Guitar Strings from the 18th Century to the Advent of Nylon (Part 1)

Types, Manufacturing Techniques, and Selection Criteria

By Mimmo Peruffo

“The sonic qualities of the finest instrument are diminished if it is fitted with mediocre strings.” (Emilio Pujol, *Escuela Razonada de la Guitarra*, Buenos Aires, 1934)

INTRODUCTION

When it comes to strings and the criteria for selecting guitar string configurations throughout the eighteenth, nineteenth, and part of the twentieth centuries, the study of recently uncovered historical material has not failed to elicit a certain degree of surprise. This may stem from the fact that little has been thoroughly investigated in this field thus far. Moreover, there persists a widespread notion that everything pertaining to the guitar’s past can be reduced to a series of intermediate steps in a lengthy evolutionary process culminating in what is often regarded as the ultimate goal: the advent of the “Torres guitar” (and its variants), ¹ the use of right-hand fingernails, and the abandonment of early gut strings in favor of synthetic materials. Additionally, there is a prevailing assumption—perhaps borrowed from bowed instruments adapted for performing Baroque music—that the guitar of the nineteenth and early twentieth centuries was characterized by significantly lighter stringing compared to modern standards. Regarding gut strings specifically, it is even more firmly believed that their overall acoustic performance must have been somehow inferior to that of nylon or PVDF (polyvinylidene fluoride), commonly known as “carbon,” despite the fact that very few individuals have actually tested a single gut string on their own guitar. However, what has begun to emerge from an examination of the retrieved documentation—suitably complemented by practical experimentation—strongly points to substantially different realities.
This contribution thus appears necessary, not only because a growing number of individuals are rediscovering the pleasure of performing certain repertoires on period instruments or their replicas, but also, more simply, because it represents an inherently dutiful act of recovering the (not solely musical) history of our instrument. Furthermore, it enables a more informed appreciation of guitar recordings predating the 1950s, an era when gut and silk reigned unchallenged. Thus, if the philological reconstruction of ancient musical repertoires and the restoration of the instruments associated with them cannot be divorced from a meticulous and comparative investigation of the available elements, then the string—being the very source of sound—undoubtedly constitutes the foundational element of this inquiry. Indeed, as numerous studies have already demonstrated, it is no longer merely a “stone discarded by the builder” (a simple accessory) but rather the “cornerstone of the temple.” An instrument without strings—be it a Stradivari or a Torres—lacks its own musical life, save for that produced by mere percussion.
In this discussion, metal strings have been deliberately excluded, as they began to gain prominence in the guitar world only from the second half of the nineteenth century, following the emergence of “piano steel” (circa 1840). This material, with its exceptional tensile strength compared to the iron previously used (alongside brass and bronze) in keyboard and plucked instruments such as the mandolin, was not employed in the six-string guitar. In the realm of the guitar—particularly in its “cultivated” form—exceptions to the use of gut were rare, largely confined to the folkloric “Chitarra Battente” or specific choices like that of Agustín Barrios. ²

