The conservation of historical keyboard instruments:
to play or to preserve?
This paper may be quoted in part or in its entirety with permission from the author.
Ideally the modern keyboard instrument restorer would be trained in the conservation of wood, metal, leather, ivory, bone, cloth, paper, and in painted and varnished surfaces. He should have a good grounding in chemistry and physics (especially acoustics) and be conversant with analytical techniques such as X-rays, X-ray fluorescence, gas chromatography, mass spectrometry, and so on. In no other field is a restorer or conservator expected to have some knowledge of as many different fields in order to carry out the preservation of the objects given to him for treatment. As though this is not enough it is also essential that he must be a part-time musicologist and musician, and must know at least something of the history of art and of furniture design. How can an instrument restorer do his job properly on a scientific and historical basis unless he has a training in all of these fields? The fact is, of course, that there is probably not a musical instrument restorer or conservator in the world who is sufficiently well versed in all of these different aspects that he could carry out a restoration that would not be faulted by a specialist in one or more of these fields.
An associated problem is that there is an almost total lack of fundamental research providing information on the effect of the operations that we normally carry out on the instruments we are restoring. What is the effect of the solvents used to remove old varnish and dirt from a harpsichord soundboard on the acoustical and musical properties of the soundboard? How does filling cracks and wood-worm holes affect the soundboard? Normal conservation techniques for cloth and leather do not normally require that these materials continue in active use. Are the usual techniques of cloth and leather conservation therefore applicable to these materials when used in keyboard instruments where they are required to perform their original mechanical functions? What is the effect of ageing on a wood and how long can we reasonably expect an instrument to be able to withstand string tension? Are the acoustical properties of a soundboard time dependant? If so does a soundboard sound better or worse as time goes by? - does it reach a peak? These are but a few of the questions that should be answered before any restorer lifts a knife or chisel and begins the restoration of a keyboard instrument.
One of the most obvious reasons for restoring a musical instrument is that the sound and feel under the fingers of a well-restored musical instrument will have an effect on the interpretation of the music written for it. Basically the purpose of restoration boils down to discovering the relationship between the music and the instrument. Only a few years ago harpsichords strung with steel and phosphor-bronze strings, with replacement jacks with regulating screws and leather or plastic plectra, and with modern felts in the keyboards, were accepted without question as sounding and playing as they did in the 17th and 18th centuries.
But in recent years we have become much more demanding and critical of keyboard restoration. The importance of using soft wire for stringing harpsichords, spinets, virginals and clavichords is only now being realised. We want to know if the depth of touch of the keys is correct and are now discovering that the depth of touch is not the same in all regional schools of building. What is the plucking order? what is the angle of the plectrum to the horizontal? - how arc the dampers cut? — what is the correct length of the plectra in each register? what is the lost motion of the keylever before the first register plucks and after the last register has plucked? These are but a few of the questions facing the modern keyboard restorer.
The problem for the restorer is not so much that he has to re-string the instrument with soft strings and re-regulate it along historical lines, but that there arc no longer any instruments left as primary documents which can tell us what actual size of string to use, and what the depth of touch, plucking order, plectrum length and angle, etc., should be.
Further, I am absolutely sure that we will become even more sophisticated and demanding in the future. Even the most conscientious modern restorer faced with the restoration of an instrument with original keyboard cloths, jacks, plectra, dampers and strings, who carefully records and documents all of the features that are currently felt to be of importance, will probably fail to record or observe details that will be of interest to future generations. A few years ago I visited a major European Museum which publicly professes a scientific approach to restoration and conservation and which had just bought an important French harpsichord. Although the instrument had only been in the hands of the museum a few weeks it was already in pieces, the baseboard had been removed and the keyboards had been stripped down and the original keyboard cloths had been removed. The original depth of touch had not been recorded, the plucking order had not been noted and the adjustment of the registers which would have given the original plectrum length had been altered.
This is but one of a long catalogue of horror stories I could quote. The fact is that we are destroying primary evidence at an alarming rate. Despite our attempts to ensure reversibility, we are constantly having to carry out irreversible operations and evidence not only of the stringing, mechanical operation of the instruments, but also evidence of the construction and decoration of these instruments is being lost at an accelerating rate.
