音柱主要功能為支撐面板與傳遞面板的振動至背板，雖然它只占小提琴中的一小部分，但稍微改變它的外形或擺放位置，音色皆會產生變化。本文利用有限元素軟體ANSYS模擬小提琴的振動，分析模態圖以及驅動點導納圖。首先探討有音柱與無音柱的差別，發現無音柱會使聲音變低沉且響度變弱。第二，探討給予琴橋不同位置施力的差異，發現在琴橋兩端(G點或E點)所受到的驅動效率較高。第三，改變音柱的直徑大小與外形，發現音柱變細會使音質較鬆，音柱變粗使音質變硬，音柱改成與原截面積相同的中空圓柱型結構與音柱變粗結果相似。最後，探討音柱與面板背板間的角度問題，發現往X方向傾斜的影響會比往Y方向傾斜的影響大。

The functions of sound-post in a violin structure are that it can support the top plate and transfer the vibration motions from top plate to back plate. Although it is a small element in the violin, the timbre will be significantly changed when the sound-post is slightly changed such as its appearance or position. In this paper, we use finite element analysis to simulate the violin vibration and analyze the mode vibration pattern and driving point admittance pattern.
First, the necessity of the sound-post will be studied. The results show that the lower tone and weaker tonal strength are observed when the sound-post is removed. Secondly, after driving different points of bridge, the higher efficiency occurs at points G and E. Thirdly, the diameter and appearance of sound-post are changed to evaluate the tone. It shows that smaller sound-post induce looser tone and larger sound-post induce harder tone. If the geometry of the sound-post is changed to a hollow cylinder with same cross-sectional area, the same tendency is observed as the sound-post is larger. Finally, the effects of the angle between the axial direction of the sound-post and the horizontal plane of the top plate are investigated.

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