Treatment with Fungi Makes a Modern Violin Sound Like a Stradiavarius

Low
density, high speed of sound and a high modulus of elasticity – these qualities
are essential for ideal violin tone wood. In the late 17th and early 18th
century the famous violin maker Antonio Stradivari used a special wood that had
grown in the cold period between 1645 and 1715. In the long winters and the
cool summers, the wood grew especially slowly and evenly, creating low density
and a high modulus of elasticity. Until now, modern violin makers could only
dream of wood with such tonal qualities.

Professor Schwarze’s developments could soon make similarly good wood
available for violin making. He discovered two species of fungi (Physisporinus vitreus and Xylaria longipes),
which decay Norway spruce and sycamore – the two important kinds of wood used for
violin making – to such an extent that their tonal quality is improved. “Normally
fungi reduce the density of the wood, but at the same time they unfortunately reduce
the speed with which the sound waves travel through the wood,” the researcher
explained. “The unique feature of these fungi is that they gradually degrade
the cell walls, thus inducing a thinning of the walls. But even in the late
stages of the wood decomposition, a stiff scaffold structure remains via which
the sound waves can still travel directly.” Even the modulus of elasticity is
not compromised; the wood remains just as resistant to strain as before the
fungal treatment – an important criterion for violin making. Before the wood is
further processed to a violin, it is treated with ethylene oxide gas. “No
fungus can survive that,” Professor Schwarze said.
That ensures that fungal growth in the wood of the violin is completely stopped.

Together
with the violin makers Martin Schleske and Michael Rhonheimer, Professor Schwarze
developed violins made of mycowood (wood treated with
wood decay fungi). In 2009 the violins were played in a blind,
behind-the-curtain test versus a genuine Stradivarius from 1711. All the
violins were played by the British violinist Matthew Trusler.
The result was surprising for all participants: Both the jury of experts and
the majority of the audience thought that the mycowood
violin that Schwarze had treated with fungi for nine
months was the actual Strad. “Of course, such a test
is always subjective,” Professor Schwarze said. “There
is no clear-cut, scientific method for measuring tonal quality.”

Currently Professor
Schwarze is working on an interdisciplinary project
to develop a quality-controlled treatment for violin wood, with successful,
reliable and reproducible results. Until 2014, within the scope of the project
that is funded by the Swiss Walter Fischli Foundation,
30 additional violins shall be made from fungally-treated
wood. Schwarze explained what opportunities this
project can lead to: “The successful implementation of biotechnological methods
for treating soundboard wood could in the future give young musicians the
opportunity to play on a violin with the sound quality of an expensive – and
for most musicians unaffordable – Stradivarius.”