Early Music Blog

Wound strings for bowed and plucked instruments from the late 17th century to the early 19th century: what do we know?


Nowadays, the first known mention of the appearance of wound strings dates back to 1659 (Samuel Hartlib Papers Project; Ephemerides: “Goretsky hath an invention of lute strings covered with silver wyer, or strings which make a most admirable musick. Mr Boyle. […] String of guts done about with silver wyer makes a very sweet musick, being of Goretskys invention”), followed then by John Playford (“An Introduction to the Skill of Music…”) in 1664. But their further distribution, in the first decades after their appearance, was not at all fast, but non homogeneous and scattered, at ”Leopard spots”.

Italy, a country that has always been renowned for the production of harmonic strings, offers us a document from 1677 where, in an invoice by the luthier Alberto Platner, one can read: due corde di violone, una di argento et un’altra semplice
(“… two violone strings, one in silver and the other one simple…”).

The first iconographic representations of stringed musical instruments using such strings date back to after 1690 (see the pictorial artworks of Anton Gabbiani, Florence, or of the French painter Francois Puget, Paris 1688, and other authors).

According to Rousseau (Traité de la Viole, 1685), it was the violist Sainte Colombe who first introduced them in France around 1675, but the main English treatise for Lute and Bass by Viola dated back to the second half of the 17th century (Thomas Mace: “Musick’s Monument”  London 1676) still does not mention them, but only describes basses in pure gut: the Lyons and the dark red Pistoys.

Claude Perrault (Ceuvres de physique […], Amsterdam 1680 pp. 214-5) has one of his paragraphs titled: “Invention nouvelle pour augmenter le son des cordes” (“New inventions to augment the sound of a string”). This is certainly regarding wound strings.

In James Talbot’s manuscript (1700 circa) the basses of Lutes, Violin and Violin Bass are still the traditional ones, in only gut: that is, the Lyons and the Catlins.

In the first decades of the eighteenth century, wound strings took over almost everywhere compared to the traditional gut only basses, on both plucked and bowed instruments, totally revolutionizing the way of making music up to the present day.

A recently discovered Roman document, dated 1719, not only states in writing for the first time the use of a fourth wound string on the Violin, as an alternative to the usual naked gut, but also states its construction data, in other words the diameter of the core and the wire to be used (see Patrizio Barbieri, 2016: “Musical instruments, gut strings, musicians and Corelli’s Sonatas at the Chinese Imperial Court: The gifts of Clement XI, 1700-1720”).

An important testimony regarding the use of a fourth wound string comes from Count Giordano Riccati (“Delle corde ovvero fibre elastiche… ” 1767) and then, along the course of the 18th century, also from various other Italian, French, Austrian, German and English documents, where the use of wound strings is described also for the following instruments: Viola da braccio, Cello, Double bass, Viola bass and finally Pardessus.

From the middle of the eighteenth century, however, the use of wound strings became a standard everywhere; around 1750-60, the Cello switched to using a wound string also on the third one.




  1. Use of exclusively round wire;
  2. Use of metals such as copper, pure silver, silver-plated copper and brass. There were still no metals such as aluminum, tungsten (or wolfram) or special alloys which began to be used only in the first half of the 20th century.
  3. High-twist natural gut core;
  4. No silk between the core and the covering wire;
  5. Different balance between core and metal winding compared to modern coated ropes (even if made on a gut core).

The strings were made using very simple winding machines:

winding machines


winding machines




The types of wound strings used between the end of the 17th century and the end of the 18th century can be traced back to three varieties:

  • wound strings on a gut core with close metal winding;
  • wound strings on a gut core with open coil winding;
  • wound strings on a gut core with a double metallic close winding.

In the second half of the 18th century, type 1 strings began to be manufactured also on a silk core, but only for plucked instruments (practical tests carried out by us have shown that coated silk strings do not work well under the bow). The strings with close winding on a gut core were those that characterized the entire nineteenth century until the early decades of the twentieth century, when, right after the Great War, those spun in aluminum and/or with partially polished metal wire began to spread.

In the 18th century, type 2 strings were called ‘a demì‘ or more generically ‘demifileè‘ strings by the French.

