Fitting the bridge is for the sound of an instrument very important.
After all, this small piece of wood is the point at which the strings'
vibrations are carried to the instruments body. Normally maple is the
material used, as it exhibits pronounced medullary rays.
Various raw castings for bridges are available in violin building.
Several firms in Europe have a very long tradition when it comes to this
craft. Two important companies worth mentioning are the French bridge
manufacturers Aubert in Mirecourt and Despieau, the first manufacturer
to use laser cutting techniques. I would also like to mention the German
companies Stamm, Schuster and Teller, although when it comes to
high-quality instruments, we prefer the Deluxe bridge model from Aubert
in France. When it comes to historical or particularly "delicate" cases,
we build our own bridges with raw castings in our own workshop. In this
case the bridge is designed exactly for that instrument only.
What is important to consider about the bridge?
First of all, one should consider what the reason for needing a new bridge could be.
Do the reasons behind changing a bridge have to do more with tonal
questions or with playing technique? If it is the latter, and the
instruments sound with the old bridge is very good, then one should use
wood which exhibits similar sound distinction and stability qualities to
that of the old bridge.
If a new bridge is to improve the sound quality of an instrument, these
tonal changes can be achieved by using a harder or softer type of wood.
But also the arrangement of the bridge cuttings can later have a great
affect upon the sound of the instrument.
First some general information:
- The width of the bridge should not exceed the width of the upper f balls.
- The bridge should be in the acoustic center, on the imagined line between both f-hole notches.
- The bridge should lie exactly aligned to the fingerboard in
order that both the highest and lowest strings have the same distance to
the fingerboard's edge.
- The violin's bass bridge foot should protrude about 1 to 2mm over the bassbar.
(With violas it should be about 2 to 3mm, with cellos about 3 to 5mm, depending upon the instrument's size in each case.)
- The bridge should sit exactly between the f-hole notches
When cutting out the bridge in violin making, the following tools are needed:
- 2 woodcarving knives. Normally we make the handles ourselves so
that they are in the hand perfectly. For the bridge we take a wide one
to adjust the belly's feet und a narrow one to deepen the openings.
- A small plane to increase the bridge's strength,
- a flat file and smaller round files,
- a sandpaper file for final smothing and
- a pattern for rounding the bridge are used.
The first task is planing the bridge feet for strength.
For a violin bridge this represents approximately 4.5mm.
The next task is adjusting the bridge feet to the belly curvature.
This demands extremely precise skill as the accuracy of the fit is
decisive when it comes to optimal vibration propagation.
Somewhat more has to be cut away here. This is down with the "big" woodcarving knife as seen in the tool photo.
This type of cutting requires sharp tools and a calm and able hand.
The feet must be adjusted in such a way that the reverse side of the
bridge (the part that shows to the tailpiece) stands at a right angle to
mathematical base area. Being that the front of the bridge is arched,
it appears is if the bridge is slightly inclined toward the tailpiece.
The cut-outs, the feet and their connecting bow (also referred to as
bridge in violin making) are trimmed with the narrow woodcarving knife.
The size and the form of these cut-outs, as well as the forming of the
feet, have a significant effect upon the acoustic properties of the
bridge and, therefore, the instrument.
One the bridge fits perfectly within the belly curvature, the bridge rounding and height can be determined.
The bridge rounding must be formed in such a way that lets every
string be easily and individually bowed without making fast changes to
other strings difficult.
The height of the bridge is individually adjusted to match the
playing qualities and string selection of the given musician. Playing
solo demands just as high a lateral position as do using gut strings,
for instance, which display a higher vibration amplitude as synthetic or
steel core strings.
The thickness of the bridge also brings variation to the tone of the
instrument. One only needs to think of the tonal effect muting has,
which represents nothing other than a complete raising of the upper part
of the bridge.
The arching at the front of the bridge, the part that faces the fingerboard, is taken care of with the finger plane.
Traces of the planing are removed with a precision file and then the bridge is aligned.
This picture shows only the fitting
accuracy of the brigde without string pressure! Even without tension of
the brigde feets must adjust all-about. The cut-outs in the brigde must
created individually according to the instrument´s sound condition. Should
the bridge move during tuning or incline in one direction or
the other when new strings are wound, place it carefully back in the
Do you have questions about this subject?
You have two ways of stilling your curiosity:
You can place your question in our forum, then others who interested in the question might get something out of it, or you ask us directly using our contact form.