Violin making and maintenance

Sound post adjustment
Main article: Sound post

The position of the sound post inside the violin is critical, and moving it by very small amounts can make a substantial difference in the sound quality and loudness of an instrument. Soundpost adjustment is as much art as science, depending on the ears, experience, structural sense, and sensitive touch of the luthier. Moving the sound post has very complex consequences on the sound; in the end, it is the ear of the person doing the adjusting that determines the desired location of the post.

As a rough guide of how the sound post influences the sound output of the violin there are a few positions that can help find the right spot:

If the sound is too thin and shrill, the post may be too near the f hole or too tight or possibly the post is too thin. If the sound is weak and there is a loss of power (especially on the lower register), the post may be too near the center of the instrument. If the sound is chocked, the post may be to near the bridge foot or under it. If there is a loss of overall power and tone, the post may be too far behind the bridge or possibly the post is too thick.