::An introduction to gut strings on the lute

 Historically, lutes were strung with gut, which gives a very different sound and feel from today's more frequent synthetic stringing. Lutenists wishing to hear their instrument's true voice should at least once try gut stringing, and the following guide explains how to do this.

 Our first step will be to work out whether it is possible to string our lute with gut at the pitch at which we want to play it. All gut strings break at more or less the same pitch on any given string length, irrespective of diameter; only the breaking tension varies. This may be counter-intuitive but is a fact that gives us a constant factor from which to calculate a working pitch. First we have to convert our string length (measured between the insides of bridge and nut) into meters: e.g. for a 60cm g' lute that will be 0.6, and then divide 240 (our above mentioned constant) by this number. The result is the frequency in Herz of the highest note to which we can tune a gut string at that string length. With the best quality strings it is a conservative estimate, leaving a safety margin of at least a semitone. For reference, the frequencies of the commonest top string notes are: a' above middle c': 440. g' sharp - 415; g' - 392; f' sharp - 370; f' - 349, e' - 329. Our 60cm lute gives us a frequency of 400 Hz, or a rather sharp g'.

 If the resulting figure says that our stringing ambitions are realistic, we now need to work out exactly which strings to use. The manufacturing processes and terminology used for modern gut strings are often not the same as those used for historical gut strings, about which we have little reliable information anyway. This guide follows the straightforward terminology used by Mimmo Peruffo, who has pioneered the recreation of various historical string types now widely used by professional players. Other manufacturers have their own string types and terminology, but the basic principles are few and present no problems once we have understood by what criteria we want to choose our strings.

:: Treble strings

 Treble strings are the thinnest, tightest and most used strings on a lute and require the maximum possible tensile strength. Therefore they are always made of low-twist plain gut, which simplifies selection. We just need to know what gauge and length we want, and then choose a finish. Gauges and lengths are discussed at the end of this leaflet. Finishes mean oiled versus varnished, rectified versus unrectified. Historically, only unrectified oiled strings were available. Oiled strings are cured in oil during manufacture (the finished strings do not feel oily!) and are considered by most players to have a better sound than varnished strings. However, varnished strings are less affected by climatic changes (which affect tuning stability) and are more resistant to extreme skin chemistry - though some players find that their fingers squeak on the varnish. If our sweaty fingers turn the wire on your wound strings black or green, we may be better off with varnished gut, otherwise we rather go for the oiled strings.

 Gut is a natural material with inherent irregularities. A finished string which is very irregular along its length will not fret in tune, therefore most strings are rectified mechanically as part of the manufacturing process, to remove any possible irregularities. Some surface fibres are cut during this process, so the resulting string is a little weaker, but because it is evenly round along its length it frets in tune. Unrectified strings are polished by hand, and can retain some irregularity. Their trueness can vary and some may not fret perfectly in tune, but they are stronger and last longer than rectified strings and their tone and sustain is unmatched by any other kind of string.

:: Mid-range strings

 For mid-range strings (3rd-4th courses on Renaissance lutes, 3rd-5th courses on Baroque lutes) we have a choice of plain gut or 'Venice' strings; the latter are indicated with a 'V' after the gauge number. Plain gut strings in these gauges are made from many strands of gut, with a higher amount of twist than the thinner ones, and are therefore called 'high twist'. This is done to give them flexibility, which in turn gives better intonation: if the strings are not flexible enough, the lateral displacement produced by fretting will cause the notes to go sharp. Venice strings are made with even more twist and are therefore more flexible; they have a brighter sound and fret better in tune than plain gut. They are more expensive but also extremely durable and their superior quality is clearly audible on gauges from about 0.8mm upwards, particularly on fretted courses. For thinner gauges and upper octaves of unfretted bass courses, regular high-twist gut is fine. We have the same choice of oiled or varnished finish, but these strings are always rectified so we do not need to specify this.

:: Bass strings

 Here we have a lot of choices. On a few instruments such as the six course lute, Venice strings will work well right down to the bass, producing a focused sound and longer sustain than regular plain gut strings. If we need lower notes on a relatively short string length we will need heavier strings, and here we meet the big problem in stringing a lute with gut. We want bass courses with a strong and focused sound but we cannot simply keep increasing for ever the thickness of the strings to achieve lower notes. A very thick plain gut string sounds dull, is too inflexible to fret in tune and feels unwieldy under the fingers (and would not pass through the bridge and peg holes of historical lutes). Assuming that such a string already has the maximum possible twist, the only option is to somehow increase its weight. Gut can be made denser by impregnating the raw material with metal salts (loaded strings), or a finished string can be made heavier by wrapping metal wire around it (wound strings). Loaded strings are the closest modern equivalent to the red basses we see in many 16th and early 17th century paintings. They are red-brown in colour, have a smooth finish and are significantly thinner than their plain gut equivalents. They are easy to pluck and fret, have a firm, focused sound, and sustain a little better than Venice strings. They are the best choice for unfretted courses, e.g. the lowest courses of baroque lutes. Because gut tends to absorb metal salts unevenly, some strings may suffer from intonation problems when fretted.