THE FOUR AGES OF GUT STRINGS

Gut is a material with a millennia-long history of use: for instance, gut strings have been discovered in ancient Egyptian plucked instruments dating back to the Third Dynasty. ³ Over the centuries, a process of refining the techniques necessary to produce a quality string unfolded, but it was only toward the second half of the seventeenth century that this long evolutionary trajectory culminated in the revolutionary discovery and widespread adoption of wound bass strings. These consisted of a gut core entirely coated with a thin metal wire—typically silver, though copper and brass were also used. Research has led to the hypothesis that the technology of gut string manufacturing did not develop through a gradual progression but rather through abrupt shifts prompted by technological innovations, which then rapidly influenced contemporary musical instruments. This resulted in the emergence or disappearance of certain instrument classes that had remained relatively stable during “transitional” periods. This assertion can be effectively substantiated by examining, for example, the impact of wound bass strings on certain musical instruments, which directly led to the swift abandonment of the cumbersome violin basses in use until the late seventeenth century—or shortly thereafter—in favor of the emerging cello. ⁴ Their introduction also enabled the addition of a sixth string to a guitar with a relatively limited vibrating length compared to those of the recent past, without compromising acoustic performance.
It is imperative to dispel the recurring notion that ancient strings were somehow “primitive,” far removed from the presumed perfection of modern ones. Research suggests instead that the manufacturing technology of gut strings can be divided into four distinct “ages.” The “first age” of musical strings is lost in the mists of time and has been identified as a lengthy process of empirical selection of natural raw materials possessing a certain degree of tensile strength and an inherent predisposition to produce sound when twisted together—chief among them silk and gut. The latter, perhaps due to its greater availability, gained prominence in the Christian West and Mediterranean civilizations.
This was followed by the identification and progressive refinement of the most suitable manufacturing system, essentially as outlined in the numerous “do-it-yourself” recipe books of the Middle Ages—a process remarkably similar to that used today. For example, here is an anonymous recipe from the Secretum Philosophorum, fifteenth century:
“To make lyre strings: When we wish to make lyre strings […] take sheep intestines, wash them thoroughly, and place them in water or lye for half a day or more until the flesh separates easily from the string material, which resembles a sinew. Then remove the flesh from the material with a feather or a clean finger. Next, place the material in strong lye or red wine for two days. Afterward, remove it, dry it with a linen cloth, and join three or four strands together depending on the desired thickness, twisting them sufficiently. Stretch them over a wall and allow them to dry […].” ⁵
The finished product, given that manufacturing had not yet become professionalized, likely exhibited considerable qualitative variability.
The second evolutionary stage can reasonably be situated between the second half of the fifteenth century and the mid-sixteenth century. This period appears to coincide with the emergence of the string maker as a specialized figure who refined and rationalized existing manufacturing techniques, elevating the quality of musical strings to the highest mechanical and acoustic standards. Tellingly, this era saw the near-total disappearance from contemporary recipe books of do-it-yourself string-making instructions, which had been widespread in the Middle Ages. Throughout the sixteenth century, the most renowned centers for producing musical strings were also significant hubs for dyeing and spinning silk and cotton—examples include Barcelona, Munich, Nuremberg, and Lyon. It is thus plausible that string makers in these cities adopted the more complex spinning techniques used for silk, leading to an initial significant reduction in the stiffness of thicker strings employed in the bass registers of instruments.
These bass strings had to be more elastic and efficient than usual, enabling an initial morphological shift: the lute, for instance, could expand its range downward by a fourth, or sometimes a fifth, with the addition of a sixth double string (the so-called “course”) as early as the second half of the fifteenth century. A similar development occurred with bowed viols.
The third evolutionary stage can be placed around the second half of the sixteenth century, when musical instruments underwent another significant qualitative leap: the lute gained a seventh, lower course (followed by several more on the fingerboard), tuned from the outset a fourth, or sometimes a fifth, below the sixth. For bowed instruments, there is evidence suggesting a certain reduction in vibrating lengths—while maintaining the same pitch—compared to those previously in use. ⁶
Recent studies ⁷ propose that these sudden changes were driven by a revolutionary idea: increasing the weight of the gut used for bass strings through specific treatments with heavy metals. Indeed, in seventeenth-century musical iconography, it is not uncommon to observe that the strings of these registers—known from contemporary lute treatises to be exclusively gut—display colors ranging from deep red to brown, markedly different from the yellow typical of natural gut. These colorations appear precisely where modern wound bass strings are now used. Moreover, the holes for bass strings in the (presumed) original bridges of numerous historical lutes in museums are too narrow to accommodate plain gut strings unless they were deliberately weighted. Mathematical analysis demonstrates that only a specific weight double that of natural gut would allow strings thin enough to pass through these narrow holes to achieve appropriate working tensions. This treatment thus enabled the production of significantly thinner and more resonant strings than those previously used, while maintaining proper tension. This third evolutionary phase, characteristic of the era of Monteverdi and Stradella, likely marked the pinnacle of gut string manufacturing complexity, a level that has arguably remained unsurpassed.

The fourth and final “age” of musical strings—the one of relevance to us and persisting today—was marked by the revolutionary emergence of wound bass strings. These consisted of a core of gut—or sometimes silk—tightly wrapped with a thin metal wire in either closely spaced or spaced coils. This provided an alternative and far more efficient method of weighting gut compared to chemical treatments.
The earliest known handwritten documentary evidence dates to 1659: “[…] Goretsky hath an invention of lute strings covered with silver wire, or strings which make a most admirable music. Mr Boyle.” […Goretsky has invented lute strings coated with silver wire, that is, strings that produce music in a truly admirable manner] and further: “[…] string of guts done about with silver wire, makes a very sweet music, being of Goretsky’s invention.” ⁸
This was followed chronologically by John Playford’s Treatise for the Viola da Gamba of 1664, which can be considered the “official” announcement of this innovation to the musical world of the time. ⁹ However, the dissemination of these new, more efficient bass strings was not as rapid as one might assume: notably, the viol player Sainte-Colombe introduced them in France only around 1675. ¹⁰
In Italy, a country long renowned for producing high-quality musical strings, evidence emerges from 1677; ¹¹ nonetheless, the earliest known European pictorial representations of instruments (violin and cello) featuring wound bass strings date to around 1681–1685. Here, the fourth bass string of these instruments appears white, likely wound with silver or silver-plated copper. ¹² For plucked instruments like the lute, however, there remains to date no noteworthy iconographic or written evidence attesting to their use.

