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
Eight-string guitar and six-string variants. The standard tuning (from low to high) is F#, B, E, A, D, G, B, E. Many prefer to tune the F# to a low E (E1), the same note as the lowest string on a four-string electric bass in standard tuning, and providing the guitar with a fuller sound by having three different E strings. Like the seven-string, the first mass-produced eight-string guitar was made by Ibanez guitars in Japan; the RG2228. The main design issue faced with an eight-string guitar is tuning stability with the lower strings. This is due to the neck being constructed