String instrument: Encyclopedia II - String instrument - Types of string instruments

String instrument - Types of string instruments

String instruments are usually categorized by the technique used to produce sound. In order for a string instrument to produce sound, its string or strings must vibrate. There are three common ways to initiate vibration.

String instrument - Plucking

Instruments such as the guitar, kora and sitar are plucked, either by a finger or thumb, or by some other device such as a plectrum.

String instrument - Bowing

Instruments like the cello and rebec are usually played by drawing a bow across the strings. All instruments in the viol and violin families fall into this category. Occasionally instruments which are normally bowed are plucked (this is known as pizzicato) instead, and instruments normally plucked are also bowed (for example, Jimmy Page of Led Zeppelin sometimes played the electric guitar this way using a violin bow, and more recently Jón Þór (Jónsi) Birgisson, singer and guitar player of the Icelandic band Sigur Rós has made use of the technique).

String instrument - Striking

The third common method of sound production in stringed instruments is to strike the string with a hammer. By far the most well-known instrument to use this method is the piano, where the hammers are controlled by a mechanical action; another example is the hammered dulcimer, where the player herself wields the hammers. It should be noted that the piano is often considered a percussion instrument, since sound production through struck blows defines this instrument family; the proclamation that the piano is a percussion instrument has at times served as rhetoric for composers who relished sharp percussive effects.

A variant of the hammering method is found in the clavichord: a brass tangent touches the string and presses it to a hard surface, inducing vibration. This is a very inefficient method of sound production, thus clavichords have a very soft tone. The maneuver can also be executed with a finger on plucked and bowed instruments, where it gives equally soft results.

String instrument - Other methods

The aeolian harp employs a very unusual method of sound production: the strings are excited by the movement of the air.

Some string instruments have keyboards attached which are manipulated by the player, meaning she does not have to pay attention to the strings directly. The most familiar example is the piano, where the keys control the felt hammers by means of a complex mechanical action. Other string instruments with a keyboard include the clavichord (where the strings are struck by tangents), and the harpsichord (where the strings are plucked by tiny plectra).

With these keyboard instruments too, the strings are occasionally plucked or bowed by hand. Composers such as Henry Cowell wrote music which asks for the player to reach inside the piano and pluck the strings directly, or to "bow" them with bow hair wrapped around the strings.

Adapted from the Wikipedia article "Types of string instruments", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki