Making the soundboard

The guitar soundboard, often referred to just as the “top”, is the most critical component of the guitar in relation to its tone and projection.  There are many factors in a top that will affect its sound: bracing pattern, wood choice, and component thicknesses.

First, regarding bracing it is important to remember that bracing serves at least three functions: 1) strength to support the tension of the strings, 2) sound transmission, and 3) the creation of areas of stiffness and elasticity.  While there are presently a variety of bracing designs ranging from traditional to experimental, it is important to remember that each family of bracing designs will come with its own characteristic strengths and weaknesses.  In addition, it must be remembered that the soundboard vibrates as a unified whole, and hence each single element must be adjusted and “tuned” with consideration as to how this tuning (thinning) will affect the completed soundboard.

For example, in order to enhance the bass sound, thinner and or longer bracing is required.  But, thinning a brace also lessens the sound transmission of said brace, and reduces its ability to support treble notes and the harmonic overtones of bass notes.

In addition to bracing, the luthier must be aware of wood varieties and their inherent sonic and elastic properties.  For example, it is agreed that cedar generally produces a rounder and less focused sound than spruce, and while cedar tends to sound fuller in a small room, it does not tend to project as strongly as spruce in a large concert hall.  However, there are several famous guitar builders who have had great success with cedar in building wonderfully powerful and focused concert guitars by using a bracing system that balances and rectifies the characteristics of cedar as a top wood.

Hence, in order to create a soundboard that is successful in balancing bass and treble response, that at the same time has strong sustain and harmonics, the artisan is required to craft the various individual components into a balanced and unified whole.

Photos show a Canadian Englemann spruce soundboard braced with Canadian sitka spruce.

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