1. The degree of contact between the end face of the sound column and the piano board has a much greater impact on the timbre than whether the sound column is vertical or not. If the end face of the sound column is not handled properly, it will produce serious squeaking noise. A slight tilt of the sound column has no effect on the tone quality. When the end face of the sound column is difficult to handle seamlessly and has to consider the choice between closeness and verticality, the former should be chosen.

2. On the premise that the contact point between the upper end face of the sound column and the panel in all experiments is basically fixed (5mm behind the center of the right foot of the qin horse), and the lower end face of the sound column is in close contact with the qin board, and the tightness of the top pressure is basically the same, different end face treatment methods (inclined grinding in the same direction or inclined grinding in different directions) and multiple sound columns of different lengths are used for testing. When the sound column is slightly tilted within about 5 degrees, the tone has no effect at all. When the sound column continues to tilt to 5-10 degrees, the tone tends to become softer, appearing more natural in vibration and easier to pronounce than when it is rigidly vertical. When the sound column continues to tilt beyond 15 degrees, the volume becomes noticeably weaker and the pronunciation becomes slightly difficult. Of course, the results of this experiment contain the influence of the foot position of the sound column on the timbre.

3. Setting the contact point (landing point) between the end face of the violin column and the board at the solid and loose parts of the tiger skin pattern on the backboard seems to have a slight difference. The former is harder, while the latter is softer, but not obvious. However, setting the footrest on the solid wooden area with tiger skin pattern on the backboard produces a stable sound; Setting the footrest point on the loose wooden part of the tiger skin pattern on the backboard, the sound is a bit unstable, and the sound on the second day of the experiment is significantly different from that on the day of the experiment. This difference seems to be present in violins with wide tiger skin patterns on the backboard, but not in violins with fine tiger skin patterns on the backboard.

4. When installing the sound column, there is no significant difference in whether the annual rings on the end face of the sound column are perpendicular to those on the piano board. It seems to be installed vertically, slightly brighter, with a smooth thread installation, and softer.