The influence of this new invention on instrument construction and musical practice was, needless to say, revolutionary—so much so that it can be regarded as a true dividing line between what came before and after. Indeed, while the vibrating lengths of higher-pitched instruments like the violin remained “human-sized,” those of larger instruments had always been disproportionately long relative to the reach of the left hand’s fingers, at least until the advent of wound strings. It is easy to infer that once early musicians gained access to far more robust bass strings, their immediate inclination was likely to systematically reduce the vibrating lengths of certain instruments (e.g., the viola bass) or even introduce new ones (e.g., the cello), thereby enhancing performance agility. This paved the way entirely for new musical forms and, by the late eighteenth century, facilitated the addition of the sixth bass string to the guitar, accompanied by a significant reduction in the instrument’s vibrating length and the abandonment of courses (and fretboard ligatures) in favor of single strings.

MANUFACTURING TECHNIQUES FOR STRINGS BETWEEN THE MID-EIGHTEENTH AND LATE NINETEENTH CENTURIES

At first glance, the manufacturing process for strings in the eighteenth and nineteenth centuries appears strikingly similar to that of today, but in reality, there are substantial differences that suggest the strings of that era—at least until the late nineteenth century—were more elastic and, quite likely, superior to ours in terms of durability and acoustic performance. The procedure of the time typically involved the use of whole lamb gut (which, when emptied and degreased, appears as a flat, semi-transparent membrane approximately 34 mm wide) with a length of at least fifty feet. ¹³
After being thoroughly emptied and rinsed in running water for several days, the gut underwent a series of treatments to remove unnecessary parts, leaving only the perfectly degreased muscular membrane—the material of interest to the string maker. This was achieved by soaking the gut in alkaline baths of gradually increasing concentration for several days; subsequently, with a simple and gentle scraping using the back of a knife or a piece of marsh reed, the non-muscular membranes and fat invariably accompanying the gut were easily removed. The alkaline baths consisted of plant ashes mixed with water (potash). The progressive increase in bath concentration might be explained by the fact that, at the start of the degreasing process, diluted alkaline solutions suffice to remove the more easily soluble fatty substances, with the highest potash concentration reserved for the end, when a more vigorous action is required to eliminate remaining stubborn material. At this stage, a modest amount of rock alum could also be added, its astringent and tanning effects slightly hardening the gut.
In other words, the alkaline baths induced a process of fermentation and saponification of the organic matter, facilitating the mechanical detachment of unwanted parts. The degreased gut was then carefully sorted and gathered into parallel bundles of varying quantities (depending on the desired string diameter, up to fifty for a double bass), knotted at the ends, and subsequently twisted using a dedicated spindle. The opposite end of the proto-string was secured to a peg fixed to one side of a drying frame. After adequately twisting the string, the free end was attached to another peg on the opposite side of the frame, thereby tensioning the damp string.
Once the frame was fully strung, it was moved to a small, designated room where the strings underwent a whitening process through sulfuring: they were exposed for days to the bleaching action of sulfur dioxide produced by burning sulfur flowers in a basin. Upon completion of this step, the strings were further twisted, then subjected to final drying in open air, a process taking just a few hours. Fresh gut, resembling a water-soaked sponge, undergoes significant diameter reduction upon drying: a freshly whitened string of about 5 mm in diameter shrinks to a yellowish one of approximately 1 mm once dried. The final stage involved smoothing their rough surface through abrasion with a plant possessing abrasive properties (soaked in the alkaline degreasing liquid, or “temper”): horsetail, rough horsetail, or scouring rush. Only in the nineteenth century did the use of powdered pumice begin to gain preference.

The perfectly smoothed strings were then coated with olive oil, cut from the frame ends, and packaged in coils; each oiled paper package could contain fifteen to thirty strings or more. ¹⁴ It might initially seem that the modernization of this centuries-old, largely unchanged string-making technology was wholly positive, but the reality is more nuanced. Certain seemingly trivial steps in the traditional manufacturing process have never been adequately investigated; the practical difference becomes apparent when comparing the few surviving string samples—even from the early twentieth century—with those available today: the former are highly twisted, soft, and elastic, while the latter are generally rigid and minimally twisted. Moreover, unless coated, modern strings typically have a significantly shorter lifespan once mounted on an instrument.
The issue of durability can be readily explained by the fact that a string made from whole gut, treated only with light abrasion using an abrasive plant or pumice, exhibits far fewer broken surface fibers compared to a string made from gut strips whose final diameter has been mechanically ground down. Such grinding can remove substantial amounts of material from the rough string’s surface, making it more prone to premature fraying. The second critical factor—greatly affecting overall acoustic performance—relates to the apparent tendency of today’s gut strings to prioritize tensile strength over maximum elasticity due to their low twist: it is often overlooked that a musical string’s primary function is to produce optimal sound, not to rival a towing rope. In other words, strings must be capable of converting the mechanical impulse from the finger into a vibrational motion that, as far as possible, is free from internal friction within the string, which would reduce the efficiency of transforming transmitted mechanical energy into sound.

