Like moths, beetles and sundry diseases, fungi have a bad reputation when it comes to trees. But two species of fungi may also help unlock the secrets of the great 18th-century Italian violins, say researchers.
Science Daily reports that Swiss bioengineer Francis W. M. R. Schwarze has found that by treating the wood used in a violin with special fungi, it becomes lower in density and higher in elasticity. This has a direct influence on the violin's acoustic properties, and brings it closer to the instruments built by the famous Cremonese maker Antonio Stradivari.
Stradivari is believed to have unwittingly benefitted from a prolonged cold period – roughly between 1645 and 1715. This made trees grow more slowly and evenly. The harvested wood was thus lower in density and higher in elasticity, imparting its characteristic brilliance.
Two specific species of fungi – Physisporinus vitreus and Xylaria longipes – decay Norway spruce and sycamore, two kinds of wood used in violins, said Schwarze. But before the decomposing wood is actually put to use in a violin it is treated with ethylene oxide gas, which causes the fungal growth to stop.
Schwarze worked with two violin-makers in his experiment, Martin Schleske and Michael Rhonheimer. In 2009, their fungi-treated instruments were played in a blind, behind-the-curtain test alongside a genuine Stradivarius from 1717. British violinist Matthew Trusler performed on all of the instruments. After the performance, a jury of experts and the majority of an audience thought that a fungi violin was the actual Strad.
Numerous theories have been advanced over the decades to explain the supposedly superior qualities of Strads and Guarneris. Some researchers have argued that the logs providing the wood for the violins had been stored floating in water, thus increasing their permeability. Others have suggested that the violins benefited from a special varnish. Of course, some musicians and violin-makers detest the notion that such extraordinary sound could be simply a matter of chemistry and not craftsmanship.
Nevertheless, understanding the chemistry of this process could lead to improvements in the production of modern violins, so they could sound a million dollars without costing it.
Such tests are always subjective, said Schwarze of the blind test. “There is no clear-cut, scientific method for measuring tonal quality."