Guitar Frets are laid out to accomplish an equal tempered division of the octave. Each set of twelve frets represents an octave. The twelfth fret divides the scale length exactly into two halves, and the 24th fret position divides one of those halves in half again. The ratio of the spacing of two consecutive frets is formula_1 (twelfth root of two). In practice, luthiers determine fret positions using the constant 17.817—an approximation to 1/(1-1/formula_1). If the nth fret is a distance x from the bridge, then the distance from the (n+1)th fret to the bridge is x-(x/17.817). Frets are available in
Vibrato systems for guitar An advantage or disadvantage, depending on taste, is string resonance audible at several fret positions where a simple relation exists between the length to the fret and the string length behind the bridge (for instance 48:12 = 4:1). At those positions, a high overtone rises in volume. This becomes clearer with an over-driven guitar sound. The overtone might sound odd, but it still has a harmonic relation to the note, so is not out of tune related to the open string. For staccato playing, it can be annoying. Muting the strings behind the bridge with felt or other material solves