Stabilization of Acoustical Properties of Wooden Musical Instruments By Acetylation


  • Hiroyuki Yano
  • Misato Norimoto
  • Roger M. Rowell


Dimensional stabilization, acoustical properties, acetylation, specific dynamic Young's modulus, internal friction


Because variable humidity affects the acoustic properties of wood, manufacturers of wood instruments must minimize dimensional changes caused by the absorption of water. Acetylation reduces the moisture content of the cell wall, thereby increasing the stability of the acoustic and dimensional properties of wood under conditions of changing humidity. The acetylation of wood slightly reduces sound velocity (by about 5%) and also reduces sound absorption when compared to unreacted wood. Hence, acetylation does not change the acoustic converting efficiency.


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