal sound system design. Methods. Using acoustic simulation, the research systematically varied several parameters: geometry, prayer area size (ranging from 100 m² to 625 m²), ceiling material (acoustic tile ceiling vs. gypsum tile ceiling), loudspeaker position, and occupancy level (unoccupied vs. fully occupied). The primary focus is the optimisation of the Speech Transmission Index (STI) for speech intelligibility and Sound Pressure Level (SPL) uniformity. Results. The key findings indicate that loudspeaker placement (corner vs. center-front) does not significantly affect either STI or uniformity. However, in larger hall volumes (e.g., 3,516 m³ and 6,086 m³), minor differences in sound uniformity (SPL Max–Min) were observed depending on loudspeaker position. In contrast, room volume, ceiling material, and occupancy significantly influence STI; larger volumes and lower absorption are associated with reduced clarity. Sound uniformity is also negatively affected by increased room volume and reflective, complex ceiling shapes (e.g., pyramidal), whereas increased absorption can heighten the dominance of the direct sound field, potentially diminishing uniformity. Conclusions. The study establishes that to achieve an STI > 0.5 and SPL variation < 6 dB across all occupancy conditions, the mosque volume should not exceed 1,125 m³. Furthermore, to ensure adequate speech intelligibility (STI > 0.5) in the unoccupied (worst-case) condition, the maximum reverberation time (RT) at 1 kHz should be limited to 2.5 seconds. These findings provide practical, evidence-based guidelines for the acoustic design of small- to medium-sized Indonesian mosques.
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Abdou, A. (2003). Measurement of acoustical characteristics of mosques in Saudi Arabia. The Journal of the Acoustical Society of America, Vol. 113, Issue 3, p. 1505.
Abdullah, A. H. and Zulkefli, Z. A. (2014). A Study of the Acoustics and Speech Intelligibility Quality of Mosques in Malaysia. Applied Mechanics and Materials, Vol. 564, p. 129.
Adnan, N. A. et al. (2018). Acoustic Quality Levels of Mosques in Batu Pahat. In IOP Conference Series Earth and Environmental Science. IOP Publishing, p. 12009.
Ali, L. A. and Mustafa, F. A. (2023). Mosque Morphological Analysis: The Impact of Indoor Spatial-Volumetric Visibility on Worshipers’ Visual Comfort. Sustainability, Vol. 15, Issue 13, p. 10376.
American National Standards Institute (2017) ANSI/INFOCOMM A102.01:2017. Audio Coverage Uniformity in Listener Areas. American National Standards Institute [Preprint].
Arinta, R. T., Sari, T. D. S., Ashary, E., and Sulistiyoningsih, A. (2022). Acoustic Performance of Al-Muhajirin Mosque Semarang. International Journal of Innovative Science and Research Technology, Vol. 7, Issue 6.
Aydın, D. Ç., Kocyigit, F. B., and Dalkılıç, N. (2021). Assessment of the Acoustic Performance of Historical Structures That Shed Light on Today’s Technologies: Fatih Pasha (Kurşunlu) Mosque – Diyarbakır. DÜMF Mühendislik Dergisi [Preprint]. DOI:10.24012/dumf.949347.
Benferhat, M. L. et al. (2024). On the simulation of occupied acoustic conditions of Djedid mosque in Algiers. In Proceedings of the 10th Convention of the European Acoustics Association, Forum Acusticum 2023, pp. 2553–2557.
Bjor, O.-H. (2023). STIPA — The Golden Mean Between Full STI and RASTI. In Proceedings of Forum Acusticum 2023. DOI:10.25144/18155.
Budi, B. S. (2006). A Study on the History and Development of the Javanese Mosque Part 3: Typology of the Plan and Structure of the Javanese Mosque and Its Distribution. Journal of Asian Architecture and Building Engineering, Vol. 5, Issue 2, p. 229. DOI:10.3130/jaabe.5.229.
