An Intelligent Classroom Noise Monitoring System Using Sound Sensors and Multi-Threshold Alert

by Cyrus A. Jimenez, Engr. Bernard C. Fabro, Francis Angelo Q. Rique, Karl Kenneth A. Botalon, Kristine Anne R. Laput, Russel S. Del Rosario

Published: January 24, 2026 • DOI: 10.51244/IJRSI.2026.13010031

Abstract

Classroom noise is a common problem that can disrupt learning, reduce student focus, and make it difficult for teachers to deliver lessons effectively. To address this issue, this project presents a microcontroller-based classroom noise detection system that provides visual and audible feedback when noise exceeds a set threshold. The system uses a sound sensor (FC-04) to measure ambient noise levels in real-time and a microcontroller to process the input. Noise levels are indicated using three LED indicators — green for acceptable noise, orange for moderate noise, and red for high noise — while a buzzer provides an audible alarm when the noise exceeds the acceptable limit. The system is designed to help students become more aware of their noise levels and encourage a quieter, more productive classroom environment. By integrating hardware and simple programming, the system provides a reliable and automated approach to classroom noise management without relying solely on verbal reminders from teachers. In addition to classrooms, the system has potential applications in libraries, hospitals, industrial settings, and examination halls, where controlling noise is important for safety, focus, and comfort. The modular design also allows for future improvements, such as adjustable thresholds, data logging, or integration with automated monitoring systems. Overall, this project demonstrates the practical use of technology to improve discipline and maintain conducive learning environments. The system is simple, cost-effective, and can be easily implemented in educational settings to promote better concentration, minimize distractions, and enhance the overall teaching and learning experience.