Tonal adjustments are normally carried out by modifiyng the “set up”, which consists of:
bridge, soundpost, fingerboard, neck angle, top nut, saddle, tailpiece, tailgut, chinrest, adjusters, pegs and strings.
Each one of these parts affect the sound, some dramatically, others subtly.
The great majority of the instruments that come to my workshop can be improved with some changes in the set-up. It is very easy for an instrument to sound weak and hollow with a poorly fit soundpost, muted or subdue with a bridge that is too thick, unplayable with an action (string height) that is too high or too low or untunable because the pegs don’t work, the list goes on. By rectifying all the mechanical parts of the set up, it will be more comfortable and playing will be easier.
Secondly, the character of the sound can be partly changed, or just tweaked, according to your instrument needs and your need as a player. The instrument might need more support,more focus or power, or it might lack projection, responsiveness or colour; the player might have big fingers or small hands, his playing style might be very powerful and energetic, or more sweet and mellow. All these individual characteristics can be matched in order to optimize your specific violin with you as an individual player.
I really enjoy this kind of work. It is very interesting as it goes right into how an instrument really works; I also find it extremely rewarding, as you can achieve massive improvements in a very short time.