The Secret of the Stradivarius
Why the violins made by Antonio Stradivari in seventeenth-century Italy remain the most sought-after instruments ever produced -- and whether science can explain it
A Antonio Stradivari, the master luthier of Cremona, produced approximately 1,100 instruments between about 1666 and his death in 1737. Of these, around 650 survive -- roughly 500 violins and the remainder violas, cellos, and other instruments. These instruments command extraordinary prices at auction: a Stradivarius violin regularly sells for several million dollars, and some of the finest examples are valued at over fifteen million. Professional violinists who own or are loaned Stradivari instruments speak of their sound in terms that suggest the instruments possess qualities irreproducible by modern makers. The scientific investigation of whether this is true -- and if so, why -- has been ongoing for decades, with inconclusive results.
B The physical properties of the wood used by Stradivari have been the subject of sustained investigation. Analysis of the wood in surviving instruments has confirmed that it came from spruce and maple trees grown in the Italian Alps, and that these trees grew during the Late Maunder Minimum -- a period of reduced solar activity between approximately 1645 and 1715 that produced unusually cold summers and consequently denser, more uniform tree rings than are typically found. Some researchers have proposed that this exceptionally uniform wood may contribute to the instruments' acoustic properties, though others note that wood of comparable quality can be sourced today and point out that Stradivari's contemporaries working with the same materials did not produce instruments of equivalent reputation.
C A second line of investigation has focused on the chemical treatment of the wood. Analysis using techniques including X-ray fluorescence and infrared spectroscopy has revealed the presence of mineral salts -- including compounds of aluminium, calcium, and potassium -- in the wood of Stradivari instruments at concentrations not typically found in untreated wood. Some researchers have proposed that Stradivari or his contemporaries applied chemical solutions to the wood before instrument construction, perhaps as a preservative or to alter its acoustic properties. Others have suggested that the instruments may have been treated after construction, or that the mineral content reflects natural changes in the wood over centuries of use and storage.
D The varnish applied to Stradivari instruments has attracted perhaps the most attention of any single feature. Early investigations speculated that a secret varnish formula, now lost, might be the key to the instruments' sound. Detailed chemical analysis has found that the varnish is composed of materials -- drying oils, protein- based grounds, and mineral pigments -- that were commonly available in seventeenth-century Cremona and are not unusual by the standards of the period. The weight and composition of the varnish vary between instruments, and some researchers have suggested that the acoustic dampening effect of a thicker varnish layer may actually reduce the brilliance of an instrument's sound. The consensus view today is that the varnish, while aesthetically distinctive, is unlikely to be the primary determinant of the instruments' sonic character.
E Perhaps the most provocative contribution to the debate came from a series of double-blind listening tests conducted at a major international violin competition. Professional violinists, including several who owned or regularly played Stradivari instruments, were asked to play both Stradivari and modern instruments under conditions where neither the players nor the listeners could visually identify which instrument was being used. The majority of players could not reliably distinguish their preferred Stradivarius from a modern instrument made by a skilled contemporary maker. Some players actively preferred modern instruments. The results caused significant controversy and were challenged on methodological grounds by those who argued that the playing conditions -- a small hotel room rather than a concert hall -- did not replicate the conditions under which the instruments' differences would be most apparent.
F The question of whether Stradivari instruments are objectively superior to the best modern violins may ultimately be unanswerable, not because the science is inadequate, but because the category 'superior' has no single objective definition in this context. Sound is experienced subjectively; what one listener hears as brilliance another hears as harshness, and what one player feels as responsiveness another experiences as unpredictability. The cultural prestige attached to Stradivari instruments -- and the extraordinary prices they command -- almost certainly influence how listeners and players experience them. The finest modern makers produce instruments that are acoustically indistinguishable from Stradivari violins under controlled conditions. Whether this matters to the musicians who play them, or to the audiences who hear them, may depend less on the physics of sound than on the human meanings attached to the objects that produce it.