That modern strings are generally less twisted than those of the past is inferred not only from information in ancient documents but also from examining surviving fragments; it hardly needs stating that the degree of twist is fundamental in determining a gut string’s elasticity: a highly twisted string is invariably less rigid and more resonant. ¹⁵ This leads to the conclusion that historical musical strings were likely superior—in terms of acoustics and durability—to ours, which, at the very least, boast precise dimensions and thus are rarely “false,” a persistent issue with strings before the advent of mechanical grinding introduced only after the mid-twentieth century.

PRODUCTION CENTERS

During the seventeenth century, Rome was undoubtedly the most prestigious center for producing musical strings in Italy and Europe. By 1735, it boasted around twenty string-making workshops (regulated by strict statutory ordinances) capable of supplying all of Europe with high-quality musical strings. ¹⁶ Roman treble strings remained renowned well into the late eighteenth century, when the powerful Roman string makers’ guild was dissolved. The mantle of quality was then carried forward throughout the nineteenth century and beyond by the skilled string makers of Naples, closely followed by those of Padua (notable in 1786 are the string maker Antonio Bagatella and the workshop “Antonio Fratelli Priuli, known as Romanin,” founded in 1613 by Antonio Romanin, possibly of Roman origin), where the production of musical strings ceased permanently in 1911. ¹⁷
De Lalande wrote: “The manufacture of violin strings is almost an Italian monopoly, as Rome and Naples supply all of Europe, and there is always much mystery surrounding these exclusive branches of commerce…” ¹⁸
Galeazzi provides the following insight: “Finally, regarding strings: one must procure strings from the best factories in Italy, which are those of Padua, Naples, Rome, Budrio in the Bolognese region, and L’Aquila in Abruzzo. There are also other factories in Città di Castello, Perugia, Rieti, Teramo, and elsewhere, but the former hold the highest repute, especially those of Padua and Naples.” ¹⁹
The violinist Spohr notes: “There are Italian strings and German strings, of which the former are to be preferred; though even among Italian strings, there are poor ones. Generally, the best are Neapolitan strings, followed by those from Rome, and then those from Padua and Milan; the latter, however, are of little value.” ²⁰

The unmatched quality of treble strings for violins—and other instruments ²¹—produced in Naples has long posed a genuine conundrum for the French, who excelled at crafting all types of strings except violin trebles. These were thus imported in large quantities from Italy, reportedly at exorbitant prices. Toward the late eighteenth century, the French even established a prize for whoever could match the quality of Neapolitan products. The gold medal was ultimately awarded to the Parisian string maker of Neapolitan origin, Savaresse, who brilliantly resolved the mystery: the “secret” lay in the use—unlike in France—of gut from relatively young animals in Naples and many other parts of Italy, a detail De Lalande had already noted decades earlier in his Voyage. ²² Italy’s preeminence in string quality persisted into the late nineteenth century, as George Hart observed:
“Musical strings are manufactured in Italy, Germany, France, and England. The Italians rank first, as in past times, their proficiency being evident in the three chief requisites for strings: high finish, great durability, and purity of sound. There are manufactories at Rome, Naples, Padua, and Verona […] The German strings now rank next to the Italian, Saxony being the seat of manufacture […] The French take the third place […] The English manufacture all qualities, but chiefly the cheaper kinds […]” ²³
Forino (1905) similarly reports:
“…famous were the factories of Berti and Colla in Rome, and Ruffini in Naples. Today, the products of Righetti in Treviso, Raffaele di Bartolomeo in Naples, Nicola Morante in Tavernale di Barra (Naples), Nicola Di Russo and Raffaele Pistola Profeta (Ruffini’s successor) in Salle (Pescara), Luigi D’Orazi also in Salle, and Conti in Mugellano (Rieti) are highly regarded […] Following Italy and Germany, France ranks third, producing excellent strings especially for harp: the strings of Lyon enjoy a reputation for excellence.” ²⁴
Emilio Pujol, the only guitarist known to us who explicitly commented on guitar string production, wrote in his method:
“The best strings today seem to us to be those of the Pirastro brand, particularly those with a golden label. Their sound is clear without being shrill; their tuning is generally accurate, and their durability and resistance remain unsurpassed. The ‘Pirazzi,’ ‘Padova,’ ‘Elite,’ and ‘El Maestro’ brands are also gut strings of excellent quality. Wound silk strings typically offer accurate tuning. Good ones are made in Valencia by José M. Dutrá, in Munich by H. Hauser, and others whose origins I cannot specify due to lack of knowledge.” ²⁵
It can readily be inferred that the manufacture of wound strings was primarily the domain not of string makers but of luthiers, if not musicians themselves. ²⁶