Their construction characteristic is clearly deducible from their name: their winding had a spacing between the loops equal to the diameter of the wire, or slightly more for plucked instruments (this precious construction indication – the only one of the eighteenth century – comes from Le Coq, Paris 1724, regarding the strings for the five-course Guitar):


For bowed instruments, it is assumed that the metal wire was more spiralized (this way, the horsehair of the bow was not channeled):


This is our translation of what Stradivari wrote: ’Questi sono i campioni delle tre corde grosse; la corda che mostra attraverso le sue spire che l’anima è fatta di budello và ricoperta con una spira molto aperta ad imitazione della pianta Vitalba

(These are the samples of the three large strings; the string that shows through its coils that the core is made of gut should be covered with a very open spiral as an imitation of the Vitalba plant)

the Vitalba plant

An example of the Vitalba plant


The first mention of this type of string, however, dates back to 1712 (Sebastien De Brossard: ‘Fragments d’une méthode de violon’, manuscript), while the last of our knowledge is dated 1782 (Jean-Benjamin De Laborde ‘Essai sur la musique ancienne et moderne’).

The demifilèe strings – always made on a gut core – were used in France sometimes both as the fourth c-string of the seven-stringed viola bass (see the letter of G. B. Forqueray to Prince Friederich Wilhelm of 1768) and as the third of the violin (Brossard 1712 and Laborde 1782):


Five-course Guitars

In addition to the already mentioned Le Coq (1724), we have further documents that confirm the use of wound strings having both gut cores (Corrrette 1761 ca) and silk cores (Don Juan Guerrero: “Methode pour Aprendre a Jouer de la Guitarre”. Paris 1760):

4-course and 6-course Mandolins

Documentation from the 18th century testifies both to the use of demì strings on a gut core and bass strings with close winding on a silk core or even gut (Methods of Fouchetti and Corrette, Paris 1771-72):

Lutes and Gallichons

The first mention of the actual use of wound strings on gut cores dates back to 1715 (Germany); several other French and, above all, German written sources from the 18th century were later discovered, confirming the fact that the 11- and 13-courses lutes used wound on gut cores. Some clues, both in terms of surviving artefacts and iconography, lead us to believe that they were of the demifilè type (we made exhaustive tests using a silk core, but they led to rather disappointing results, both in terms of acoustic quality and mechanical nature).

For example, here are some fragments of bass strings found on a lute by Raphael Mest in Linkoping (Sweden) followed by a German/Austrian iconography presumably from the middle of the 18th century:


Example of a 13 course d minor lute equipped with demifilè basses wound on a gut core considering all the historical information


On the Gallichon, we found this interesting iconography of German origin dating back to the mid-eighteenth century that, together with general considerations on the construction characteristics of the instrument, strongly suggest the use of close wound basses on a silk core (as already used on the 6-courses Spanish guitar), a hypothesis supported by our practical tests:



Historical documentation and French iconography bear witness to the use of wound basses on silk cores (Baud, 1797-98, Versailles) as well as demifilè, presumably on gut cores:

(Note the strings of the violin behind the harp: 4th wound in silver, and three gut strings)

At the end of the eighteenth century the demì strings went into disuse both because of the disappearance of the specific instruments that used them (viola bass, 5-course guitar, lute, etc.) and because they were replaced, in the plucked instruments, by those of type 1, wound on a silk core, that led to the appearance of the simple 6-string guitar:

Example of wound bass strings on silk cores, for 6-course Spanish guitar, dated back to 1810-12



Contrary to common belief, the demifilèe strings were not strings designed to have a ‘transition’ sound between the upper nude gut strings and the following close wound basses. To achieve this, a normal close wound string with a core-to-metal wire ratio in favour of the core would have been sufficient. The real reason is of a technological nature: research into 18th century wire technology has brought to light the fact that at that time they were not able to make wires so thin as to be able to access the close winding (for example, the thinnest gauge on the Creyseul scale, mid-18th century, concerning the gauge of wire for harpsichord is No. 12, equal to about 0.15 mm). See also on this subject: James Grassineau: “A musical Dictionary” London 1740).

The solution of covering a core by spacing the metal wire brilliantly solved the problem, but introduced a new one linked to the potential difficulties of conducting the bow and to the fragility of the metal winding at the nut.