Din, N. B. C., Yong, L. H., and Razak, A. S. A. (2016). Relationship between room characteristics and speech intelligibility in contemporary churches in Malaysia. International Journal of Automotive and Mechanical Engineering, Vol. 13, Issue 2, p. 3451. DOI:10.15282/ijame.13.2.2016.13.0285.
Eldakdoky, S. (2016). Optimising acoustic conditions for two lecture rooms in Faculty of Agriculture, Cairo University. Ain Shams Engineering Journal, Vol. 8, Issue 4, p. 481. DOI:10.1016/j.asej.2016.08.013.
Elkhateeb, A. and Eldakdoky, S. (2022). The Optimal Reverberation for Masjids. International Journal of Architectural Engineering Technology, Vol. 9, p. 73. DOI:10.15377/2409–9821.2022.09.6.
Farrasti, N. A., Sarwono, R. S. J. and Mangkuto, R. A. (2024). Acoustic design simulation of a square-plan mosque based on optimisation using fair-weighted scoring. In Proceedings of ASim2024: The 5th Asia Conference of the International Building Performance Simulation Association. Osaka, Japan.
Fikriyati, U. (2023). Architectural Interpretations of Qur’anic and Hadith Influences in Traditional Indonesian Mosques During the Walisanga Era. Jurnal Studi Ilmu-ilmu Al-Qur an dan Hadis, Vol. 24, Issue 2, p. 253. DOI:10.14421/qh.v24i2.4657.
Fohhn Designer (2025). [online ]Available at: https://www.fohhn.com/en/catalog/fohhn-designer [accessed on: 12/04/2026].
Galbrun, L. and Kitapçi, K. (2014). Accuracy of speech transmission index predictions based on the reverberation time and signal-to-noise ratio. Applied Acoustics, Vol. 81, p. 1. DOI:10.1016/j.apacoust.2014.02.001.
Gül, Z. S., Çalışkan, M. (2013). Impact of design decisions on acoustical comfort parameters: Case study of Doğramacızade Ali Paşa Mosque. Applied Acoustics, Vol. 74, Issue 6, p. 834. DOI:10.1016/j.apacoust.2012.12.006.
Handryant, A. N. (2021). An Assessment of Acoustic Quality in Mosque Case Study: Masjid At-Tarbiyah UIN Malang. Advances in Social Science, Education and Humanities Research / Advances in social science, education and humanities research [Preprint]. DOI:10.2991/assehr.k.210421.032.
Ismail, M. R. (2013). A parametric investigation of the acoustical performance of contemporary mosques. Frontiers of Architectural Research, Vol. 2, Issue 1, p. 30. DOI:10.1016/j.foar.2012.11.002.
Jørgensen, S. (2014). Modeling speech intelligibility based on the signal-to-noise envelope power ratio. Research Portal Denmark, p. 194. Available at: https://local.forskningsportal.dk/local/dki-cgi/ws/cris-link?src=dtu&id=dtu-39f7e0df-652b-4d34-ba25-0734577828ec&ti=Modeling%20speech%20intelligibility%20based%20on%20the%20signal-to-noise%20envelope%20power%20ratio (accessed on: 16.08.2025).
Kaygısız, A., Semerci, F., and Sayın, R. T. (2024). Acoustic Analysis of the Masjid at Necmettin Erbakan University Köyceğiz Campus in Konya. Buildings, Vol. 14, Issue 10, p. 3330. DOI:10.3390/buildings14103330.
Kitapci, K. and Çelik Başok, G. (2021). The acoustic characterisation of worship ambiance and speech intelligibility in wooden hypostyle structures: The case of the Aslanhane Mosque. Acoustics Australia, 49, p. 425. DOI:10.1007/s40857-021-00238-1.
Kobayashi, Y. and Kondo, K. (2019). Japanese speech intelligibility estimation and prediction using objective intelligibility indices under noisy and reverberant conditions. Applied Acoustics, Vol. 156, p. 327. DOI:10.1016/j.apacoust.2019.07.034.