CRITERIA FOR EVALUATING STRINGS

But what were the guiding criteria distinguishing a good string from a poor one?
It must first be emphasized that professional musicians of the time, including guitarists, demonstrated remarkable skill in discerning quality material by touch and sight (the region of origin was itself considered a reliable indicator). This knowledge was traditionally passed down from master to pupil through a blend of oral and written tradition, ²⁷ a chain that may have begun to break at the dawn of the twentieth century. This was when the practice of blindly relying on large string-making companies—emerging in Germany and France (though not in Italy, where the artisanal string maker was nearing its end; after the Great War, most either shuttered their workshops or emigrated, primarily to America, hastening the decline of Italy’s centuries-old string-making tradition)—gradually took hold. These companies effectively imposed their manufacturing strategies and standardized commercial gauges. ²⁸

The centuries-old tradition of oral transmission might explain why guitar methods of the period contain scant information on string selection criteria, with what little is known derived primarily from violin methods—around which much revolved—or from manuals on bowed instrument lutherie in general. Below are excerpts from the sources available to us:
M. Corrette: “Those most uniform under the fingers and transparent are the best.” ²⁹
F. Galeazzi: “A good string must be translucent, golden in color—that is, tending toward a yellowish hue, not white as some prefer—smooth and polished, though this is independent of pumicing; free of knots or joins; highly elastic and strong, not limp or yielding.” ³⁰
A. Labarraque: “The best string, and the one that will last longest, is that which changes least in appearance when mounted […].” ³¹
L. Spohr: “…A good string is distinguished by its white color, clarity, and smoothness […]. Old, damaged, or poorly made strings are immediately recognizable by their yellow, dull color; they lack transparency and elasticity, unlike good strings.” ³²
Maugin et Maigne: “Treble strings, says Mr. P. Savaresse, must be transparent, perfectly uniform, and highly consistent in gauge. They must not be too white, as this would indicate they were made from lambs too young, and when a bundle of treble strings is pressed by hand, they should feel elastic and spring back promptly like a steel spring. […] Thicker strings, namely the second and third, must, conversely, be transparent and very white. They should also be very soft when a bundle is compressed, yet not change color and should quickly return to their cylindrical shape; if they appear too rigid, this would suggest they were made from overly tough gut, resulting in poor sound quality.” ³³
G. Hart: “Choose those that are most transparent; the seconds and thirds, being made with several strands, are rarely very clear […] and thus, a lack of transparency in their case denotes inferior material.” ³⁴
The final document presented here, published in 1905, likely represents the last text to outline string selection criteria according to nineteenth-century tradition:
L. Forino: “German strings boast durability and, like all products from that nation, the advantage of a good price. They are extremely smooth, hard to the touch, almost like steel [!]: even their sound reflects this hardness […]. A good string must not be overly smooth or white, as pumicing detracts from good sonority; it must be highly elastic and perfectly cylindrical […]. To test elasticity, simply compress a coiled string with your fingers and compare, for instance, a German one with an Italian one.” ³⁵

