Guitar It is flat on classical guitars and slightly curved crosswise on acoustic and electric guitars. The curvature of the fretboard is measured by the fretboard radius, which is the radius of a hypothetical circle of which the fretboard's surface constitutes a segment. The smaller the fretboard radius, the more noticeably curved the fretboard is. Most modern guitars feature a 12" neck radius, while older guitars from the 1960s and 1970s usually feature a 6-8" neck radius. Pinching a string against a fret on fretboard effectively shortens the vibrating length of the string, producing a higher pitch. Fretboards are most commonly
Ten-string guitar has a single neck and allows all strings to be fretted. While the six-string classical guitar remains the standard and most common instrument, since 1963 ten-string guitars in similar configuration to the original Ramírez have been adopted by many classical guitarists and produced by several first-class luthiers, using both Yepes' original tuning and others. The Halo Guitars XSI is a solid body ten-string guitar with ten individual steel strings, two EMG ten-string pickups, and a Kahler ten-string tremolo bridge. XSI is an acronym for Extended Scale Instrument. Halo Guitars tunes the XSI from low to high as follows: A+D+G+C+F-B♭-E♭-A♭-C-F. Agile