The History of String Making
by William R. Cumpiano
reprinted from Frets Magazine, August 1979
UPON RELEASING an arrow from his bow, the primeval hunter must have noticed the characteristic "twang" of his bow. In a moment of leisure he may have repeated that sound for its pleasurable effect on his senses.
Later, he undoubtedly stumbled upon two major discoveries. First, he found that the twang could be made louder by coupling the bow to a hollow object, such as his mouth, an animal shell, or a gourd; or by coupling the bow to a stretched membrane, such as an animal skin. Second, he discovered that upon flexing his bow, the pitch of the twang changed. Thus, the world's first string instrument was born.
Though woven vines were used on early bows, stretched sinews and the guts of different animals were the first real instrument strings. The materials' unique characteristics made them suitable for this purpose. They were strong, allowing them to be stretched in order to function properly. They were elastic, possessing the property of returning to their original forms after being pulled or stretched out of shape.
Much later, as the dawning of civilization brought about the first polyphonic instruments, the guts from a wide variety of animals, as well as other materials, found use on such instruments as lyres and harps. References from minstrels, monks, and scholars of medieval times describe strings made from sheep gut, wolf gut, lion gut, ram gut, brass, silver, horsehair, leather, and silk.
The earliest musicians and makers had to make their own strings, of course. It wasn't until the fifteenth century that the job of string-making was transferred from the musician to the professional string maker. String-making as a craft is believed to have appeared first in Munich, Germany, in 1431. For centuries, Munich strings were the finest—and most expensive—in the world.
The development of string making, from the earliest times through the Middle Ages and the Renaissance to the present day, has followed a quest for ever more elastic and ever more uniform strings. From those two characteristics come all the qualities of playability and reliability that we take so much for granted today. Historically, these qualities were very rare. A visit to a large museum's collection of early instruments will reveal the most fascinating variety of instrument-making oddities—lutes with seven-foot-long necks, orphareons and bandoras with slanting frets, theorboes with two different string lengths on the same instrument, and instruments with literally dozens of strings—all these being technical contortions of builders trying to compensate for the various inadequacies common to early strings As we shall see, musicians themselves had to undergo contortions of their own for the sake of their art, because of the limitations of primitive strings.
Throughout the evolution of stringed instruments, the relative state of string-making technology actually determined the form of the instruments themselves. In order to understand the significance of this point, an explanation of several of the factors governing string performance will be helpful:
Two important demarcations of the useful range of a string are the "breaking pitch," or the highest possible note for a given open string length; and the "minimum stress" point or minimum slackness, meaning the lowest tension you can bring the string down to while still getting an acceptable note. Each string material had its own limits. The material chosen by the early builder for the first string of an instrument determined the highest note playable on the instrument (if a material of high tensile strength was chosen, it could be cranked up to a correspondingly high note; and of course, this still holds true). On the adjacent string, the builder could either use the same string material and tune it down (causing it to feel looser than the first string); or choose a thicker string of the same material, the increased mass allowing the string to vibrate at a lower frequency.
The range of the instrument could be further expanded downward by attaching a third string. If a duplicate of the first string was used, it probably had to be tuned below its minimum slackness, making it too slack to be useful. Thus, an even thicker string had to be used in order to have one playable at the lower pitch while still at a tension similar to that of the others.
In order to expand the instrument's bass range even further, drastic action had to be taken by the builder. If he was using gut for strings, chances were that he had found thick gut behaves terribly; it intonates poorly and produces a muffled, disappointing tone. The only recourse was to lengthen the neck of the instrument in order to use more satisfactory, thinner gut strings. Further range expansion meant longer and longer necks, and bass instruments were of enormous size—seven-foot necks were not uncommon.
This problem persisted until the technique evolved of tightly twisting the gut, increasing its elasticity in the process and allowing a comfortably tight, yet lower-pitched string on a shorter fingerboard. It was found that—within physical limits--the greater the amount of twist, the more elastic the string.
The next discovery in the quest for greater string elasticity came from the "cordiers," the nautical-rope makers, of the sixteenth century. Their technology had developed the technique of twisting several separate strands of cord, retaining uniformity and an accurate tightness of twist. When the rope makers' technique was applied to gut or wire, an increase of elasticity over the original single-strand material was found to occur. These strings were called catlines, a term borrowed from ship-rigging terminology. In French "corde" means both rope and musical string. The term "catgut," when applied to violin strings, is derived from a mistaken belief that cat guts were used as strings, because gut catlines were traditionally used on bowed instruments.
One of the last major technological advances in string making was the invention of over-spun, or "wound," strings. The discovery that gut, wire, or silk could act as a core material, around which extremely fine wire could be spun, allowed for the final increase of elasticity that instrument makers needed to solve their range problems. What is probably the earliest documented reference to over-spun strings appears in a manuscript written in 1664. It noted that,
...The recently invented way of loading gut strings makes their sound much louder; for the drawn metal wire, with which they are wound, gives vehemence to all the vibrations and the wire, being seven or eight times longer than the string, it is so loose that neither its parts or particles undergo movement in its vibrations which is able to cause any noise, so that only the string can produce noise and it can only produce that which is natural to its tension, the .windings of metal wire not being able to give it any stiffness or hardness.
