The natural resonant frequency of the violin case, or the so-called Helmholtz cavity resonant frequency, is around C in a specific standard size case, and the D string is located near this frequency, resulting in the longest residual sound. A slight nasal sound indicates that the resonance quality factor is too high. The so-called resonance quality factor is simply that the damping loss is too small. Damping loss means that the sound energy is converted into heat energy and disappears after excitation oscillation. The stronger the resonance of the violin case, the better. This will cause other frequencies to decay quickly, which is called poor balance. This can be understood by listening to the sound of an empty hot water bottle, as there are actually wideband sounds in the environment, but only the sound that resonates with the cavity of the hot water bottle is preserved, so we hear specific whining sounds. Therefore, it is not good for a string to be too long in relative extension.

There are two ways to deal with and correct this phenomenon: one is to adjust the piano code and sound column, but to scrape the panel and adjust the sound resonance characteristics of the soundboard, complementing the cavity resonance