Type 3 strings:

It is supposed that they were also used during the eighteenth century (G.B. Forqueray in his letter of 1768 explains to Prince Wilhelm that the lower strings of the viola bass should never be made double-covered but with simple winding: this is a clear indication that the double-covered strings were still known/used in those days); this means that, perhaps, they were a strategic solution for those particular bowed instruments characterized by having a very short vibrating length in relation to their tuning.

To cite, for example, the Violoncello/Viola da Spalla but, to be more sure, also the 5th low-B string added to the Double Bass in the late 19th century.


Vivi felice

How to correctly install gut strings in order to avoid breakages and at the same time assuring a fast and stable intonation

At times here in Aquila we are told: “I installed the first string and it broke, so I tried with a second one and it ended up the same way. I have been playing the [violin/viola/cello/gamba] in the last thirty years and I sure know how to install a string…


But being expert musicians and performers is enough to be considered expert installers of gut strings as well?


Critical characteristics of gut strings

As a matter of fact, due to its natural origin, at times a gut string can present a problem: in this case we talk about defective strings.

A string can be called defective when:

  1. it has been excessively polished: at touch and at sight the string may appear good and perfectly smooth, but in fact the external fibers have been excessively damaged, so, little after its installation, the broken fibers will raise from its surface as tiny hairs.
  2. it has very small whitish marks (fat spots) on the inside: such strings tend to break during the initial tuning
  3. it suddenly breaks once installed, far from its constraint points (bridge and nut)

A gut string in itself is very  strong to traction, but it also has some weak points:

  1. the material is not hard, so it suffers from potential sliding or contact points that are even minimally sharp (sharp edges)
  2. it easily absorbs humidity, so in humid environments the string becomes less compact, softer and therefore gets even more delicate on the sliding points
  3. it leads to high friction on contact points, at times it squeezes on the nut and bridge slots, or it may not slide smoothly.

Common solutions, like applying some graphite on the nut grooves, are pretty useless if the slots have not been appropriately created following the criterions suitable for gut strings, like in these examples:

The most important things to be observed, is that the slots are slightly cut and they never have clear bending points, and lastly that the nut is mirror-polished. Only at this point using graphite on the grooves becomes truly effective.

The historical essays, such as Thomas Mace’s Musik’s Monument (London 1676), suggest how the nut of a Lute should be prepared in order to avoid breakages and obtain tuning stability:

Finally, iconographic sources of the XVII century often show a particular nautical knot, called Bowline, that divides in half the traction of the string in two distinct points at the hole on the tailpiece (such use can be limited to the first and highest pitched string)

This is how to tie a Bowline knot:

There are also some other best practices to follow:

  1. tune the string keeping it out of the nut slot and, for bowed instruments, every now and then lifting the string from the bridge: this prevents the sliding on friction points, and assures an even tension on both sides of the constraint points. Put back the string in its slot only once tuned (or very near to its final tuning);
  2. Once in a while, it’s good practice to gently pull the string at half of its length, in order to unload its not recoverable elasticity and at the same time clamping it on its constraint points (this way the string will be almost immediately ready to be played);
  3. Put the string in tension slowly: the material needs time to reach its final state of stretching;
  4. The portion of the string wound on the peg should be as small as possible, making sure that on the first loop the string passes on top of itself, and then closing the spirals without further overlaps: see the indications of Thomas Mace on Musik’s Monument (London 1676).


The following videos summarize all the above mentioned recommendations:

Vivi felice


Mimmo Peruffo

Equal tension/ equal feel: some useful information

Equal tension/ equal feel

In this last decade, the so-called equal tension setting has grown very popular among many players of historical bowed instruments, with the belief that such setting is the exact scientific interpretation of what was being done in the past (and what has been found on some historical documents, especially regarding the Lute): strings must all have the same ‘tactile sensation/equal feel’ of tension.

Physics can prove mathematically that strings that show the same deviation gradient, when an identical weight is applied at the same distance from the bridge, will also have the same tension expressed in Kg (the same deviation gradient produce also an equal feel of tension under the fingers).

