When it comes to choosing an ideal piece of wood for making a fine violin, a skilled craftsman can do as well as a supercomputer, researchers have found.
That is because traditional methods of testing wood's elasticity provide a surprisingly good estimate of the physical elements that determine most of the wood's sound properties, said Robert Schumacher, a physicist at Pittsburgh's Carnegie Mellon University who tried to improve on the old ways with a supercomputer.
When a violinist bows a string, the vibration is transmitted through the bridge to the instrument's wooden top plate, setting it to vibrating and adding greatly to the string's sound. The plate's vibrating characteristics are determined by the wood's "elastic compliance." For example, Norway spruce, the preferred wood for violins, is 20 times more compliant when it is bent with the grain rather than against it. A full mathematical description of these properties in the complexly curved top plate -- needed for computer analysis -- requires eight more such measurements.
Schumacher used a CRAY supercomputer to model the violin top plate, and found that only three are really necessary. For centuries violin makers have assessed all three by bending the wood along the long axis, along the short axis, then trying to twist it around the long axis.
Schumacher's findings were announced by the National Science Foundation, which supported his work. He said, however, that NSF cut off his funding some time ago.