Construction & Materials
European and American tonewood dealers have developed a marketing strategy that has for a long time not only misled instrument buyers but also luthiers. It consists in categorising their spruce soundboards into grades (Master, AAA, AA, etc.) that do not have a relation to sound quality in any respect and are exclusively based on aesthetical grounds. This attitude has made believe the majority of people involved with making, selling and buying instruments that a narrow ringed, even coloured piece of spruce is the absolute best and will sound superior to any other. This cannot be further from the truth. Those are only exterior characteristics that have no relation to sound. The aesthetical superiority of narrow grained spruce may be discussed but its superiority in terms of sound are indefensible. If we take the work of the great lute and violin family makers of the golden age as an example, we will observe precisely a tendency to the contrary, using medium to wide grained spruce almost on every instance.
Of great importance to sound is the straightness of the fibres (not to be confused with growth rings), the precision on the cutting to the quarter, the weight to mass ratio and some other factors that are quite complex to explain briefly. Should tonewood spruce producers cut the wood properly to obtain the best sound, the percentage of waste would be much higher resulting in a less profitable bussines.
Thanks to the extensive testing and experimenting a have done in the past I am able to discern the right kind of spruce for the kind of sound I want for a certain instrument. My soundboards for smaller instruments are split and processed by myself from a big billet of the highest quality, very straight spruce, in order to be completely in control of the process. For bigger instruments, I rely on a couple of very knowledgeable dealers that know exactly what I am looking for and sometimes are able to find a few pieces for me that could meet my rigorous requirements. In spite of that, I still send back about 75 per cent of what they offer me!
Luckily the constant searching gives its fruits and I have managed to build enough stock for a few years use, but I always continue to search that scarce and primordial resource that will be the prime base and most important element towards a magnificent sound.
Hot hide glue is my main glue and it is used for the majority of joints on my instruments. This is the oldest glue known to man and still superior in many respects to modern alternatives. It can create as strong a joint as modern glues with the advantage of being completely reversible. One of its drawbacks is that in order for it to work correctly it should be applied hot and the joints should be assembled very quickly lest the glue may lose its strength. Another disadvantage is its susceptibility to fail in extreme high and low humidity conditions. Fish glue is the other glue I use and, as its name indicates, it is made from fish skin and bones. It is basically the same as hide glue but it can be applied at room temperature. According to the tests I have conducted, it is as strong as hot hide glue with the advantage of being less sensitive to humidity. In spite of this, I am presently only using it for joints that do not require the highest tensile strength.
Certain tropical timbers are best left without varnishing due to their high content of natural oils and extractives. These timbers usually produce a very appealing look just by polishing them and applying linseed oil and some sort of natural wax like carnauba or beeswax. This simple finish provides enough protection and can be easily refreshed by the owner of the instrument himself by applying a new thin layer of fresh wax (included with all my instruments made with these timbers) to the surface.
The process of finding the highest quality tonewoods for my instruments is a constant and oftentimes an arduous one. Every part requires specific characteristics that will contribute to the sound, stability and longevity of the instrument. Not only the beauty of a certain piece of wood will be of importance but also the intrinsic physical characteristics of each species, the part of the three it was cut from and most important of all the way it was cut, which is paramount I terms of stability.
I feel naturally attracted to wood and therefore this constant search for the most suitable and beautiful pieces is, instead of a chore, a very pleasant activity that has taken me to many parts of Europe looking for the highest quality timber. I have been stockpiling wood since my beginnings as a luthier and as a result, I now have an ample stock of beautiful, rare and well-seasoned European and tropical tonewoods for use on my instruments for many years to come.
Although I strive to use the most suitable wood spices for each instrument based on historical examples, since having discovered and studied the inventory of musical instruments of Raymund Fugger junior (1528-1569) from the year 1566, I have come to the conclusion that our ideas and perceptions about the materials used for instruments in the XVI Century are still very limited and conservative. This inventory lists the hundreds of instruments in his possession, amongst which, 141 lutes were listed. These come in all shapes and sizes and are made from a great diversity of materials, both European and exotic. Among the latter category, we find lutes made with sandalwood, ebony, pernambuco, whalebone and bamboo (Canna d'India) to name a few. This demonstrates that instrument makers of the time were quite open to experimenting with what at the time were considered very exotic materials and that they probably used whatever timbers and materials had available in order to make precious instruments for their wealthy customers.
The discovery of these facts has radically changed my mind about the scope of timbers I am presently using on my instruments and that I am willing to use in the future. If the old lutemakers were open-minded and innovative regarding materials, I should have no problem in imitating this attitude five centuries later.
The importance of soundboard spruce
Varnishing and finishing
I use traditional linseed oil varnish for the bodies and backs of my instruments. It is made mixing linseed oil with various resins and it is the kind of varnish that lutes (and violin family instruments) used from the Renaissance all through the Baroque periods. Due to classical guitar construction influence, the much more modern technique of French polishing is too often applied to modern lutes, vihuelas and baroque guitars. This technique of spirit varnishing has no place or meaning in the context of historical Renaissance and Baroque instruments.
The reason for its use comes from the fact that its application is much less labour intensive whilst oil varnish takes much more time to dry and both produce quite similar visual results. The great advantage of oil varnish is that it produces a much harder and resilient surface if applied in numerous very thin coats over a long period of time.
Instruments that develop varnish problems after only a few years of use are generally varnished in 2 to 3 thick layers that never really dry completely. In order to avoid this, I apply a number of 15 to 20 very thin coats of traditional oil varnish (made from an early XVII Century recipe), letting each one dry thoroughly before applying the next one. This process can take from one week to 14 days depending on weather conditions. It is a very labour intensive process but the only one that will assure the maximum transparency and toughness of the finish.