Sound waves are part of a chain of events that are necessary for people to hear musical tones. In violin playing, vibrations are transmitted from vibrating strings that eventually travel through the air to the ear drum of a listener. The type of sound wave produced by violins is caused by these vibrations and the instrument itself.
To start sound, a violinist normally uses a bow with stretched horse hair to literally scrape a string to vibrate. The A-string, one of four on the instrument, is tuned to vibrate 440 times per second. This rate of speed causes the string to appear as a blur to the human eye.
As a string is set into vibration, it vibrates as a whole from one fixed end to the other. Pitch, the highness or lowness of a tone, is determined by the frequency of the fundamental. At the same time, the string divides itself into shorter lengths of vibrations that produce a series of overtones. These overtones, however faint, determine the distinctive timbre, or tone quality of the instrument. Overtones of the violin produce jagged sound wave forms which result in a sharper sound compared to more rounded wave forms of a guitar.
Vibrations from strings need to be amplified in order to be heard easily. Without the wooden parts of the violin only faint sounds would be heard. Vibrations are transmitted through a bridge, down a sound post and into the body of the violin. This allows the entire instrument to resonate, which causes a louder, more satisfying, sound output.
Travelling Longitudinal Sound Waves
Sound waves from a violin travel in all directions. This can be seen when a pebble is dropped in a pond -- crests and troughs of water waves radiate from the centre. Vibrations from the violin cause rapid variations of air pressure on the molecular level, in which there are cycles of compressed areas alternating with those spread out more thinly. Longitudinal is a term used to describe the push-pull effect in air rather than an up-down motion observed in water waves.