The bridge of mainly stringed instruments is where the strings rest between the nut and the tailpiece. There are many aspects of the bridge that need to be considered when cutting and fitting one onto an instrument. If any of the aspects is either overlooked or left out then you will likely experience one of many possible problems. Structure or sonic.
Depending on who cut it and where they take their influence from, there are a few ‘styles’ that may be observed. For example; as a rule French cut bridges will be perpendicular to the top of the instrument at the back of it (facing the tail piece), The front of the bridge (facing the fingerboard) is perpendicular according to the English cut and in some cases, which seems most logical to me is to cut it in a tee pee so that adjusting the bridge becomes easier to set to the instrument.
The quality of wood used to make bridges is also of great importance and has a noticeable influence on the sound and responsiveness when playing.
Below there are a few examples of how to detect if the cut of your bridge has problems that influence the durability, playability or sound of your instrument:
- If the feet of the bridge are not cut flush to the table (top) of the instrument then there will be a loss of frequency transfer which may dull either or both sound and responsiveness.
- If the feet are cut out of square with one another so that they warp if looked at over the level of their surfaces then the bridge will likely stand crooked with either of the sides warping forward and the other backward.
- When the feet are cut with an incorrect angle this will cause the bridge to lean backward or forward. Typically the bridge will bend forward if the feet are cut with a forward leaning angle causing the bridge to bend in the middle of it and if it is not kept as straight as possible with constant adjustment it will eventually break there. In the case where it is leaning backward, after a while, it will start looking a bit like a wind surfer’s sail.
- If the bridge is cut too thick it will stifle the sound and responsiveness.
- Too thin will make the sound unstable and/or shrill and the bridge weak.
- Often when cutting a bridge it needs cutting on both sides so if one is not aware of over cutting on any one of the four ‘corners’ at the top of the bridge then it is possible to cut a warp into the line that the strings rest on. This would mean that even with constant adjustment of the bridge it will always return to its cut position.
- In some cases when the wood is soft and/or of poor quality the strings cut into the bridge over time and cause the strings to become to close to the finger board. This may happen with a good bridge as well, although, mostly under the E string if there is no protective measure there to help prevent this or a piece of tubing on the E string to stop it from direct contact with the wood.
- If the bridge is cut too high in relation to the fingerboard it will be rather uncomfortable to play the instrument with the strings high above the surface … you will then need to really press down for each note meaning that fast playing will become near impossible. Of course, too low will be super comfortable but will more than likely buzz!
- By adding a bit of graphite in the string tracks on the bridge you will help arrest the forward bending although it is still necessary to check and adjust from time to time.
- If you notice that the E and/or A are cutting into the bridge you can either ask your Luthier to put a piece of partridge there or you can lift the string and put a tiny dot of super glue there to help strengthen the wood enough to stop it from being cut through.
- Every few tunings it is wise to look at the bridge from the side of the instrument to see if it is either leaning forward or back and adjust it accordingly.