Violin

model: 'Cobbett, Dickson-Poynder' 1703 by Antonio Stradivari.

This instrument was made in collaboration with the Laboratory of Research of Violin's Museum of Cremona.

Luca Trapasso graduated in 2014 with a thesis on the studies carried out on this instrument.

The classification of the tonal quality of an instrument is one of the most difficult and pursued research challenges that lasts for years.This topic becomes even more interesting if it has as protagonist a so fascinating and so old instrument as the violin. It became famous thanks to the great Italian masters. The legend says that the celebrated sound produced by their violins is also determined by the recipe of their varnishes. Nowadays, the impact of the varnish on both the timbre quality and the acoustics of the violin remains almost unknown. Strings also provide a great contribute to the characterization of the violin tonal quality. For this reason, understanding how the strings affect the tonal qualities can help the musicians to research a characteristic sound. To this purposes, in this work we inspect how the violin responds to the changes performed on several manufacturing materials. In order to do this, we extract as much information as possible from the sound produced by the violin, correlating them with two manufacturing parameters. The first concerns the varnishing process and the second is represented by the physical properties of the strings and in particular by the tension. The previous studies on the effects of varnishing have provided just a few considerations. In this paper we propose an innovative solution. We analyze the tonal changes introduced firstly by the ground coat and secondly by the varnishing on a brand new violin. The analysis are performed using frequency responses integrated with audio cues. In the same way, the impact on the sound of different string sets is analyzed. Part of the results are compared with those found in the literature for validation purposes. In addition, we identify several effects on the quality timbre and the acoustics of the violin introduced by the ground coat and the varnish. These effects can be taken into account by violin makers during the making process of the violin. Finally, a correlation is determined between the timbral effects introduced by the strings and their tension value. These results can be used by musicians to facilitate the selection of suitable strings to customize their sound.

https://www.politesi.polimi.it/handle/10589/89882