Construction & Materials
Timber selection
The importance of soundboard spruce
Glues
Varnishing and finishing
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The process of finding the highest quality tonewoods for my instruments is a constant and often tedious process. Each piece requires specific characteristics that contribute to the sound, stability and longevity of the instrument. Not only is the beauty of a particular wood important, but also the physical properties of each species, the part of the tree from which it was cut, and most importantly, the method of cutting, which is critical to stability.
I am naturally drawn to wood and therefore this constant search for the most suitable and beautiful pieces is not a chore, but a very enjoyable activity that has taken me to many parts of Europe in search of the highest quality wood. Since my beginnings as a luthier I have stocked up on wood, so that today I have a large supply of beautiful, rare and well-seasoned European and tropical tonewoods to use for my instruments for many years to come.
Although I strive to use the most appropriate wood spices for each instrument based on historical models, since discovering and studying the inventory of musical instruments of Raymund Fugger (1528-1569), 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, including 141 lutes. These come in all shapes and sizes and in a wide variety of materials, both European and exotic. In the latter category we find lutes made of sandalwood, ebony, pernambuco, whalebone and bamboo (Canna d'India), to name but a few. This demonstrates that instrument makers of the time were quite open to experimenting with materials that were considered very exotic, and that they probably used all available woods and materials to make precious instruments for their wealthy clients.
Knowing these facts has fundamentally changed my mind about the range of woods I currently use for my instruments, and the woods I would like to use in the future. Since the old luthiers were open-minded and innovative when it came to materials, I have no regrets about imitating that attitude five centuries later.
European and American tonewood dealers have long employed a marketing strategy that misleads not only instrument buyers but also luthiers. They classify their spruce tops into arbitrary grades (Master, AAA, AA, etc.) based solely on aesthetics, with no relation to sound quality. This approach has led many in the field—builders, sellers, and buyers alike—to believe that tightly ringed, evenly colored spruce is inherently superior and produces better sound. Nothing could be further from the truth. These are purely visual characteristics that have no bearing on acoustics. While the aesthetic appeal of close-grained spruce is debatable, its supposed sonic superiority is entirely unfounded. In fact, if we look at the work of the great lute and violin makers of the Golden Age, we find the opposite trend: they almost always used medium- to wide-grained spruce.
What truly matters for sound and stability is the straightness of the fibers (which should not be confused with the annual rings), the precision of quarter-cutting, the weight-to-mass ratio, and several other factors that are too complex to summarize briefly. If tonewood manufacturers prioritized optimal acoustic properties when cutting the wood, the percentage of waste would be much higher, making the process far less profitable.
Thanks to extensive testing and experimentation, I have learned how to select the right spruce to achieve the sound I seek for each instrument. For smaller instruments, I personally split and machine my soundboards from large billets of the highest-quality, straight-grained spruce, ensuring full control over the process. For larger instruments, I rely on a few highly knowledgeable dealers who understand my requirements and occasionally source pieces that meet my rigorous standards. Even so, I end up rejecting about 75% of what they offer me.
Fortunately, my continuous search has yielded results, and I have accumulated a sufficient supply to last for many years. Yet, I remain on the lookout for that rare and fundamental resource—the very essence of great sound.
Hot hide glue is my primary adhesive and is used for most of the joints in my instruments. It is the oldest glue known to mankind and remains superior to modern alternatives in many ways. It forms bonds as strong as those of modern glues while offering the advantage of complete reversibility.
One drawback is that it must be applied hot to work properly, and the joints must be assembled quickly before the glue loses its strength. Another limitation is its susceptibility to failure in extreme humidity, both high and low.
The other glue I use is fish glue, which, as the name implies, is made from fish skin and bones. It is essentially the same as hide glue but can be applied at room temperature. From my tests, it is just as strong as hot hide glue but is less sensitive to moisture. That said, I currently use it only for joints that do not require the highest tensile strength.
I use traditional linseed oil varnish for the bodies and backs of my instruments. Made from a mixture of linseed oil and various resins, this type of varnish was used on lutes and violin-family instruments from the Renaissance through the Baroque period.
Due to the influence of contemporary classical guitar-making techniques, the much more modern method of French polishing is too often applied to modern lutes, vihuelas, and Baroque guitars. However, this spirit varnish technique has no historical basis or relevance in the context of Renaissance and Baroque instruments.
The main reason for using shellac (French polish) is that its application is less labor-intensive, whereas oil varnish takes much longer to dry—yet both can produce similar visual results. The key advantage of oil varnish is that, when applied in numerous very thin coats over an extended period, it creates a much harder and more durable finish.
Instruments that develop varnish issues after only a few years are typically finished with just two or three thick coats that never fully dry. To avoid this, I apply 15 to 20 very thin coats of traditional oil varnish, following a recipe from the early 17th century. Each coat is allowed to dry thoroughly before the next is applied. Depending on weather conditions, this process can take anywhere from 7 to 14 days. Though highly labor-intensive, it is the only method that ensures maximum transparency and durability of the finish.