Acoustic Phenomena in Javanese Gamelan: An Ethno-Physics Approach to Sound Waves, Resonance, and Spectrum Analysis in Physics Education
Linda Dwi Astuti, Dwikie Mahendra Sani, Bunga Nur Anas Thasia, Fina Husnawati

Universitas Sebelas Maret

Abstract

Physics education on sound wave concepts is often taught theoretically and detached from local cultural contexts. This study aims to investigate the acoustic phenomena in Javanese Gamelan instruments as an ethno-physics approach to innovating sound waves analysis in physics education. Utilizing a descriptive qualitative method that integrates software-assisted spectrum analysis, this study examines two main acoustic characteristics of the gamelan: the material quality in saron instruments and the self-beating phenomenon in pencon instruments (gong, kempul, and kenong). The spectrum analysis results reveal that the thickness and geometry of the saron blades are precisely engineered to produce clear tonal scales and prevent humming. Furthermore, the self-beating phenomenon in pencon instruments is empirically proven to occur due to wave interference within a single instrument- the pencu (central boss) and rai (face) produce the fundamental frequency, while the sisi (side walls) generate an overtone frequency approaching the kempyung or gembyang interval. The subtle difference between these internal frequencies creates a rhythmic beating effect. These findings confirm that the Javanese gamelan is not merely a performing arts instrument but a representation of highly sophisticated acoustic physics engineering. Integrating this ethno-physics study into the curriculum offers novelty in bridging local wisdom with comprehensive science understanding, making sound waves analysis materials more measurable and contextual.

Keywords: Ethno-physics, Javanese Gamelan, Sound Waves Analysis

Topic: Physics Education