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