Other String Instruments
String instruments or stringed instruments are musical instruments that produce sound from vibrating strings. In most string instruments, the vibrations are transmitted to the body of the instrument, which also vibrates, along with the air inside it. In the Hornbostel-Sachs scheme of musical instrument classification, used in organology, they are called chordophones. Common instruments in the string family include the violin, guitar, sitar, electric bass, viola, cello, harp, double bass, rebab, banjo, mandolin, ukulele, and bouzouki.
Types of other String Instruments
Contact points along the string
In bowed instruments, the bow is normally placed perpendicularly to the string, at a point half way between the end of the fingerboard and the bridge. However, different bow placements can be selected to change timbre. Application of the bow close to the bridge (known as sul ponticello) produces an intense, sometimes harsh sound, which acoustically emphasizes the upper harmonics. Bowing above the fingerboard (sul tasto) produces a purer tone with less overtone strength, emphasizing the fundamental, also known as flautando, since it sounds less reedy and more flute-like.
Similar timbral distinctions are also possible with plucked string instruments by selecting an appropriate plucking point, although the difference is perhaps more subtle.
In keyboard instruments, the contact point along the string (whether this be hammer, tangent, or plectrum) is a choice made by the instrument designer. Builders use a combination of experience and acoustic theory to establish the right set of contact points.
In harpsichords, often there are two sets of strings of equal length. These “choirs” usually differ in their plucking points. One choir has a “normal” plucking point, producing a canonical harpsichord sound; the other has a plucking point close to the bridge, producing a reedier “nasal” sound rich in upper harmonics.
Production of multiple notes
A string at a certain tension and length only produces one note, To produce multiple notes, string instruments use one of two methods. One is to add enough strings to cover the required range. The other is to provide a way to stop the strings along their length to shorten the part that vibrates. The piano and harp are examples of the former method, where each note on the instrument has its own string or course of multiple strings. (Many notes on a piano are strung with a “choir” of three strings tuned alike.) A guitar represents the second method—the player’s fingers push the string against the fingerboard to force the string over a fret and shorten the vibrating part.
Some zithers combine stoppable (melody) strings with a greater number of “open” harmony or chord strings. On instruments with stoppable strings, such as the violin or guitar, the player can shorten the vibrating length of the string, using their fingers directly (or more rarely through some mechanical device, as in the nyckelharpa and the hurdy-gurdy). Such instruments usually have a fingerboard attached to the neck of the instrument, that provides a hard flat surface athe player can stop the strings against. On some string instruments, the fingerboard has frets, raised ridges perpendicular to the strings, that stop the string at precise intervals, in which case the fingerboard is also called a fretboard.
Moving frets during performance is usually impractical. The bridges of a koto, on the other hand, may be moved by the player, occasionally in the course of a single piece of music. Many modern Western harps include levers, either directly moved by fingers (on Celtic harps) or controlled by foot pedals (on orchestral harps), to raise the pitch of individual strings by a fixed amount. The Middle Eastern zither, the qanun, is equipped with small levers called mandal that allow each course of multiple strings to be incrementally retuned “on the fly” while the instrument is being played. These levers raise or lower the pitch of the string course by a microtone, less than a half step.