Nut (music)

A nut, on a stringed musical instrument, is a small piece of hard material that supports the strings at the end closest to the or scroll. The nut marks one end of the vibrating length of each open string, sets the spacing of the strings across the neck, and usually holds the strings at the proper height from the fingerboard. Along with the bridge, the nut defines the vibrating lengths (scale lengths) of the open strings.

Violin

Mandolin

Guitar

Erhu

Compensated nut on Music Man Bongo 5 bass guitar

The nut may be made of ebony, ivory, cow bone, brass, Corian or plastic, and is usually notched or grooved for the strings. The grooves are designed to lead the string from the fingerboard to the headstock or pegbox in a smooth curve, to prevent damage to the strings or their windings. Bowed string instruments in particular benefit from an application of soft pencil graphite in the notches of the nut, to preserve the delicate flat windings of their strings.

The word may have come from the German Nut (pronounced "noot"), meaning groove or slot. The nut, however, is called a ("saddle"; also Obersattel) in German, whereas the part of a guitar known as the saddle in English, the surface of the bridge on which the strings rest, is called a or Steg, in German. In French, the nut is known as a , which, like German, can also translate to mean saddle. The Italian term, capo tasto (or capotasto; "head of fretboard"), is the origin of the capo.

Not all string instruments have nuts as described:

String slots in a nut without a zero fret must be cut to the proper depth to make string height correct. Strings that are too low at the nut can buzz against the frets, and too high throws off intonation of fretted notes.

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Wikipedia