MartinTalk.com

A steel-string guitar tuned to concert pitch endures a tension of 180 pounds (800 N) on the top of the guitar from the strings. The X-bracing system has been shown to be an efficient technique for preventing the top of the guitar from warping under this force. The braces are generally carved, scalloped and tuned in order to aid in the resonance and integrity of the guitar top, such capability being performed by skilled artisans and not readily reproducible by machine. This work is an important factor in determining the timbre of the guitar, and a major determinant in the observation that rarely do two guitars ever sound alike even though they are ostensibly identical in construction.