It is extremely important for string instrument players to constantly monitor the bridge to make sure it remains straight and properly positioned, and that it has not been damaged by worn strings. This is critical for the instrument’s sound as well as to prevent deterioration of the bridge.
Assessing Bridge Position
The normal position for the bridge is directly between the inner nicks of the f-holes, centered between them so that the bridge is centered on the path of the fingerboard.
Check your violin’s bridge position by looking first down one side of the board and then down the other, noticing how the bridge lines up compared to the two sides. Since the position of the bridge can affect the tone of the instrument, sometimes a slightly different location than “normal” works better. Often, a maker will place tiny pinpricks in the varnish on either side of the bridge to indicate its optimal position. They will usually be very small and hard to see, appearing almost as tiny accidents. If there are no marks and a professional adjustment has resulted in an unconventional location for the bridge, note the proper spot relative to landmarks in the varnish and wood, and make sure the bridge stays where it was set.
With some instruments, one f-hole and its nicks is slightly higher on the instrument than the other; if this is the case, the bridge should be set perpendicular to the center line of the instrument, not on an imaginary line from one f-hole nick to the other.

From the side, the bridge should appear to tilt back a bit towards the tailpiece. A good test is to rest a business card on the G-string side c-bout edge and use it as a square, comparing the perpendicular edge of the card to the back side of the bridge. If the bridge is positioned at the proper angle, when the edge of the card is lined up with the back of the bridge top, the card edge should also line up with the bridge feet about one-fourth of the way from their back, indicating just a small backwards tilt (see illustration above).
Strings Come into Play
There’s one more thing that can happen to a bridge. Strings do wear out and if a winding is damaged, it can saw its way deeply into the bridge (or the nut for that matter) very quickly. Of course, by this time the sound quality of the string has long since deteriorated. Bad strings cannot always be detected by their appearance, so regular replacement (as often as every month for an active player) is a must. One of the easiest and most magical adjustments that many violins can get is a new set of strings, and this is an adjustment you can easily do at home.
