Institute of Musicology, University of Hamburg, Neue Rabenstrasse 13, 20354 Hamburg, Germany.
J Acoust Soc Am. 2012 Jan;131(1):819-28. doi: 10.1121/1.3651096.
Two recently built vihuelas, quasi-replicas of the Spanish Renaissance guitar, one with a small body and one sound hole and one with a large body with five sound holes, together with a classical guitar are investigated. Frequency dependent radiation strengths are measured using a 128 microphone array, back-propagating the frequency dependent sound field upon the body surface. All three instruments have a strong sound hole radiation within the low frequency range. Here the five tone holes vihuela has a much wider frequency region of strong sound hole radiation up to about 500 Hz, whereas the single hole instruments only have strong sound hole radiations up to about 300 Hz due to the enlarged radiation area of the sound holes. The strong broadband radiation of the five sound hole vihuela up to about 500 Hz is also caused by the sound hole phases, showing very consistent in-phase relations up to this frequency range. Also the radiation strength of the sound holes placed nearer to the center of the sound box are much stronger than those near the ribs, pointing to a strong position dependency of sound hole to radiation strength. The Helmholtz resonance frequency of the five sound hole vihuela is influenced by this difference in radiation strength but not by the rosettas, which only have a slight effect on the Helmholtz frequency.
两把最近制作的维乌埃拉琴，西班牙文艺复兴时期吉他的准复制品，一把是小琴体单音孔，另一把是大琴体五音孔，再加上一把古典吉他，都进行了研究。使用 128 个麦克风阵列测量了频率相关的辐射强度，通过在体表面反向传播频率相关的声场。所有三种乐器在低频范围内都有很强的音孔辐射。在这里，五音孔维乌埃拉在大约 500 Hz 的频率范围内有更宽的强音孔辐射区域，而单音孔乐器由于音孔的辐射面积增大，只有大约 300 Hz 的强音孔辐射。五音孔维乌埃拉在大约 500 Hz 的强宽带辐射也是由于音孔相位造成的，在这个频率范围内显示出非常一致的同相关系。音孔放置在靠近音箱中心的位置的辐射强度也比靠近肋骨的位置强很多，这表明音孔到辐射强度的位置依赖性很强。五音孔维乌埃拉的亥姆霍兹共振频率受到这种辐射强度差异的影响，但罗塞塔（音孔周围的装饰结构）的影响很小，对亥姆霍兹频率只有轻微的影响。
