The nut of a
string instrument is a small piece of hard material which supports the strings at their top end (the end closest to the tuning pegs or machines). The nut has two functions: to hold the string in place and mark the start of the vibrating part of the string, and to set the spacing of the strings across the neck. Along with the
bridge, the nut defines the vibrating lengths (scale lengths) of the open strings.
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