String instrument: Encyclopedia II - String instrument - Contact points along the string

String instrument - 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 thin, "breathy" sound, emphasizing the fundamental frequency.

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 "nasal" sound rich in upper harmonics.

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