Kunchur, C. (2019). Evaluating Room Acoustics for Speech Intelligibility. Open Journal of Applied Sciences, Vol. 9, Issue 7, p. 601. DOI:10.4236/ojapps.2019.97048.
Latifah, F. N., Putri, R. S., Syukur, F., Sutarno, W. H., Paramita, B., and Ramadhan, T. (2023). An Analysis of Prayer Room Acoustics in the Pusdai Mosque in West Java. Engineering Proceedings, Vol. 53, Issue 1, p. 4. DOI:10.3390/IOCBD2023-15187.
Lukman, A.L. et al. (2023). The Dynamics of Interpersonal Space in Congregational Prayers in Salman Mosque Bandung During Covid Pancemic. Journal of Islamic Architecture, Vol. 7, Issue 3, p. 416. DOI:10.18860/jia.v7i3.18103.
Masih, D. A. A. et al. (2021). The assessment of acoustical characteristics for recent mosque buildings in Erbil City of Iraq. ARO-The Scientific Journal of Koya University, Vol. 9, p. 51. DOI:10.14500/aro.10784.
Oldham, D. J., Elkhateeb, A., and Science, B. (2008). The absorption characteristics of Muslim worshippers. Building Acoustics, Vol. 15, Issue 4, 335–348. DOI:10.1260/135101008786939946.
Othman, A. R. et al. (2016). The Importance of Acoustic Design in the Mosques towards the Worshipers’ Comfort. Procedia — Social and Behavioral Sciences, Vol. 234, p. 45. DOI:10.1016/j.sbspro.2016.10.218.
Pratiwi, R. U. et al. (2023). Optimising the Acoustic Condition of a Pyramidal-Ceiling Mosque Based on Simulation. Journal of Islamic Architecture, Vol. 7, Issue 4, p. 713. DOI:10.18860/jia.v7i4.19638.
Prawirasasra, M. S. and Mubarok, S. H. (2017). Evaluation of acoustical comfort in mosque. In IOP Conference Series Materials Science and Engineering. IOP Publishing, p. 12021. DOI:10.1088/1757-899x/211/1/012021.
Sarwono, S. J. et al. (2020). Peningkatan kualitas akustik masjid. Bandung: Institut Teknologi Bandung.
Sert, F. Y. and Karaman, Ö. Y. (2021). An Investigation on the Effects of Architectural Features on Acoustical Environment of Historical Mosques. Acoustics, Vol. 3, Issue 3, p. 559. DOI:10.3390/acoustics3030036.
Setiyowati, E. (2012). Strategies to increase the acoustical quality of the mosques without reinforcement system. Journal of Islamic Architecture, Vol. 1, Issue 1. DOI:10.18860/jia.v1i1.1714.
Sistem Informasi Masjid (2025). [online] Available at: https://simas.kemenag.go.id/ [accessed on: 24/06/2026].
Sudarsono, A. S. et al. (2019). The perception of sound quality in a mosque. AIP conference proceedings, 2088, p. 50007. DOI:10.1063/1.5095341.
Sudarsono, A. S. et al. (2023). Optimising the acoustic condition of a community mosque: Simulation-based approach. In. Springer, p. 693. DOI:10.1007/978-981-99-1403-6_46.
Syazana, W. P., Din, N. C., Yahya, M. N., Harun, Z., Yahya, K., and Junaid, T. (2023). The effect of diffusing acoustic panel on acoustical performance in a mosque with dome. AIP Conference Proceedings, Vol. 2530, Issue 1, 070002. DOI:10.1061/9780784479247.018
Yang, T. and Kang, J. (2021). Acoustic modeling of sequential spaces: A parametric study. Building and Environment, Vol. 212, p. 108733. DOI:10.1016/j.buildenv.2021.108733.
Zohra, B. H. (2016). The Numerical Simulation Support Tool for the Assessment of the Acoustic Quality of Worship Spaces. International Journal of Computer Science Engineering and Information Technology, Vol. 6, Issue 1, p. 1. DOI:10.5121/ijcseit.2016.6101.
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