A common variation of fan bracing on a classical guitar.

Being closely related to the lute, construction of the modern classical guitar grew out of that tradition. Classical guitars tend to have thinner tops and much lighter bracing than steel-string guitars, since nylon strings generate less tension across the soundboard.

The most commonly used bracing pattern is fan bracing. In this pattern, ribs "fan" out from the soundhole toward the back of the instrument. Actual placement of these ribs is key to the tone of the instrument. Luthiers have experimented with variations on this pattern with varying degrees of success.

Braces in traditional build guitars are made of the same material used for the guitar's top. That is, a spruce top guitar would use spruce braces. However, innovations in this area continue as well. For instance, Martin is now using a hybrid bracing system that combines an A-frame with an X-pattern for their 16 series guitars. They are also using wood composites for the X-bracing in the DX series. As a matter of fact, the DX series features only an X-shape as the bracing with no additional braces anywhere on the top. This is due the inordinate strength of the wood composite.

Other builders are going a step further. Garrison, Rainsong, and CA guitars all use a carbon composite for their bracing. The carbon is lighter than wood and tends to allow the top to vibrate more freely as a result. Garrison, by the way, builds a wood guitar using the carbon braces. Rainsong and CA build completely carbon composite guitars.