As this selection implies, overspinning the string's core adds only mass to the string without adding stiffness, so a thick overspun string is no stiffer (or less elastic), than it's thin core. That's why the overspun string, when compared to a monofilament of the same gauge, results in added "vehemence" and only the "noise" which is "natural to its tension."
Increasing the elasticity of the string material not only allowed for more compact and playable instruments with an extended musical range, but also relieved many string problems that bedeviled the musician, such as pitch distortion and inharmonicity.
Pitch Distortion
Pressing a string down onto a fret stretches it slightly. This stretching sharpens the pitch. So does pressing the string down hard behind the fret. Playing loudly on a string will also sharpen the note momentarily. This rise in pitch is unnoticeable on thin strings, but it becomes a major problem on thick ones —such as the early thick gut basses. The early luthiers fought pitch distortion by setting the lowest possible action and using the lowest possible frets. Another technique, used to this day by some luthiers, was grading the frets; that is, using progressively thinner fret material up the fretboard. It is believed that the movable, tied-on frets that were used on gut-string instruments were set slightly "flat" by the musician; by controlling finger pressure on the string, various compensations and effects were achieved.
Inharmonicity
When you pluck a string you are hearing not one sound but many sounds: the fundamental (or the single, loudest, most predominant pitch) and its numerous accompanying harmonics (distinct additional pitches, each at a decreasing energy level, and at frequencies relating to the fundamental by being simple, whole-number multiples of it) A perfect string, one with sufficient elasticity and no irregularity, has a clear fundamental with harmonics lining up neatly and
mathematically behind it. A string that is lumpy or too slack has its harmonics thrown out of line, ruining the clarity of the fundamental while causing "beats" within the string and other odd behavior.
Although pitch distortion and inharmonicity were characteristic of early strings, modern strings can display the same problems. This is especially true with overused strings that are dimpled by frets, beaten by fingerpicks, and encrusted with dirt and rust. They thus lose both their elasticity and uniformity and behave much like the early strings did.
Gut strings, being of organic origin, are inherently less uniform than strings made of other materials. Gut-strung instruments historically had tied-on, movable gut frets, rather than the hammered-in frets found on instruments using more uniform wire strings. The musician would make slight adjustments to these gut frets so as to compensate for the out-of-tuneness of the available lumpy strings.
Gut strings also tend to taper from end to end. A 1517 manuscript reveals the "secret" of the master lutenist Vicenzo Capirola, who put the thick ends of the trebles at the nut and thick ends of the basses at the bridge. This system helped to counteract the sharpening of the thick bass strings during fretting, due to the increased average weight-per-unit length on the remaining portion of the vibratingstring. Even today it is advisable to reverse the ends of a "false" string and to try it again before discarding it. (A well-used, unwound string can be renewed and a false unwound string "re-trued" by twisting, which restores elasticity and uniformity. The precise technique for doing this will be described in a future article.)
Gut absorbs moisture from the air and from the fingers. It then swells, increases its tension, and goes sharp. You can easily sympathize with the seventeenth-century lutenist who first had to tune his two dozen strings, then tune his frets, and then retune shortly afterward due to sweaty fingers. These problems were less prevalent with the fantastically expensive Munich strings (called minikins), which were chosen for their high tensile strength and near-perfect uniformity. Several sets of minikins cost as much as a lute or a cello; they were affordable by only the most affluent and well-connected musicians.
It is no accident that the lute was obsolescent in the eighteenth century, making way for the simpler, easier-to-tune guitar. The "unrefined" guitar had always been the instrument of the common people. It was not until the late 1940s, when Albert Augustine developed a high tensile strength version of nylon cord, that lutes returned to the concert hall. The new material's strength, uniformity, and moisture stability all but outmoded gut on most stringed instruments.
In spite of all their problems, and the availability of a more practical alternative, gut strings are still produced today and are used by many guitarists who feel that their warm, positive trebles are superior to nylon's dryer tone.
Wire strings
The earliest reports of the technique of "drawing" wire—that is, forcing a piece of metal through succeedingly smaller holes, increasing its length and tensile strength in the process—tell of its origin in Paris in the twelfth century. Wire strings were used extensively on certain plucked instruments, such as the cittern, the Irish harp, and the harpsichord. The evolution of wire as a string material paralleled that of gut closely, and it was discovered that such metals as iron, copper, brass, silver, gold, and steel not only had their own particular range and elasticity limits but also had their own harmonic components, giving each a characteristic tonal "shine." Instruments designed for wire strings were always of more robust construction than their gut-string counterparts, due to the extra tension load.
Although it is common for modern musicians to complain about strings, or to attach fierce loyalty to one type or another, few realize what their forebearers had to put up with. Few appreciate also the degree of perfection and uniformity commonplace today that facilitates the simple, magic dance of the stretched cord--a movement as sure and predictable as the ripples in a pond or the movement of the planets.