WORKING TENSION AND TACTILE PERCEPTION OF STIFFNESS

The most significant and universal criterion guiding the selection of string configurations for any plucked or bowed instrument from the Renaissance until at least the mid-nineteenth century was that all strings, when pressed at the same point, should exhibit an equal tactile perception of stiffness. ³⁶ This principle was reiterated ad nauseam over the centuries by the most authoritative treatise writers, who also noted that strings should neither be too “hard” nor too “soft.” It is clear that while the criterion of “equal tactile stiffness” across all strings is a universal standard (equal means equal), the notion of how “hard or soft” they should be (essentially, the choice of appropriate gauges) is highly subjective, tied to individual sensitivity, the type of instrument, and other factors:
T. Mace: “Another general observation, indeed the most important, is this: whatever the scale length of the lute you are stringing, you must select your strings such that (in the tuning you intend to use) all strings exhibit a proportionate and equal stiffness; otherwise, two major inconveniences arise—one for the performer and one for the listener. Note that when we say a lute is not equally strung, it means some strings are stiff while others are slack.” ³⁷
Robert Dowland: “[…] These double basses must neither be stretched too hard nor too weakly, so that when struck with your thumb and other fingers, they produce in you the same sensation as the treble strings.” ³⁸
The Burwell Lute Tutor: “[…] When you stroke all the strings with your thumb, you must feel an equal stiffness […].” ³⁹
These highly functional rules are now almost entirely overlooked (even by the few who seek to understand the rationale behind a commercial string set), supplanted by the concept of working tension expressed in kilograms or, worse still, by terms like “light,” “medium,” “thick,” etc., printed on packaging, thus eliminating any scope for conscious reasoning or experimentation by the musician. It is often assumed that equal tactile stiffness across strings (a universal rule for plucked or bowed instruments) corresponds perfectly to equal tension, but this is not the case. ⁴⁰
Let us clarify this crucial point, which has negatively impacted the reconstruction of string configurations for all plucked and bowed instruments of the Renaissance and Baroque, as well as modern configurations for the five-course Baroque guitar or the six-string Romantic guitar and beyond. While working tension is a numerically precise value defined by itself, the tactile perception of stiffness—being a sensation—is subject to various factors.
Here are some examples: between two identical strings under the same working tension but with different vibrating lengths, the longer one will feel more yielding to the touch; similarly, between two gut strings of equal gauge, tension, and vibrating length—one highly twisted and the other minimally so—the former will feel more yielding under finger pressure due to greater longitudinal elastic give (this explains why replacing a string of a given gauge from one commercial brand with another of different provenance is often problematic: differences in twist, material type, and processing can render gauge equivalence irrelevant to achieving the same tactile stiffness). Finally, between two strings with identical twist, vibrating length, and tension but differing gauges, the thinner one will feel more yielding. It is easy to see the tactile inconsistencies that arise in an instrument like a chitarrone (characterized by strings mounted at two different vibrating lengths) when strung—as is common today—with equal tension rather than adhering to historical criteria. In summary, when documents from that era—at least until the mid-nineteenth century—refer to “tension” in the context of an actual string configuration (not theoretical speculations about relationships between physical parameters like frequency, vibrating length, gauge, etc., as in Mersenne’s treatise and others), they essentially mean tactile perception of stiffness, not tension in kilograms as universally understood today. Galeazzi provides a particularly pertinent example: “…the tension [in the violin, ed.] must be the same for all four strings, for if one were more tense than another, it would produce under the fingers and bow a noticeable inequality, greatly detrimental to the evenness of tone.” ⁴¹
It is evident that “tension” here equates to tactile stiffness. Bartoli’s treatise similarly clarifies this equivalence: “The closer a string is to the origin of its tension, the more tense it is there […]. Consider now any lute string: it has two equally potent tension origins—the tuning pegs at one end and the bridge at the other—thus, as stated above, it is more tense the closer it is to them and, consequently, less tense in the middle.” ⁴²

