Modified Wood of Black Locust - Alternative to Honduran Rosewood in the Production of Xylophones

Abstract

Traditionally, exotic hardwoods are used for the production of xylophone or concert marimba. Mainly the Honduran rosewood shows the optimal properties (high density, high modulus of elasticity, speed of sound, hardness, low damping) considering the required acoustic quality of the xylophone. The Honduran rosewood is listed in CITES Appendix II, therefore it is necessary to look for possibilities of its replacement by other wood species. However, the density, hardness and strength properties of the European wood species are rated less than Honduran rosewood. Therefore it is clear that there is a need to search for alternative of exotic wood. Our research indicates that the Honduran rosewood can be replaced by European wood species; however it is necessary to modify their properties. As convenient modication of domestic wood species appear: mechanical modication (densication), thermal modication or a combination of these two methods. Thus we can obtain wood with properties similar to the properties of exotic wood. The study presents the comparison of physical and acoustical characteristics of modied wood of Black locust with the characteristics of the Honduran rosewood. Also, the sound quality of xylophone made from Black locust wood before and after modication was investigated.

Acoustic properties of Norway spruce wood modified with staining fungus (Sydowia polyspora)

“…According to numerous studies, thermally modified spruce wood meets the requirements for the production of musical instruments (Pfriem et al 2007;Korkut et al 2008;Košúth et al 2012;Puszyński and Warda 2014;Danihelová et al 2015). The hightemperature treatment of wood (180 °C to 220 °C) causes a decrease in its density, which beneficially increases the sound radiation coefficient in connection with an increase in the sound speed in the wood (Schwarze and Schubert 2011).…”

Avaliação das propriedades acústicas de mogno africano (Khaya ivorensis) submetido a tratamento térmico em estufa e autoclave

“…Alto E/ρ representa maior eficiência de vibração da madeira [9]. A atenuação acústica é a característica física que representa a capacidade do material de dissipar a energia acústica, sabe-se que quanto menor for esse fator, melhor será a qualidade acústica da madeira [9,11,13].…”

“…DANIHELOVÁ et al [13] utilizaram processo de tratamento hidrotérmico semelhante ao utilizado pela Associação ThermoWood ® , em madeira de Robinia pseudoacacia. Observaram aumento nos valores dos módulos de elasticidade, redução da densidade, também observado por ZHU et al [8] em madeiras de Picea jezoensis submetidas a tratamentos com nitrogênio (N 2 ).…”

Thermal Modification of Spruce and Maple Wood for Special Wood Products

“…The aim of wood modification is to achieve the required properties of wood for musical instruments. Mechanical modification (densification) of wood, thermal modification, or their combination, appear to be suitable modifications of wood for musical instruments [ 6 , 7 , 8 , 9 , 10 , 11 , 12 ]. Similarly, the biological modification of wood with wood-staining fungi or wood-destroying fungi can be used to modify the relevant properties [ 13 , 14 , 15 ].…”

“…The darker shade of wood color is welcome for some kinds of musical instruments (marimba, xylophone, guitar, etc. ); however, this is provided that the wood has the required physical and acoustic properties in addition to color [ 6 , 24 , 25 ].…”