Investigation of the Acoustic Properties of Chemically Impregnated Kayu Malam Wood Used for Musical Instrument

Abstract

e chemical modification or impregnation through preparing the wood polymer composites (WPCs) can effectively reduce the hygroscopicity as well as can improve the acoustic properties of wood. On the other hand, a small amount of nanoclay into the chemical mixture can further improve the different properties of the WPCs through the preparation of wood polymer nanocomposites (WPNCs). Kayu Malam wood species with styrene (St), vinyl acetate (VA), and montmorillonite (MMT) nanoclay were used for the preparation of WPNCs. e acoustic properties such as specific dynamic Young's modulus (E d /γ), internal friction (Q −1 ), and acoustic conversion efficiency (ACE) of wood were examined using free-free flexural vibration. It was observed that the chemically impregnated wood composite showed a higher value of E d /γ than raw wood and the nanoclay-loaded wood nanocomposite showed the highest value. e reverse trend was observed in the case of Q −1. On the other hand, chemical impregnation has a minor effect on ACE of wood for musical instruments. e results suggested that the chemically impregnated Kayu Malam wood polymer nanocomposite (WPNC) is suitable for making soundboards of violin and guitar instruments to be played longer without losing tone quality.

Measurement and Analysis of the Vibration Responses of Piano Soundboards with Different Structures

“…[8,9]. Of course, some scholars are seeking optimization methods for soundboards, such as through chemical impregnation [10] or by conducting finite element simulations on the soundboard manufacturing process to find optimization solutions [11]. Scholars have sought the acoustic effects and influencing factors of pianos through designed models [12][13][14][15].…”

Dynamic Properties Of Wood Obtained By Frequency Resonance Technique And Dynamic Mechanical Analysis

“…Due to their high correlation with static moduli (r 5 0.82) (Karlinasary et al 2008), and with the modulus of rupture (r 5 0.90) (Hassan et al 2013), dynamic moduli of elasticity are used to predict the strength and stiffness of wood (Hein and Brancheriau 2018;Fern andez-Serrano and Villasante 2021), wood-based composites (Hamdan et al 2010;Wang et al 2012), and standing trees (Wang et al 2001;Mora et al 2009). Density (r) and dynamic moduli of elasticity are used to calculate the acoustic impedance and the sound radiation coefficient (Wegst 2006;Ahmed and Adamopoulos 2018), and (in combination with the damping coefficient tan d) to determine the acoustic conversion efficiency (Hossen et al 2018;Danihelov a et al 2019). All these vibro-acoustic parameters are used for the selection of quality material for musical instruments (Wegst 2006;Bucur 2016;Ahmed and Adamopoulos 2018;Hossen et al 2018;Tronchin et al 2020).…”

“…Density (r) and dynamic moduli of elasticity are used to calculate the acoustic impedance and the sound radiation coefficient (Wegst 2006;Ahmed and Adamopoulos 2018), and (in combination with the damping coefficient tan d) to determine the acoustic conversion efficiency (Hossen et al 2018;Danihelov a et al 2019). All these vibro-acoustic parameters are used for the selection of quality material for musical instruments (Wegst 2006;Bucur 2016;Ahmed and Adamopoulos 2018;Hossen et al 2018;Tronchin et al 2020). The dynamic parameters for the above-mentioned applications are determined using nondestructive tests (NDT) (Wang et al 2012).…”