1. For a broader discussion of the topic, see: Stefano Grondona and Luca Waldner, La Chitarra di Liuteria, L’Officina del Libro, Sondrio, 2001.
2. Barrios’s choice of metal strings might be justified—beyond purely aesthetic reasons—by the absence of autonomous gut string production in South America, necessitating their costly and time-consuming importation from Europe. A second, no less significant hypothesis relates to the hot, humid climate of Paraguay (where Barrios lived), where gut strings would have an extremely limited lifespan. The use of metal strings was vehemently opposed by Segovia, who, during a 1944 meeting with Barrios in El Salvador, bluntly described his guitar as “a wire fence.” See Richard Stover, “Agustin Barrios Mangoré. His Life and Music. Part III: Cacique Nitsuga Mangoré,” Guitar Review, no. 100, Winter 1995, pp. 20–21.
3. Werner Bachmann, The Origins of Bowing and the Development of Bowed Instruments up to the Thirteenth Century, Oxford University Press, London, 1969 (original edition: Die Anfänge des Streichinstrumentenspiels, Breitkopf und Härtel, Leipzig, 1964), p. 79.
4. Stephen Bonta, “From Violone to Violoncello: A Question of Strings?,” Journal of the American Musical Instrument Society, vol. III, 1977, pp. 64–99.
5. Christopher Page, Voices and Instruments of the Middle Ages: Instrumental Practice and Songs in France, 1100–1300, J. M. Dent & Sons Ltd., London, pp. 234–245.
6. Djilda Abbot and Ephraim Segerman, “Strings in the 16th and 17th Centuries,” The Galpin Society Journal, XXVII, 1974, pp. 48–73.
7. Mimmo Peruffo, “The Mystery of Gut Bass Strings in the Sixteenth and Seventeenth Centuries: The Role of Loaded Weighted Gut,” Recercare, V, 1993, Rome, pp. 115–151. Abbot and Segerman, op. cit., introduced in the 1970s the theory that bass register strings were twisted using techniques akin to marine rope construction to enhance elasticity and sonority, possibly giving rise to the term “Catline,” a type of bass string popular in the seventeenth century, also cited by Dowland.
8. Samuel Hartlib, Ephemerides, manuscript (location unknown), 1659; private communication provided to the author by Robert Spencer, 1995. Spencer suggests that information regarding wound strings was supplied to Hartlib by the renowned chemist Robert Boyle.
9. John Playford, An Introduction to the Skill of Music […]. The Fourth Edition Much Enlarged, William Godbid for John Playford, London, 1664; see also Claude Perrault, Œuvres de Physique […], Amsterdam, 1727 (1st edition, 1680), pp. 224–225; chapter: “Invention nouvelle pour augmenter le son des cordes.” See Fig. 1 above.
10. Jean Rousseau, Traité de la Viole […], Christophe Ballard, Paris, 1687.
11. Patrizio Barbieri, “Cembalaro, Organaro, Chitarraro e Fabbricatore di Corde Armoniche nella ‘Polyanthea Technica’ di Pinaroli (1718–32): Con Notizie Inedite sui Liutai e Cembalari Operanti a Roma,” Recercare I, 1989, p. 198 (from an invoice by guitar maker Alberto Platner: “…two violone strings, one of silver and one plain”).
12. See the painting by Antonio Domenico Gabbiani, “Portrait of Musicians at the Medici Court” (Florence, 1684–1687), Florence, Palazzo Pitti, inv. 1890, reproduced on the cover of Early Music, XVII/4, November 1990.
13. François de Lalande, Voyage en Italie […] Fait dans les Années 1765 & 1766, 2nd edition, vol. IX, Desaint, Paris, 1786, pp. 514–519.
14. It is noteworthy that in seventeenth-century musical iconography, excess string length on an instrument was often coiled into a bundle, as if it were soft twine. This strongly suggests that strings of the period were extremely pliable. From the eighteenth century onward, strings were packaged in a circular profile, seemingly confirming changes in string-making practices, possibly following the advent of wound strings.
15. Abbot and Segerman, in Strings in the 16th and 17th Centuries…, were the first to propose that gut strings were made with both low and high twist. More precisely, Segerman argues that until the late Middle Ages, strings were minimally twisted; only later, in the mid-sixteenth century, did string makers realize that greater twisting improved acoustic performance. Our perspective, however, posits that strings were consistently produced with a high degree of twist from the outset—except perhaps for the most stressed strings, such as lute trebles—and that this was no secret, given the simplicity of the process, which merely involved adjusting the number of turns on the twisting wheel.
16. Statute of the University of String Makers of Rome, State Archives, Camerale II, Arts and Trades, Statutes, coll. 312, envelope 12, year 1642.
17. Based on research conducted by us at the Padua Chamber of Commerce, it appears that the Romanin factory was managed from 1849 by the Calegari family until its transfer to the firm “Eredi Nicola Bella” of Giuseppe Drezza in Verona, who did not continue producing musical strings, thus ending Padua’s long and illustrious string-making tradition forever.
18. “La fabrication des cordes de violon est une chose qui est presque réservée à l’Italie, Naples & Rome en fournissent toute l’Europe & il y a toujours beaucoup de mystère dans ces branches exclusives de commerce…” François de Lalande, Voyage en Italie […] Fait dans les Années 1765 & 1766, 2nd edition, vol. IX, Desaint, Paris, 1786, pp. 514–519.
19. Francesco Galeazzi, Elementi Teorico-Pratici di Musica, con un Saggio sopra l’Arte di Suonare il Violino […], Pilucchi Cracas, Rome, 1791, p. 71.
20. Louis Spohr, Violinschule, Tobias Haslinger, Vienna, 1832, pp. 13–14.
21. Antoine Germain Labarraque, L’Art du Boyaudier, Imprimerie de Madame Huzard, Paris, 1822, pp. 31–32.
22. De Lalande, op. cit., p. 514.