What has led us to the present state of musical instrument restoration? Why are we destroying evidence on these instruments as though there were an endless supply of them from which to draw more information, should it accidentally be lost from the one we are working on? What are the basic assumptions and the philosophy of restoration that has given rise to the present state of restoration? It is what I call “The Existentialist Philosophy of Restoration”. The essential tenet of this philosophy is “If it exists, restore it”! The only book dealing specifically with the preservation and restoration of musical instruments puts this succinctly: “Where possible the restoration of a deteriorated instrument is commendable”. This attitude is basic and unquestioned by many museums, private collectors, restorers and conservators. Underlying this attitude is the belief, which I feel to be mistaken, that because an instrument is old and was built in the historical period it must sound better than a modern copy. Also there is the mistaken belief that the sound of any given instrument is representative of its builder's usual work. But there are good and bad sounding Ruckers instruments - I know this from personal experience. The beautiful 1755 Kirkman double-manual harpsichord in the Russell Collection, Edinburgh is a fine piece of furniture, but is disappointing as a musical instrument in comparison with other examples of Kirkman's work. Thus even for instruments in sound condition there is no guarantee that they will be either representative or musically instructive after restoration.
The situation for instruments that are in a damaged or fragile conditions is even more problematical. It is pointless to restore an instrument to a pitch below that for which it was designed, or to use strings thinner than those originally intended in order to prevent too great a tension on the structure of the instrument. Doing so falsifies the sound of the instrument and the music that will be made on it. A decision must be made: either the instrument is able to withstand the string tension at the required pitch and with the correct string gauges, or it cannot. If it can, then restoration may be considered, although not necessarily eventually carried out. If it cannot then it should not be restored to playing condition. Many instruments have been damaged or altered and restoration to playing condition means that some or all of the original scalings, plucking points, structural, mechanical and acoustical parts have to be reconstructed. These reconstructions are often based on insufficient or hypothetical evidence from other instruments. I say: “What is the point of reconstructing half an instrument unless there is a good certainty that the final sound and touch of the instrument are representative?”.
Instruments of extreme old age or exceptional rarity are also not immediate candidates for restoration. The German clavicytherium made about 1480 and now in the Royal College of Music, London is too fragile and delicate to withstand string tension. The 1638 Ioannes Ruckers double-manual harpsichord in the Russell Collection, Edinburgh is unique: it is the only 'transposing' harpsichord in the world which still has its original unaligned keyboards. It is in sound physical condition and could withstand string tension easily, but it retains most of its original keyboard cloths which have been attacked by bacterial or fungal activity leaving the fibres weak and brittle. A restoration to playing condition would result in the destruction of these cloths from mechanical damage, or they would have to be removed in the restoration. Many of the other original features of this harpsichord would also be lost or altered in an eventual restoration. When I was Curator of the Russell Collection, I therefore took the decision not to restore this original and unique instrument.
To summarize the present situation briefly: the process of restoration of musical instruments is destroying evidence about the very objects that we are supposed to be conserving. That all processes carried out in musical instrument restorations should be reversible is a commendable ideal, but it is impossible to achieve in practice. Instruments should be restored to the most recent state of legitimate musical use, but doing so may involve much conjecture and arbitrary re-construction, and it is often the case that this state may have been introduced in the historical period by someone who was unskilled or unenlightened about what he was doing. Restoration to this state would be musically unsatisfactory and restoration to any previous state would involve many irreversible operations to be carried out and the destruction of much of the history of the instrument. Many instruments are too fragile, too old, or are unique examples of their kind and restoration of them is therefore out of the question.
What is the solution to all of these problems? Can we go forward and learn from these historical instruments without restoring them and without destroying evidence on the instruments which are, after all, the primary documents? One of the suggestions that has been put forward is that copies be made of the instruments, rather than carrying out the restoration of the originals. There are many good reasons for doing this. The copy will be made of new wood, and there will be no danger that it will be damaged by the string tension. Experiments with stringing, pitch, voicing, etc. can be carried out on the copy without any chance of damage to the original. The copy can be played an unlimited amount without any restrictions or worry about over-use. If the original has been altered, the copy can be made in the original state of the instrument and any reconstruction can be made and then altered later in the light of new evidence without any harm to the original. Probably the copy will sound more like the historical instrument did when new than the original would if restored. Objections have been made to this suggestion by people saying that copies made by different builders each sound different. However, despite the fact that the copies are usually described as 'exact', I know of no copy that has been made on a truly scientific basis. The contours of the soundboard thickness have never, as far as I know, ever been copied exactly, and no one has refined this to copying the soundboard stiffness which is actually the acoustical parameter which is essential to achieve a similar sound in the copy to that in the original.
Carried to its logical extreme, the making of copies of historical instruments would mean that our museums and collections would become galleries filled with modern reproductions. This would be as unacceptable as if our great painting galleries put all the originals into storage and out of harm’s way and exhibited copies instead. Nonetheless the acoustical and musical function that a musical instrument has to serve does argue in favour of the making of copies in some of those cases discussed above.
