The Anatomy of a Violin

What follows are the elements of design and construction basic to violinmaking. We will begin, as the violinmaker does, with the wood, and finish with the varnish.

The Wood

Split wedges of European spruce and maple are a violinmaker's traditional materials. Along with these, poplar, pear, willow, beech, ebony, boxwood, and rosewood are used variously for the purfling, linings, and fittings. Poplar, willow and other hardwoods occasionally stand in for the maple most often used for the body of the instrument.

Spruce is the wood chosen almost universally for the soundboard. It is also used for the bassbar and soundpost, and often for the blocks and linings as well. The suitability of this wood lies in its strength, lightness and resonance. Its predominant visible characteristic is its grain, and this varies in width and heaviness from tree to tree. It also varies within a tree, typically getting broader towards the center of the trunk. The quality of spruce used is of vital importance to the sound of the finished instrument.

Maple is stronger and much less prone to splitting than spruce, and is also one of the most stable of the hardwoods. It is curly maple that is sought after by violinmakers. The curl (also referred to as ‘figure’ or ‘flame’) is a pattern produced by a waviness in the grain, which shows up as the familiar striped figuration seen on the backs and sides of violins. Strong figuration occurs relatively infrequently among maple trees, and is the result of both environmental and genetic influences. Maple from the Carpathian mountains in Yugoslavia and Hungary was, and still is, particularly sought after for its broad rolling flame and its reflective sheen under the varnish.

While many varieties of spruce and maple are found around the world, the violin evolved around those found in southern central Europe. Although many of the forests which supplied sixteenth century Cremona are now much depleted, superb wood still comes from these areas. Contemporary makers are also exploring the beautiful woods native to North America and other continents.

Traditional wisdom in the harvesting of wood takes into consideration the area in which a tree has grown, its species, age and size, and the time of year in which it was cut. All of these factors influence the wood's strength, appearance and acoustical properties. By the 16th century, Italian wood-cutters had accumulated considerable wisdom in the selection, harvesting, and treatment of wood. Large amounts were cut for use in the shipyards of Venice. It is likely that violinmakers benefited greatly from this industry, just as French bow makers in the 1800's benefited from the huge quantities of Pernambuco imported from Brazil to be ground up for its valuable dyestuff.

All of the woods employed by the violinmaker must be carefully seasoned before being used. This involves storing them for a long periods of time under suitable conditions, resulting in a more stable material than new or ‘green’ wood. Violinmakers especially prize wood that has been seasoned for many years, or even decades.

The Model

‘Model’ refers to the overall shape and design of an instrument. The distinctly individual ones developed by Stainer, the Amatis, Stradivari, Guarneri del Gesu and other great makers, have achieved an almost archetypal stature. Their influence has been so compelling that few instruments have been made since that do not refer to one or another of them.

In addition to affecting the appearance of an instrument, the choice of model will influence its acoustics. We expect a certain type of sound from a Stradivari model, another from a Guarneri. Of course the individual treatment of these models, along with the choice of wood used, will have equal importance in determining the actual results.

A violinmaker may use several models – both traditional ones and those he has designed. The classical Italian methods and temperament allowed considerable variation from violin to violin, even when a single model was being used.

When considering an instrument, the player will want to check the body length, measured with a small tape-measure over the arching. This length has become standardized at about 356 mm. for the full sized violin, but varies considerably with other instruments.

The shape of the shoulders of the instrument will influence playability in the higher positions, especially with the larger members of the string family. This should be checked for comfort.

Damage to the treble corners and C-bout of the top may be the result of careless playing, or it may be that the width, the arching, the length of the C-bout, or the set-up do not allow for the bow clearance needed to comfortably avoid this damage. This should be checked with a bow in playing position.

Weight

When picking up an instrument, one of the first things one notices is the weight. This gives an indication of the overall amount of wood left in it. Violinmakers, following basic principles of good mechanical design, strive to reduce weight to the minimum consistent with a sturdy structure. There are no standard weights for stringed instruments: they will vary with the model, the properties of the wood used, and the judgment of the maker. However, an overly heavy instrument can feel both clumsy to play and tiring to hold. Excess wood in the plates (i.e. the top and back) produces a muted sound and a sluggish response. An unusually light instrument may have been thinned down too much. If so, it will tend to have a hollow tone that lacks projection and dynamic range. The body of the instrument will be susceptible to distortion.

Ribs and Lining

The sides, or ‘ribs’, are made from thin strips of maple bent to shape using moisture and a hot iron. The ribs are assembled about a form, which is the basic template on which the body of the instrument is built. The ribs are glued to the blocks, six pieces of wood (typically spruce or willow) which have been temporarily glued to the form and carved into the desired shapes. The blocks provide structural support for the corners, and for the endpin and neck. Once glued in place, the ribs are reinforced with the linings – strips of wood about twice the thickness of the ribs. These linings are usually of the same wood as the blocks – most often willow or spruce. They strengthen the rather fragile ribs and provide a wider gluing surface for the top and back.