What has not been considered, though, is the fact that this mathematical relationship is true only when strings are already in their final state of traction, while it proves to be false if the theorical diameters are calculated using the same value of tension in the Mersenne-Tyler string formula, like most of the equal tension supporters do nowadays.

Huggins, in the late XIX century, was already aware of this difference (just like the count Riccati in 1760).

This is what really happens: when undergoing the same weight, the thinner strings, in percentage, will experience a higher thinning as compared to the thicker ones.

In other words, once they are set into their final state of traction (i.e. intonation), each string will get thinner by a percentage that depends on the twisting ratio and how it was realized (high twist/low twist/roped etc) and expecially its Working Index into the instrument (the FL product).

Such percentage will be maximum for the high-pitched thinner strings (i.e. chantarelles), while it will be gradually lower on the thicker ones .

If the string formula is then applied to the new diameters measured once the strings reach the final tuning (and therefore they are in their final state of traction/tuning), it will be observed that tensions will follow an inverse scalar profile, and also the tactile sensation/feel of tension will necessarily feel reversed as well (minimum on thinner strings, maximum on the thicker ones).

We therefore physically performed all the tests as described by Di Colco, Mozart and Mersenne, contradicting the results that apparently seemed to confirm the “equal tension” hypothesis using the Mersenne/Tyler string formula.

Mersenne itself not only wrote that no player of his time followed his indications, but also introduced a 1/16 corrective coefficient to the string formula, without giving any explanation, and causing some criticism (for example see Daniello Bartoli, 1692).

Attanasio Kircher (“Preludium1”, 1650) provides the number of gut casings needed to make Roman Violon strings:

Est hic Romae Chelys maior, quàm Violone vulgo vocant pentachorda, cuius maior chorda consesta est ex 200 intestinis. Secunda ex 180. Tertia ex 100. Quarta ex 50. Quinta denique ex 30. (19)

These details are very interesting and unique because they define the number of guts to be used to make the strings for this large instrument.

To verify the tension profile from other historical information we know that with three  whole unsplit lamb guts we obtain an average diameter of 0.70 mm (See De Lalande and Count Riccati) . The following is obtained by simple proportion:

1: 2.21 mm (30 guts)

2: 2.85 mm (50 guts)

3: 4.04 mm (100 guts)

4: 5.42 mm (180 guts)

5: 5.71 mm (200 guts)


The Chelys Maior is tuned as follows: E, A, DD, GG, (and lastly FF)

Let’s calculate the tensions considering a ‘Roman’ pitch of 392 Hz and a vibrating length – assumed by us –  of 90 cm. This is the data obtained:

1:  E – 35.50 Kg

2:  A – 26.31 Kg

3:  D – 23.54 Kg

4:  G – 18.88 Kg

5:  F  – 16.64 Kg


The tension profile has a scalar pattern: this is a direct example from the 17th century that demonstrates the scalarity of the tension expressed in Kg. By practical test this tension profile is also very close to an equal feel.

Unfortunately, none of today’s supporters of the equal tension, to the best of our knowledge, has ever done verification tests on what was stated on such documents, therefore trusting blindly what has been written.

As a conclusion, to recreate an “equal feel” setting, the theoretical calculation by the string formula must consider a certain degree of scalar tension.

When calculating our strings, we consider the correct scalar gradient: that’s why we are able to offer “equal feel” settings as they were used in the past, and that’s also the reason why we decided not to prepare “equal tension” settings by the string formula that have no real historical support and create disadvantages to a good musical performances, as Huggings and count Riccati already underlined in the XVIII and late XIX century.

We suggest to inform all customers about this topic, in order to finally clarify this point and avoid the practical difficulties encountered recently when calculating existent string settings.

To know more on this topic:


Vivi felice

Mimmo Peruffo

CD and CDL type basses for Lute and Baroque Guitar: main features, fields of use and correct installation procedure

Before approximately 1660, the lower strings in both plucked and bowed musical instruments were made in pure gut.

Up to this date there are two theories on this: the first believes that the gut strings were twisted in imitation of ropes used in the navy (increase in elasticity), while the second believes that the gut used for the basses was loaded using tanning techniques and then twisted.

We support this second option, that led us to produce the C type loaded gut strings, the production of which is currently still suspended.