Also, closely related to the making of copies is that of making replacement actions for some instruments. Because it is really the mechanical part of a keyboard instrument that suffers from over use, the making of a new set of keyboards, and jacks or piano hammers allows a popular instrument to be used as much as desired. At the Russell Collection in Edinburgh, we have decided to restore our 1608 Andreas Ruckers double-manual harpsichord with a modern set of keyboards and jacks. We have also decided to make a replacement action for the unique early-English grand piano of 1772 by Americus Backers. The Ringve Museum, Trondheim, in Norway has decided to commission a replacement action for their 1783 fortepiano by Andreas Stein. Replacement actions are especially important in early pianos since the original actions can be preserved separately with their original (if worn) leathers and action cloths which would otherwise have to be replaced.
Finally I would like to discuss briefly two-restoration projects which I am faced with at the moment where it is not at all clear to me how (or if) the restoration should proceed. The first of these is an Andreas Ruckers single-manual harpsichord of 1609 belonging to Prof. Peter Williams. This instrument was originally one of the usual 6-voet single-manual harpsichords with a 1 x 8', 1 x 4' disposition and a compass of C/E to c3. Between 1609 and about 1770 it was given a number of minor alterations. By about 1770 it had found its way to England where the case was widened, new keyboards and action were made for it, and it was given a 2 x 8', 1 x 4' disposition and a compass of A1 to d3. This state must have been musically very unsatisfactory. The treble scalings must have been very short and the ends of the bridge extensions for the new large compass would have sat on the soundboard directly above the solid liners. The bass strings had to sound a minor third lower than the original note C intended by Ruckers, and so would have been far too short for the new lower note. It was a case of trying to squeeze a quart into a pint pot.
Probably because this state was musically unacceptable the Dolmetsch firm earlier this century reduced the compass to C to d3 with a new set of keys but using the old keyframe. This enabled the ends of the bridge extensions to be removed and returned the pitch of the lowest string to near that originally intended. Restoring the most recent historical state would return the instrument to its 1770 state. But is this a legitimate musical state? What should one do when the most recent historical state is clearly musically unacceptable, and restoration to an earlier state would destroy evidence of the history of the instrument. The solution that I have proposed to the owner is to leave the compass as it is and alter the Dolmetsch nut positions to give scalings and plucking points typical of other well-designed English instruments of the late 18th century.
The second problematical instrument is a large German clavichord with a 5-octave compass from F1 to f3. It is possibly the only surviving instrument to have survived by I. C. Gerlach (1756) of Hamburg. The instrument is of an extremely high standard of workmanship and is of a beautiful and sophisticated design. It appears to have been untouched since it was built and strung by Gerlach. Everything about it is original including such ephemera as the keyboard cloths, the balance pin cords and linen cloths, guide pins of horn, and there are also many tuning pins wrapped with their original strings. If the instrument were to be restored everything that I would touch would be irreversibly altered and all traces of Gerlach's handling of these ephemera would be lost. I find the restoration of this extremely fine and completely untouched instrument a very daunting prospect. I could, of course, measure the original depth of touch of the keys before the action cloths are removed for cleaning. I would desperately like to know the diameters of the original strings on the tuning pins since their gauge numbers were marked on the instrument by Gerlach. We would learn a lot by restoring the instrument. But we would lose a lot as well. Shouldn't completely untouched instruments such as this be left as a heritage for future generations to study? Let's at least postpone the restoration of this instrument until the results of the fundamental research on the effect of what we are doing is known. How will the acoustics of the soundboard be affected by cleaning it? What is the effect on their mechanical properties of cleaning the action cloths, and what is the effect on the mechanical and acoustical properties of the old wire on removing it from the tuning pins? In short, how do the multiplicity of operations which we presently carry out blindly affect the very object we are attempting to preserve? The acoustical and mechanical properties of musical instruments impose conditions not found in other fields of conservation and restoration. And the almost total lack of fundamental research on the effect of the operations we normally regard as routine on these properties, coupled with the scarcity of untouched virgin instruments, requires us to re-think our approach to the restoration of musical instruments, and to provide a heritage of unrestored instruments for study by future generations.
- Written by Grant O'Brien
This is the text of a paper that was presented at a conference in Venice Conservazione restauro e riuso degli strumenti musicali antichi: per una Carte Europea del Restauro. Convengno internazionale di studi. (Fondazione Levi Venezia per l’Anno Europeo della Musica 1985). It was published in 1987: Per una carta europea del restauro. Conservazione, restauro e riuso degli strumenti musicali anitichi, (Olschki, Florence, 1987) 291-8.
The CIMCIM webiste
See the sections on this site dealing with Consultations and Restorations. For further help to deal with any problems you may have please get in touch with me and I will try to help.
Go to the top of page
Some problems of restoration ethics in the restoration of a Franco-Flemish double-manual harpsichord