Javanese Gong Acoustics and Its Modeling using Finite Element Method

In Central Java, the Javanese Gong is one of prominent gamelan instrument to mark the end of musical passage. The Gong is a distinctive percussion instrument because of its wave-like sounds after being struck immediately due to its traditional manufacture procedures. Spectra for the gongs vary substantially due to variation in shape and size, and to dimensional irregularities created during manufacture and whilst tuning by soft-hammering or hand-grinding. Finite Element Analysis is used to predict the effect of a range of variations of gong geometries on modal shapes as well as modal frequencies. The radiated sound spectra of the gong are also measured and compared with the natural frequencies obtained from Finite Element Analysis. Through the finite element model, the effect of geometric dimensions and material properties of the gong on its sound characteristics can be predicted.