Material Considerations in Musical Strings
- PDF / 263,732 Bytes
- 2 Pages / 576 x 777.6 pts Page_size
- 47 Downloads / 216 Views
• An important property of vibrating strings is mechanical damping, i.e., energy loss after cessation of excitation. For plucked or struck strings, the amount of damping should be low to promote production of tones that decay slowly. Such low levels of damping in bowed strings, however, will interfere with production of sustained forced vibrations. The bowing process requires fairly quick suppression of asynchronous reflections from the end supports to the bowing point for precise control and good tone quality. In this respect, gut is excellent for bowing, but too highly damped for sustained tones on modern plucked or keyboard instruments, although appropriate for reproductions of ancient instruments. • A final consideration in any toneand made as short as acoustic power de- producing oscillator is frequency stabilmands will allow. The last condition is ity. Intonation is a constant struggle for important because the available power even the best musicians. In fretless (which translates to loudness) is a func- instrument? of the violin family, some tion of the total vibrating mass and its adjustment of finger position can comamplitude. A moment's thought will re- pensate for frequency drift during perveal that the ideal string material has a formance. Harpists or guitar players have no such option. Therefore, the use high ratio of tensile strength to density. of gut in such instruments was abandoned as soon as more stable materials Gut Strings The ancient Greeks had such a mate- became available. The frequency drift in rial; they called it chorde, a word that has gut, due to tension changes, has two today a pleasant association with music, components: long-term creep and immebut actually was the term for the intes- diate sensitivity to moisture. Under tentines of sheep. Our present-day word for sion, gut continues to lengthen over its the same material, which is still in use, is comparatively short useful life, although the less aesthetic but more descriptive at a sharply decreasing rate with time. word gut. The process of opening, clean- Increase of length with humidity is reing, slitting, twisting, and drying the versible, and never ends. In fact, a strand raw animal tissue is too unpleasant to of gut is used as the sensing element in dwell upon, but the resulting string ma- some hygrometers. terial, with a tensile strength of about 275 MPa and a density of 1.2 g/cm3 was Metal Wire and Windings the best available for thousands of years. Sometime late in the 15th century, a Gut has other properties, desirable and profound improvement in strings came otherwise, that affect its performance in about as a result of the availability of musical instruments: drawn wire in long lengths and small di• Because of its low density, plain-gut ameters. Ductile metals such as alloys of strings with sufficient tension to produce silver and/or copper were used to inadequate power at low frequencies have crease the unit mass of gut strings by to be very long, very fat, or both. This is simply wrapping them with closely not a great d
Data Loading...
