Hi there Cna someone please help me answer the following question? in string instruments, unlike most instruments, resonaces of the body of the instrument play no part in determining pitch. what role do these resonances play in a string instrument and how is disirable for them to be distributed in frequency? Thanks in advance phyiscs_06er
Hm... I'll make a small attempt here... The body's resonance contributes to the quality of sound and also loudness. The timbre (sometimes called color) of the sound is also affected by the resonance of the body.
I will be interested to see if you discover any information on this topic that resembles a scientific or engineering viewpoint. I've talked to many luthiers. They all speak of the "sweetness" of the sound, the "presence," the "clarity," whether the instrument will be better for lead or accompaniment. But they never put that in words that make sense. Clearly the size of the resonating chamber affects the loudness and its depth affects the tonality: resonance with bass or treble notes. The squiggly F-holes beside the bridge of instruments of the viol family do seem to produce a noticeably different tone from the round center hole of the lute--guitars and mandolins are built both ways and you can hear the difference. An arched sounding board versus a flat one--again an audible difference. But these differences are hard to describe. Time to examine the sound wave with an oscilloscope and look for patterns. I've got it easy with a solid-body electric bass. The tone is all in the electronics.
the "sweetness" of the tone is what is scientifically referred to as the 'sound quality'. It relates to the number of harmonic standing waves which occur [in this case] on the end of the vibrating string. the more overlapping standing waves there are, the greater the sound quality. each standing wave creates a kind of semi-pitch--they overlap and extend down the length of the string to create a number of harmonics. these harmonics combine subtley to create a tone. there is a way to hear this more easily if you play around with a guitar, especially an electric one. if you pluck two strings which are perfectly in tune with each other, it will sound like one string, but it will sound better than just one string. if you turn the tuning knob of one string just slightly, so it is barely out of tune with the other, then pluck both strings, you will hear an oscillating 'wah-wah' sound which is the two different tones affecting each other to create a new wave.