The f-holes also play an important role in separating the area where the bridge stands from the rest of the belly, allowing this area to move much more easily in response to vibrations from the bridge. Illustration of a few of the lowest-frequency Chladni nodes of a single violin plate. A graphic showing the relationship between the input waveform of the violin -- what the player creates with the bow -- and the output waveform -- what we actually hear.
Note that both the violin bridge and the body tend to emphasize vibrations at some frequencies while damping others. The output waveform has the same overall shape as the input waveform, but the details are very different.
Graphic courtesy of Colin Gough and Physics World. The sound post and bass bar together break the symmetry of the violin body, thereby allowing the body to oscillate in different ways than if it were symmetrical, and generally increasing the sound output of the instrument.
These bands are called nodes, and the sand moves to them because they are stationary points on the plate. The other parts of the plate are moving either up or down at a given time. These patterns are called Chladni nodes after Ernst Chladni, the German physicist who developed the technique of finding such patterns on vibrating plates.
Many such modes exist, but makers concentrate on those at the lowest frequencies, tuning the plates either by tapping them to hear if they ring, or flexing them by hand. The acoustics of the assembled violin body are fantastically complex, as they involve coupled oscillations of the strings, the bridge, the top and bottom plates, the ribs, and the fingerboard. The violin body resonances do not necessarily fall at the same frequency as the notes the player wishes to play, although the first lowest-frequency body resonance of instruments generally considered of high quality falls near the fundamental frequency of the open A string, cycles per second.
In general, the frequency spectrum of the sound coming out of the violin body is very different from the spectrum going in. For instance, the violin body has almost no response at the fundamental frequency of the open G string, which at cycles per second is the lowest note on the violin in standard tuning. Each item plays a key role in how your violin makes its unique sound. Strings — your strings form the foundational vibrating object on your violin , and as such, are an integral part of sound production.
The length, mass, and tension of each violin string effects its ability to deliver a certain pitch. Bow —bowing and plucking initiates the vibration. Bridge —the bridge of your instrument plays the most important role in the sound your instrument produces.
The bridge is perfectly positioned to transfer the vibrating energy of the strings to the body of your violin, and the air it contains. Mutes are used to effect its ability, by creating more mass that hinders energy transference. Placement is key. Soundpost and Bass Bar —These items are located directly beneath the feet of your bridge, and instrumental in sound production.
The soundpost is a vertical, moveable object that connects the top and bottom plate on the treble side of the bridge E-string. It prevents the tension of the strings from collapsing the belly top plate , creates a pivot point, and channels the energy of the bridge to the belly and back plate of your violin.
We illustrate this with sound files here. To get an idea of why vibrato is so important to the violin, ask a violinist to play a long soft note on an open string, or two notes simultaneously on two adjacent open strings. On the open string, it will have no vibrato.
Now close your eyes? Can you imagine that it is an organ playing? Each time the bow changes direction you can tell that it is a violin, but during sustained, steady bowing it is much less clear. Now ask the violinist to play the same single note, or a double-stopped fifth, on different strings, and to play normally. How important is the difference? We demonstrate this with soundfiles, waveforms and spectra on the page Articulation and vibrato on the violin.
See the paper on timbre vibrato by J. The bow can be used in a variety of different ways to produce different articulations and sound effects. Some of these are demonstrated with sound files, wave forms and spectra on Articulation and vibrato on the violin. Site map Contact Us. First, something about sound.
If you put your finger gently on a loudspeaker you will feel it vibrate - if it is playing a low note loudly you can see it moving.
More about loudspeakers. When it moves forwards, it compresses the air next to it, which raises its pressure. Some of this air flows outwards, compressing the next layer of air. The disturbance in the air spreads out as a travelling sound wave. Ultimately this sound wave causes a very tiny vibration in your eardrum. At any point in the air near the source of sound, the molecules are moving backwards and forwards, and the air pressure varies up and down by very small amounts.
The number of vibrations per second is called the frequency which is measured in cycles per second or Hertz Hz. The pitch of a note is almost entirely determined by the frequency: high frequency for high pitch and low for low. A double bass can play down to 41 Hz or below, and the violin can play notes with fundamental frequencies well above 2 kHz. Human ears are most sensitive to sounds between 1 and 4 kHz - about two to four octaves above middle C.
Here is a more technical introduction to sound and hearing. The violin: strings and bow, bridge and body Strings The pitch of a vibrating string depends on four things.
The frequency can also be changed by changing the tension in the string using the tuning pegs: tighter gives higher pitch. The frequency also depends on the length of the string that is free to vibrate. The player changes this by holding the string firmly against the fingerboard with the fingers of the left hand. Shortening the string stopping it further up the fingerboard gives higher pitch.
Finally there is the mode of vibration. When you play harmonics, you induce the string to produce waves which are a whole fraction of the length of those normally produced by a string of that length. The bridge The bridge transfers some of the energy of vibration of the string to the body of the violin. Anyway, a given note on a violin will have several frequencies vibrating at once.
This distinct combination creates the uniquely beautiful timbre of the violin. However, we know that this is impossible, given the inconsistent quality of natural materials. More interesting are debates on how the body of the violin affects the resonance capabilities. If it is too thin, the sound will be "boomy. Or you could try going to your neighborhood violin shop to take a look around.
Cremer, Lothar. The Physics of the Violin. John S. Allen, trans. Cambridge: MIT, Howard, David M. Acoustics and Psychoacoustics.
Oxford: Focal,
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