Therefore, to solve this inconvenience, we designed the CD and CDL synthetic loaded strings (suitable only for plucked instruments).


CD strings

The CD type strings are synthetic strings used on the lower and medium basses on Lute and Baroque Guitar, characterized by a high standardized specific weight, achieved by loading  the synthetic material with metallic copper powder during the extrusion phase.

The surface is similar to the one of a rectified natural gut. The strings have a percussive and vocal tone, however their sound is full and blends perfectly with the paired string in octave. The working tensions remain unchanged compared to the usual playing habits.

The strings have an excellent tuning stability; they replace the modern wound strings that are too bright to fit the real nature of the Lute.

The CD type strings are also recommended for basses on short double-necks (like the  Liuti attiorbati or Archlutes, and the Swan Neck Lutes in minor D with max length = 105 cm)

The CD diameters thinner than 115 cm have only been partially loaded, in order to work best on the 5th course of the Lute and the 4th and 5th courses of the Baroque Guitar.


CDL strings

These type of strings are partially loaded basses with a length of 150 cm, specifically designed for basses with diapasons between 115 and 135 cm; an example are the historical Archlutes and the non-historical Theorbos with medium and short diapasons (suitable for travelling, and more common nowadays).

This is our answer to the inappropriate use of wound strings as basses on these types of instruments.

We restricted the length to 150 cm in order to avoid the use of such strings as basses on historical Theorbos (the correct strings for these intruments are gut strings or the synthetic NGE strings).

Please note: the human ear has a poor sensibility to the lower frequencies, so that on short distances one might think that these kind of strings will not have a sufficient acoustic energy as compared to wound strings that are perceived as more brilliant thanks to their harmonic richness (see the ‘Phon curves’). However the science of Phonometry shows that the lower frequencies are not dampened by long distances or sound-absorbing elements such as people, chairs or curtains. On the other hand, higher frequencies are greatly absorbed. As a result, a Theorbo using wound strings will not perform well on distances or sound-absorbing elements, while our CDL type basses will still sound great.


The correct installation

Both CD and CDL types are made with a synthetic elastomer that is characterized by the fact that it does not slide (that’s why elastomers are used for the soles of shoes). This implies that the common installing procedure does not work as expected, and might lead to unexpected breakages of the string: as a matter of fact, the poor sliding of the material  leads to a higher tension in the portion between peg and nut as compared to the tension between nut and bridge.

The CD type is very resistant in itself: just as an example, a 145CD string will break to a linear traction of 12 kg.

The correct procedure expects that the string, once fixed on the peg, must be kept constantly out of the nut groove during the whole initial tuning process, and it must be put back in the groove only once it has been pulled by hands and tuned up to the desired note.

This way the tension between peg and nut is the same as the one between nut and bridge, granting a high tuning stability and absence of breakages.

Using lubricants/graphite on the grooves of the nut has not proved to give appreciable benefits.

Corde NNG

NNG Strings: improvements introduced starting from October/November 2018

On this type of strings, there have been a few reports of the following problems:

  1. episodes of breakages on gauges 36-46 NNG
  2. NNG chanterelles (36-46 NNG) have less ‘silvering’ sounds compared to those made with gut
  3. the thicker NNG strings have more sound in itself as compared to those in gut, but they can’t substitute the wound strings on certain positions (5th course in Reinessance Lutes, lower octaves, 6th and 7th of theorbos of big dimensions)

In order to successfully resolve the above-mentioned issues 1 and 2, instead of using pure Nylgut, we introduced a new blend of Nylgut with a low percentage of our Sugar polymer, that produces a sound closer to gut, providing at the same time an increase in the strength of the string.

In gauges greater than 79 NNG instead – see above point 3 – the Nylgut has been replaced with our bioplastic called Sugar, that has the same specific weight and color of Nylgut. Thanks to this replacement, the sound has greatly improved, becoming comparable with aluminium wound strings. This improvement has been extended up to the 112 NNG.

It should be noted that Sugar allows better acoustic performances also compared to the CD strings, in gauges from 75 CD to 110 CD.

Comparative tests showed that CD strings, even if they are made with Nylgut loaded with metals, have a rounder sound compared to an NNG with equivalent gauge.

Corde NNG