23. “Musical strings are manufactured in Italy, Germany, France and England. The Italians rank first, as in past times, in this manufacture, their proficiency being evident in the three chief requisites for string, viz. high finish, great durability, and purity of sound. There are manufactories at Rome, Naples, Padua and Verona […]. The German strings now rank next to the Italian, Saxony being the seat of manufacture […]. The French take the third place […]. The English manufacture all qualities, but chiefly the cheaper kinds…” George Hart, The Violin and Its Music, Dulau and Schott, London, 1881, pp. 46–47.
24. Luigi Forino, Il Violoncello, il Violoncellista ed i Violoncellisti, Hoepli, Turin, 1905, pp. 55–56.
25. “Las mejores cuerdas nos parecen ser hoy las de la marca Pirastro; y de éstas las que llevan una etiqueta dorada. Su sonido es claro sin ser chillón; su afinación es generalmente justa, y su resistencia y duración no han sido hasta ahora superadas. Las marcas ‘Pirazzi,’ ‘Padova,’ ‘Elite’ y ‘El Maestro’ son también cuerdas de tripa de excelente resultado. Las de seda hilada suelen ser de afinación justa. Son buenas las que fabrica en Valencia José M. Dutrá, las de H. Hauser de Munich, y otras que por ignorar su procedencia, no puedo precisar.” Emilio Pujol, Escuela Razonada de la Guitarra, Basada en los Principios de la Técnica de Tárrega, Libro Primero, Ricordi Americana, Buenos Aires, 1934, p. 33.
26. F. Galeazzi, op. cit., pp. 74–76.
27. Dionisio Aguado, Nuevo Método para Guitarra, Madrid, 1843, in Chapter VII, point 32, wrote: “The guitarist must be a master of strings.”
28. Arthur Broadley, “String Gauges,” The Strad, April 1900, p. 371: “At the present time the matter of string thickness seems to rest entirely with the makers, the player has practically to take what is given to him.”
29. “Les plus unies sous le doigt et transparentes sont les meilleurs…” Michel Corrette, Les Dons d’Apollon…, Paris, 1763, p. 221.
30. F. Galeazzi, op. cit., pp. 71–72.
31. “La corde la meilleure et qui doit faire le plus long usage, est celle qui change le moins d’aspect quand on la monte […].” Labarraque, op. cit., p. 131.
32. Spohr, op. cit., p. 14.
33. “Les chantarelles, dit M. P. Savaresse, doivent être transparentes, parfaitement unies et assez régulières de grosseur. Elles ne doivent pas être trop blanches, car cela prouverait qu’elles ont été faites avec des agneaux trop jeunes, et lorsqu’on serre un paquet de chantarelles sous la main, elles doivent paraître élastiques et revenir promptement comme le ferait un ressort d’acier. […] Les grosses cordes, deuxième et troisième, doivent, au contraire, être transparentes et très blanches. Il faut, en outre, qu’elles soient très molles quand on en comprime un paquet, mais elles ne doivent pas changer de couleur et elles doivent revenir promptement à leur état cylindrique; si elles présentaient trop de raideur, cela indiquerait qu’elles ont été faites avec des boyaux trop résistants, et, dans ce cas, elles auraient une mauvaise qualité de son.” Jean-Carl Maugin and Walter Maigne, Nouveau Manuel Complet du Luthier, 2nd edition, Roret, Paris, p. 184.
34. “Choose those that are most transparent; the seconds and thirds, as they are made with several threads, are seldom very clear […] and hence, absence of transparency in their case denotes inferior material.” Hart, op. cit., pp. 49–50.
35. Luigi Forino, op. cit., pp. 55–56.
36. “Equal tactile perception of stiffness” refers to the same degree of lateral displacement obtained between two or more strings—potentially differing in gauge, vibrating length, twist, tuning, etc.—under the same amount of weight (typically akin to the pressure exerted by a finger or bow) applied at the same point.
37. “Another general Observation must be This which indeed is the Chiefest: viz. that what siz’d Lute soever, you are to String, you must so suit your Strings, as (in Tuning you intend to set in at) the Strings may all stand, at a Proportionable, and ever Stiffness, otherwise, there will arise Two Great Inconveniences: the one to the Performer, the other to the Auditor. And here Note, that when we say, a Lute is not equally Strung, it is, when some Strings are stiff, and some slack.” Thomas Mace, Musik’s Monument […], the author & John Carr, London, 1676, Chapter VI, pp. 65–66.
38. “[…] these double basses likewise must neither be stretched too hard, nor too weak, but that they may according to your feeling in striking with your Thumb and fingers equally counterpoise the Trebles…” John Dowland, “Other Necessary Observations Belonging to the Lute,” in Robert Dowland, Varietie of Lute-Lessons […], Thomas Adams, London, 1610, paragraph: “Of Setting the Right Sizes of Strings upon the Lute.”
39. “[…] when you stroke all the strings with your thumb must feel an equal stiffness […].” The Burwell Lute Tutor, manuscript ca. 1670, facsimile with introduction by Robert Spencer, Boethius Press, Leeds, Chapter IV: “Of the Strings of the Lute…”
40. Segerman, in Strings Through the Ages, part 1, p. 55, writes: “A more real advantage of equal-tension stringing is that the ‘feel’ of each string is the same in the sense that the same force at the same relative position on the string pushes aside (or depresses) each string the same amount…” Stephen Bonta, in “Further Thoughts on the History of Strings,” The Catgut Acoustical Society Newsletter, XXVI, 1 November 1976, p. 22, referring to Thomas Mace’s indications of uniform tactile stiffness across lute strings, writes: “…it seems clear that tensions [meaning equal kilograms] between top and bottom strings on these instruments cannot have been too disparate for the very same reasons.”
41. F. Galeazzi, op. cit., pp. 72–73.
42. Daniello Bartoli, Del Suono, de’ Tremori Armonici e dell’Udito, Treatises of Father Daniello Bartoli of the Society of Jesus, Rome, 1679, published by Nicolò Angelo Tinassi, 4°, 8 + 330 + 1 pp.; Property of Roberto Regazzi, Bologna.