 Wound strings were not available until the 1660s and there is no evidence for their widespread use until the 18th century. Historical strings could be 'demi-filé', open-wound (literally 'half-wound'), with a gap between the spires as wide as the diameter of the wrapping wire, or close-wound, with the winding entirely covering the core. A close-wound string is heavier than a half-wound of the same gauge and therefore best for the lowest basses and/or shorter string lengths. The winding may be of silver for a brighter sound, or copper for a warmer sound. Wound on gut strings have a focused sound and a shorter sustain than modern wound on nylon strings.

:: Working out gauges and lengths

 To work out gauges we need to know a lute's string length(s), measured between the inside of nut and bridge, the note to which it is to be tuned (g', d', a, etc), and its pitch (A440, A415, etc). Note also whether each course is single or double, octave or unison strung. Ideally we need the tension of each string as well. String manufacturers Aquila Corde Armoniche (www.aquilacorde.com) offer an online string calculator on their website. If we type this information into the appropriate spaces, it will work out the gauges we need. Note that the different types of strings are all calculated by their plain gut equivalent, so if we work out the gauge we need for plain gut and then decide to have a Venice or loaded string instead, we can just keep the same number and add 'V' for Venice or 'C' for loaded. It is normal practice to reduce the tension across the lute as the strings become thicker; this gives a certain feeling of equal tension, which is desirable. A single top string should be appreciably tighter, about 50% than the individual strings of the second (double) course. From the second to the fifth courses, the tension should be slightly reduced with each successive course. From the fifth course downwards we can use the same tension on each course. If we do not know our string tension we can work it out from our lute's current stringing, irrespective of material, using the same online calculator and string conversion charts. Plain nylon string gauges (but not fluoro-carbon) can be converted to their equivalent gut gauges by multiplying them by 0.91: e.g., a 0.50mm nylon string is equivalent to a 0.45mm gut string. For those who do not know their lute's current stringing details, some specimen stringing lists are supplied at the end of this leaflet, for some common lute types at average tension. Those who do not have access to the web can obtain a reasonably priced string calculator from Bernd Kürschner (Obere Waldstrasse 20, D-65232 Taunusstein, Germany. Tel. +49 (0) 6128-6910). If we are still unable to work out the tension, most string dealers and makers will work it out for us: this information should always be kept in the case with our lute. To work out the total length needed we shall add together the sounding length of the string (bridge to nut), the length from the nut to the appropriate peg, plus around 10cm to allow for tying on the bridge and winding on the peg. The standard 120cm length is adequate for almost all lutes except archlute and theorbo diapasons.

:: Fitting, and caring for, gut strings

 We should be careful not to kink strings as we fit them: such kinks are weak points and may affect the sound. Otherwise, gut strings are easier to fit than nylon because they are less slippery. They will usually grip easily on the bridge, negating the need for multiple twists, knots or burnt nodules on the string ends. The easiest way to attach thin strings to the peg is to push about 2cm of string through the peg hole, twist the short end around the main length a couple of times, and then wind the string up on the peg. To avoid possible string jams and breakages, it is advisable to wind the string so that it does not press against the wall of the pegbox.

 The thinnest strings will last longer if we detune them by about a tone between playing sessions. They settle to pitch very quickly when tuned up again. We ought to make sure that nut grooves are smooth and well polished, lest strings fray at this point. Any hairs which sprout from the surface of a string should be cut off close (a nail clipper does the job quite well) because they deaden the sound of a string and may cause further unravelling. We can slightly improve a string's performance by first tying it on the bridge, rolling it between our fingers to introduce more twist (it must be rolled in the direction of the existing twist), then fixing it to the peg. The life of an unvarnished gut string may be prolonged by a very light coating of almond oil. We put a spot of oil on index finger and thumb and run the length of the string between them: it is a non-siccative oil so it should be imperceptibly fine.

by Lynda Sayce, with advice and assistance from Mimmo Peruffo and Ivo Magherini.