How to Improve Classroom Acoustics Without Spending Too Much

What is it about?

Have you ever struggled to understand a lecturer because of echoes in a classroom or noise from the air-conditioning system? Poor classroom acoustics can make listening difficult, affect communication and reduce the effectiveness of teaching and learning. This research investigates how two university lecture rooms at Universiti Malaysia Sarawak (UNIMAS) can be improved through affordable acoustic design solutions. The study involved actual sound measurements and computer simulations to evaluate the existing conditions and test different improvement strategies. The findings revealed that both lecture rooms had excessive sound reverberation, while operating air-conditioning systems significantly increased background noise. The research explored seven low-cost treatment alternatives using materials such as velvet curtains, corkboard and dense curtains, alongside a commercially available acoustic treatment for comparison. The results demonstrated that carefully selected and positioned materials, particularly ceiling treatments, could substantially reduce echoes and improve speech communication. The study also examined sound amplification systems to support clearer communication in suitable acoustic conditions. Importantly, the proposed low-cost treatment solutions could improve the lecture rooms for less than RM6,500, potentially saving up to RM23,000 compared with commercial acoustic treatments. This research demonstrates that better classroom acoustics do not always require expensive products. With appropriate design decisions and affordable materials, existing educational spaces can be transformed into more comfortable and effective learning environments.

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Photo by Dom Fou on Unsplash

Photo by Dom Fou on Unsplash

Why is it important?

This research addresses a practical and increasingly important challenge in educational building design: improving classroom acoustic conditions without imposing substantial financial burdens on educational institutions. Unlike studies that focus primarily on commercially available acoustic products, this investigation explores affordable, feasible alternatives made from readily accessible materials. What makes the research distinctive is its integration of on-site acoustic measurements, validated ODEON computer simulations and cost estimation to evaluate the effectiveness and economic feasibility of different treatment strategies. The investigation of two university lecture rooms at Universiti Malaysia Sarawak identified excessive reverberation and background noise associated with mechanical ventilation systems as key acoustic challenges. Seven low-cost treatment configurations were subsequently examined, demonstrating the importance of appropriate material selection and ceiling treatment in reducing reverberation. The study also highlights that speech intelligibility depends on the combined influence of reverberation time, background noise and sound amplification. Particularly significant is the economic potential of the proposed solutions, which could improve existing learning spaces for less than RM6,500 while offering savings of up to RM23,000 compared with commercial acoustic treatments. These findings are especially relevant to universities, schools and educational authorities seeking practical approaches to upgrading existing facilities within limited budgets. Ultimately, the research promotes a more economically accessible approach to architectural acoustics, demonstrating that effective learning environments can be achieved through thoughtful design, appropriate material selection and evidence-based acoustic interventions.

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