The Arching

Why are the tops and backs of violins arched? After all, the flat surfaces found on mandolins and on many guitars are far simpler to construct.

If a violin had a flat top, the downward pressure from the bridge would stress the wood in ways it would have difficulty sustaining. This stress could be offset by the use of supporting braces, such as those found in a guitar. But an arch makes much more efficient use of the inherent strength of the wood, therefore a considerably stronger structure for its weight can be made by arching the plate. The use of arching makes possible instruments built lightly enough to vibrate freely, yet retaining the strength to withstand some fifty or sixty pounds of string tension for hundreds of years.

The use of arches by architects evolved from the simple semicircle used by the Romans to the oval and pointed shapes of later centuries. Similarly, violinmakers developed many distinct archings, exploring the visual and tonal properties of each. There are wonderful aesthetic possibilities inherent in arches, and these appeal to the sculptor in the violinmaker. Yet because the curves are so important to the sound and longevity of the instrument, the particular curves chosen must satisfy acoustical and structural, as well as visual requirements. The evolution of the violin shows a movement from the high arching and deeply channeled edges of the Amatis, Stainer, and early Stradivari, to the lower, flatter curves used by Guarneri del Gesu and by Stradivari in his mature work. This lower arching is generally found on the instruments of the 1700's which most successfully meet the demands of today's musicians.

Characteristic of classical Italian arching is a relative flatness in the longitudinal arch of the top. This flat area (best seen from the side) typically extends from the middle of the upper bout, under the bridge, and down to the middle of the lower bout. The back is usually more evenly curved, reflecting its different structural and acoustical function.

All else being equal, low arching lends depth and freedom to the sound, and the instrument may be less affected by changes in humidity. Taken to the extreme, the sound might lack quality, and the top will be subject to sinking.

High arching is associated with a sweetness of sound which may want projection and power. The upper block area of a highly arched instrument is often prone, over time, to bulging. Watch for problems with clearance between the fingerboard and belly.

The Channeling and Edgework

The arching of an instrument is accentuated by a slight channel cut around the perimeter of the instrument, just inside the line of the purfling. The depth and character of this channeling are important factors in the acoustics of the instrument.

A deeper channeling is associated with highly arched instruments. This can be seen in the work of Jacob Stainer, as well as in many of the instruments made by members of the Amati family. Guarneri del Gesu typically worked with lower arches and shallower channeling. In some cases the channel is almost non-existent and the arching rises directly from the purfling.

The Purfling

This inlay is one of the last remnants of the often extensive ornamentation gracing the earlier members of the string family. It usually consists of three strips of wood, the outer two stained black, set into a trough cut around the border of the top and back. Visually enhancing the outline of the instrument, the purfling also binds and reinforces the wood at the edges. This helps considerably in preventing cracks, especially in the top. Both the neck and the lower saddle interrupt the purfling of the top, and in a great many instruments cracks have developed in these areas. The presence of the purfling facilitates repairs to the edge, as new wood can be butted up almost invisibly against it.

Connoisseurs pay careful attention to the purfling. The materials, workmanship, and character of this inlay vary considerably from maker to maker. A clue to the origin of the instrument may be found in the type of wood used. The Cremonese tended toward poplar for the white center strips, while the Neapolitans used beech, and the Germans, maple. One finds Flemish instruments in which whale bone has been used instead of wood. Black fiber material in place of dyed wood is seen in some makers of the Gagliano family, and on many modern instruments. On instruments of a lower quality the purfling may even have been scribed in with ink, rather than inlaid.

The F-Holes

‘F-holes’ are also referred to as ‘sound holes,’ the first referring to shape, the other to their acoustical function. The violinmaker has considerable scope for personal expression when working out their shape, position, and character. Especially important are the overall length, slant, and the distance between the upper eyes. A glance at the edges of the f-holes will give a clue to the quality of the inside work: a noticeable unevenness of thickness suggests careless graduation of the top.

The overall area of the opening of the f-holes will influence the internal acoustics of the instrument. From a practical point of view, the opening must be wide enough to allow the insertion of a soundpost of sufficient diameter. Watch for damage to the right hole, caused by clumsy soundpost work.

When the arching has been finished, the violinmaker hollows out the top and back, carefully adjusting their thicknesses. This process, known as ‘graduation,’ is one of the chief means by which the maker influences the instrument's sound. Some system of measurements is usually followed, these being varied to accommodate the individual characteristics of the wood and arching, and the type of sound desired.

The maker arrives at the finished thicknesses partly through an intuitive sense of the density and flexibility of the particular wood used, and partly by measurable parameters, such as weight or tap tones. ‘Tap tones’ are the notes heard when the plates are struck in certain places. They represent the fundamental resonances of the plates, (see page * ) and their pitches depend on complex relationships between mass, flexibility, and shape. Tuning the tap tones to particular pitches can be an aid to achieving a consistent sound from one instrument to the next.

