An acoustical study of the qin

The qin (guqin, chi'in) is a seven-string zither of ancient lineage that is prominent in Chinese musical culture. The qin's history is intertwined with philosophy and folklore and its construction is replete with symbolism. The qin was associated with the Imperial aristocracy, and it remains an instrument of high culture. The qin is played with strings horizontal, and the soundbox is made in two halves; the front is usually carved out of paulownia and the back is a flat plate of catalpa. There are two sound holes in the back. It appears that no acoustical study of the qin has been published hitherto. This paper describes vibroacoustic measurements on five examples, the analysis of which reveals the qin's basic sound radiation mechanisms. At low frequencies the qin shows beam bending and torsional modes with some coupling to air in the cavity. At higher frequencies the radiation is dominated by a dense spectrum of mixed cavity and wood modes; the cavity modes are described by a one-dimensional transmission matrix model.