Compound radius

The fingerboard (also known as a fretboard on fretted instruments) is an important component of most stringed instruments. It is a thin, long strip of material, usually wood, that is laminated to the front of the neck of an instrument. The strings run over the fingerboard, between the nut and bridge. To play the instrument, a musician presses strings down to the fingerboard to change the vibrating length, changing the pitch. This is called stopping the strings. Depending on the instrument and the style of music, the musician may pluck, strum or bow one or more strings with the hand that is not fretting the notes. On some instruments, notes can be sounded by the fretting hand alone, such as with hammer ons, an electric guitar technique.

The word "fingerboard" in other languages sometimes occurs in musical directions. In particular, the direction sul tasto (Ital., also sulla tastiera, Fr. sur la touche, G. am Griffbrett) for bowed string instruments to play with the bow above the fingerboard. This reduces the prominence of upper harmonics, giving a more ethereal tone.

A fingerboard may be fretted, having raised strips of hard material perpendicular to the strings, which the player presses the strings against to stop the strings. On modern guitars, frets are typically made of metal. Frets let the player stop the string consistently in the same place, which enables the musician to play notes with the correct intonation. As well, frets do not dampen string vibrations as much as fingers alone on an unfretted fingerboard. Frets may be fixed, as on a guitar or mandolin, or movable, as on a lute. Fingerboards may also be unfretted, as they usually are on bowed instruments, where damping by the finger is of little consequence because of the sustained stimulation of the strings by the bow. Unfretted fingerboards allow a musician more control over subtle changes in pitch than fretted boards, but are generally considered harder to master. Fingerboards may also be, though uncommon, a hybrid of these two. Such a construction is seen on the sitar, where arched frets attach at the edges of a smooth fingerboard; unfrettable strings run inside the frets, while frettable ones run outside. The fret arches are sufficiently high that the exterior strings can be fretted without making the finger making contact with the interior strings and Frets may be marked by inlays to make navigating the fingerboard easier.

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