The Scroll

Except when used to hang up the instrument, the function of the scroll is entirely decorative. This allows the violinmaker wide latitude for originality. Yet apart from the occasional carved head, the scroll design settled upon by the classical makers has been used almost universally ever since. Of course its treatment in terms of depth of cut, freedom of line, cleanliness of workmanship, and overall proportion changes considerably from maker to maker.

The design of the pegbox is more closely governed by its function. It must be of sufficient strength to withstand the combined tension of the strings and the wedge-like pressure of the pegs. The layout of the pegs should insure that each string touches only its own peg.

The Neck

The neck is one of the principal surfaces with which the player comes in contact. Its dimensions and shape are of critical importance. These have been largely standardized, but there is room for variation to accommodate the size of individual players' hands. If, over the years, the neck and fingerboard have been planed down to smooth over wear, the player may become accustomed to an undersized neck. A standard neck may then feel uncomfortable, at least until it has been played for a while. When shopping for instruments, remember that an oversized neck can be shaved down, where an undersized one needs replacing – a far more costly operation..

The Workmanship

The term ‘good workmanship’ implies a soundness of construction based on thorough working knowledge of a craft. Good workmanship also involves an element of style, and in dealing with style one quickly comes upon intangibles. While two instruments can be equally functional, one may be more satisfying to look at for reasons that are not easy to explain. Good workmanship in violinmaking is often associated with precision. While this is true to a certain extent, (indeed there is an exquisite precision in the work of Stainer, or Nicolo Amati) precision quickly becomes sterile when all traces of the craftsman's hand are eliminated. A certain freedom of line and freshness of cut is in keeping with the Italian tradition. This is enjoyable for the same reason that a hand-drawn line holds the eye in a way that one drawn with a ruler does not: It is perhaps the slight irregularities which allow us feel the presence of a human being behind the work.

How precisely-made, then, should a violin be? When dealing with the set-up, and certain aspects of the structure, great exactness is required. Otherwise it is a matter of taste. Perhaps an analogy with painting is useful: Some artists work with carefully controlled and meticulous brushstrokes, others with a much looser hand. Both can be equally expressive; the difference is precisely one of style.

In appraising the workmanship of an instrument, one tends to look to the scroll, f-holes, and purfling, along with the treatment of the edges and corners. These are all areas where evidence of a violinmaker's taste and temperament show up.

The Varnish

The mystique of violin varnish centers around both the luminous beauty it can lend the surface of the wood, and the supposed effect it has on the sound. The acoustical benefits of old Italian varnish have probably been exaggerated: There are a great many antique instruments with almost no original varnish left, but whose sound remains unimpaired.

One of the principal functions of the varnish is to protect the wood. It does this both by binding the surface – helping to prevent hairline cracks from developing – and by absorbing the effects of abrasion and superficial damage. Another important function of the varnish is in slowing down the transference of moisture between the wood and the surrounding air.

An overly soft varnish may mute the sound, especially if it is laid on too thickly, and it can be prone to stickiness. When a varnish is too hard, the sound may become harsh. Brittle varnish will tend to chip off.

An ideal varnish would have a certain softness and lasting flexibility, adhere well to the wood, and be laid on with appropriate thickness. These characteristics would all contribute to good sound and the rather intangible quality of “aging gracefully”.

Varnishes are often divided into two classes; oil and spirit. The first contain some percentage of a drying oil, such as linseed or walnut, and dry by chemical changes upon exposure to light and air. Spirit varnishes, on the other hand, are solutions of resins such as mastic, seedlac or sandarac, in a solvent such as alcohol. They dry by the evaporation of this solvent. Each type of varnish has its advantages and disadvantages.

Current research suggests that the great classical varnishes contained oil soluble resins or balsams, often combined with some smaller quantity of a drying oil. All these materials had been used for centuries by painters, and their properties were well understood. Alcohol based spirit varnishes did not come into widespread usage until the late 1700's, and their adoption marks the decline of the classical period of violin making.

Traditionally, a golden or amber colored ground is the starting point in the varnishing process. As woods, oils, and many resins undergo a pronounced yellowing over time, it is uncertain how much of the yellow component seen on old violins is due to age, rather than to the original intention of the violinmaker.

One or more coats of colored varnish are usually applied on top of the ground. The final color is a matter of taste. Current taste leans towards the more muted colors of antique instruments, though this could not have always been so. Stradivari was a pioneer in the adoption of brighter shades of red. As he often worked for nobility, this choice of colors perhaps reflects the type of interior decoration favored by his clients. There may have been an element of status involved: Vivid hues required dyestuffs that were expensive at the time. Their extravagant use was a sign of wealth. At any rate, transparent and vividly colored pigments were widely available to painters of the seventeenth century, and they were certainly used by the classical violinmakers.

The bevel of the scroll and the corners of the ribs are sometimes covered with black ink. This accenting of the lines first appeared on the instruments of Stradivari and Guarneri del Gesu, though most of evidence of it has by now worn off their instruments.

Antiquing the finish of a new instrument is a practice which goes back hundreds of years. When handled well and without dishonest intent the effect can be delightful, although many musicians prefer a new instrument to look new, just as the classical Italian instruments once did.