Graduating the Top of a Joshua Alexander French Guitar
The top of the classical guitar is most commonly made of solid book-matched spruce or cedar because of their high strength-to-weight ratio.
Sitka Spruce has a high strength-to-weight ratio. It is an ideal soundboard, especially for aggressive playing styles and/or large instrument sizes. Spruce ages well, is harder and possibly more durable than cedar, gives a crisp, more focused sound, and provides excellent treble response. Spruce tops require a longer break-in time than cedar. Light blonde in color.
Engleman Spruce is not as stiff as Sitka, but popular because of its appearance. Works well on smaller bodied instruments because of its lower stiffness. It has a beautiful sheen much like the European spruces with less contrast between its growth rings. Usually looks whiter than Sitka.
Western Red Cedar is not as stiff as the spruces, which makes it ideal for lower tension or smaller bodied instruments. It has a warmer tone with excellent bass response and will produce a mature tonal quality more quickly than a spruce top. Color varies from light reddish to a light chocolate brown.
Guitar top by Pimentel & Sons
A soundboard has two purposes on a guitar, one as a stable anchor for the strings, and the other as the vibrating unit with which to move air (produce sound). This dual purpose makes stiffness such an important quality. Too much stiffness will dampen the tone. With too little stiffness the top will distort. Along with strength, wood is chosen for its appearance and consistency.
A Cedar Top
Other qualities desired in a soundboard:
Grain: The grain should be straight, parallel and consistent with tight annual rings. These characteristics add stiffness which helps the builder have more control in the final outcome of a guitar top.
A Bearclaw Top by Rodriguez Guitars
Figure: Some tops have a “silky” appearance (Soft grainy lines running perpendicular to the top). Some makers like this and some don’t. If silk is present it should be present throughout the entire top. Another feature up and coming on classical guitar tops is “Bearclaw”. Bearclaw (like it sounds) looks like a bear used a tree to sharpen its claws and left nonsymmetrical small waves in the grain. Once considered inferior because of appearance, it’s now sought after because of its increase in density. Bearclaw tops have become popular on bluegrass guitars and may soon be seen as an alternative in Classical Guitar construction.
Color: A consistent and even color is desirable for higher grade guitars.
A Top by Oberg Guitars
Guitar makers use a grading system to differentiate the quality in wood.
- Master Grade is awarded to one in a hundred (or more) tops (very rare). Master Grade is the best of the best.
- AAA is the second highest awarded for stiffness across the top, straight grain, quarter sawn, even color and consistent annular ring spacing.
- AA is given for slightly wider and/or inconsistent ring spacing or mild color variations.
- A is given for lack of stiffness, inconsistent ring spacing with visible cosmetic flaws.
Inspecting a Top at Schneider and Son
There are many factors that contribute to the overall sound of the guitar top. Factors can include internal inner braces, thickness of material, pattern and shape of the instrument, type of finish, and type of strings, but a good piece of wood is a good start.
Processing Cedar Blocks for Soundboards at Jose Oribe Guitars
The Back & Sides...
The Backs & Sides of Jose Oribe
Traditionally the Back & Sides of the Classical Guitar were made of solid book-matched Rosewood, Mahogany or Cypress, but today's builders have opened their horizons to a wide variety of choices. Also see Wood Choices for the Back & Sides of a Classical Guitar and Alternative Wood Choices for the Classical Guitar.
Book-Matching a Back.
A - Slab of wood
B - Split in half
C - Pivot one halve
D - Continue pivot
Macassar Ebony Book-Matched before Jointing.
The Bent Sides of Oberg Guitars