Construction of the Violin

By Phillip Foltz

History of Violin Making

• Violins began developing in the 15th century.

• The violin we know today developed in the 16th century.

• The viola and cello each were developed from the violin.

Famous Violin Makers

• The most famous violin makers are probably the Stradivari family, especially Antonio Stradivari. His work continues to be studied today, looking for the secrets of his remarkable instruments. He made in excess of 1000 instruments prior to his death in 1737. Approximately 650 of those still exist.

Other famous makers

• Amati

• Stainer

• Guarneri

• Gagliano

• The quality of the violinist’s performance can never be better than the quality of the instrument being played. That quality begins to be determined by the selection of the wood for the violin, before the instrument is even being formed.

• Ideal kinds of wood for different parts have been determined largely through trial and error.

• Today’s best choices for violinmakers:

Front, soundpost, bassbar: spruce

Back, sides and neck: maple

Fingerboard: ebony

Selecting the Kinds of Wood

Selecting the Pieces of Wood

• Challenge: balancing density and stiffness to maximize the vibrations of the wood while maintaining sufficient strength

• Solution: the front is created primarily for vibration and sound quality while the back adds the needed strength without negatively impacting the sound

Density of the Top

• For the spruce top, the ideal density is between .36 and .39 g/cc. This yields a top whose stiffness is high in comparison to its density. As the maker thins the wood, the stiffness goes down and therefore its frequency goes down.

• Lower density means less mass which means easier vibrations.

Density of the Back

• For the maple back, sides and neck, the ideal density is between .56 and .60 g/cc. This yields a back which is stiffer than the front, with a greater density which lowers the frequency, with the maple hardwood adding strength to the instrument.

Knowing Where to Carve

• Trial and error has yielded much information for violin makers (aka luthiers) to use as general guidelines. However, each piece has its own characteristics and will vary some from the generalizations passed through generations of violin making. The best instruments come from makers who understand how to carve each specific piece.

Listening to the Wood

• Many violin makers listen to the resonant frequencies of the wood as they carve it. Different densities, thicknesses, and shapes yield distinctly different resonant frequencies.

• As the violin maker carves away wood, the resonant frequencies lower. This permits the instrument to be adjusted to the maker’s target frequency.

Using Chlodni Patterns

• Many violin makers use Chlodni patterns to determine carving targets. By sprinkling glitter on the workpiece, then subjecting it to various resonant frequencies, the maker can determine where the wood needs more vibration. This need determines where and how much the maker should carve.

Chlodni pattern: front, Mode 1 (before)

Mode 1 (after)

Mode 2 (before)

Mode 2 (after)

Mode 5 (before)

Mode 5 (after)

Mode 1 (before with bassbar)

Mode 1 (after with bassbar)

Mode 2 (before with bassbar)

Mode 2 (after with bassbar)

Mode 5 (before with bassbar)

Mode 5 (after with bassbar)

Helmholtz Resonance

• An additional concern for the violin maker is the air resonance within the violin, aka the Helmholtz resonance. The violin maker adjusts this by reducing the height of the sides as necessary. Without attempting to do a detailed analysis of this feature, I will demonstrate how the violin maker can check this and how it varies.

Summary

The creation of a quality instrument demands:

•the right types of wood

•shaped to the right thicknesses in the right places

and

•assembled to create the right air chamber.