Several years ago I had the good fortune of meeting Martin Schleske during one of my frequent trips to Munich Germany.
Joseph Curtain called Martin "one of the most important living violin makers" in a May 2001 article in The STRAD
magazine. And for good reason....
Martin is a gifted violin maker and scientist who is at the same time a student of the old masters, and a teacher. He has
devoted enormous amounts of time and energy to studying the smallest details of Stradivari, del Gesu, Montagnana and
others using analytical equipment and techniques normally only available to the scientific community, to help explain the
acoustic behavior of the violin. He has documented his work and findings in numerous journals and published papers, has
appeared on national television in Europe, and is a frequent guest speaker at events such as the annual meeting of the VSA
and Oberlin Acoustics Workshop.
The fist time I visited Martin's studio just outside of Munich, he was a very gracious and welcoming host. Having read many
of his publications beforehand, I was prepared with a battery of questions. Even with my technical background, much of the
material was difficult to understand without seeing it first hand, and Martin was eager to explain and to teach. It became
apparent after this and subsequent meetings, that while much of what Martin does is simply beyond the scope of
practicality for the average violin maker, some of the techniques and tools he was using could be distilled into "user-friendly"
tools that could be used by those interested in pursuing and applying improved acoustic knowledge. My goal is to apply
from his vast knowledge those techniques that could have significant benefit for the violin maker, and to develop practical
tools based upon them.
Varnish Analysis
In his paper "Towards a more musical violin varnish" Martin explains that the application of varnish can enhance or ruin the
sound of an otherwise well-built instrument. He states that good varnish should decrease damping of the wood and provide
an increase in the ratio of the speed of sound to the density. To assess the effects of the varnish he suggests preparing
spruce test strips, one for each step of the varnishing process so that the effects can be related to each step. A tiny rare-
earth magnet is then affixed to the end of the strip, and while it is suspended at it's nodal lines, a magnetic coil in close
proximity to the magnet is swept with a signal generator to determine the resonance peak of the sample. Using a dB meter,
the Q of the sample can be measured, and the speed of sound transmission can be calculated.
These photos are of the system I built, using a PC as the basic platform for the tool. The test stand supports a low-cost flat-
response reference mic that I elected to use rather than a dB meter for it's flexibility for use with other tools. The test
sample supports are fully adjustable to accommodate different length samples. On the left side of the stand is a brass
encased, custom-wound coil that was designed and made in my shop. It too can be used for other test tools. I have
experimented with numerous software packages, and have found SpectraPlus to be the best for my purposes, in spite of it's
relatively high cost.
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