The main quantities which influence the acoustic properties of violin wood are as follows:
- The speed of sound of the longitudinal waves (longitudinal and transverse to the grain orientation)
- The specific weight (density)
- The vibration damping (longitudinal and transverse to the grain orientation).
The MARTIN SCHLESKE MASTER STUDIO FOR VIOLINMAKING uses a specially developed test setup to measure these quantities without any contact with the instrument. We have observed a considerable range of quality variations in wood specimens despite a very homogeneous (external) appearance in some cases: For example, the speed of sound of the longitudinal waves along the grain in spruce range ranges between 4800 m/s and 6200 m/s. The density ranges between 320 kg/m^3 and 420 kg/m^3. The quotient of these two quantities serves as a measure of the quality which can provide useful information for subsequent thickness graduation of the violin top plate.