Politecnico di Milano: In Search Of The Perfect Sound: The Case Of The Stradivarius Violins

A multidisciplinary team coordinated by the CNR engaged seventy violin makers in a listening experiment to compare and evaluate the sound qualities of four violins: two modern, one factory and one Stradivarius. The results, published in The Journal of the Acoustical Society of America, suggest that what makes the Stradivarius the most pleasant sound is a particular balance in the properties of the violin’s timbre.

The experiment was conducted by Carlo Andrea Rozzi from the Cnr Nanoscience Institute, Alessandro Voltini from the ‘A. Stradivari’ International School of Violin Making in Cremona, Fabio Antonacci from the Politecnico di Milano, Massimo Nucci and Massimo Grassi from the University of Padua.

The researchers used a very simple sound stimulus, the musical scale, so that the judgements were guided only by the timbre of the violin and not by other factors such as ‘liking/disliking’ a particular piece of music. Based solely on five notes, the listeners showed a marked preference for one particular violin, the Stradivarius. The researchers then identified a kind of ‘signature’ that distinguishes the preferred violin sound from those considered less pleasant. Thanks to an in-depth analysis of the descriptions provided by the listeners and vibro-acoustic measurements made on the instruments, they were able to describe the preferred sound as one that has a particular balance of ‘openness’, ‘clarity’ and ‘nasality’.

Establishing which aspects of the sound contribute to making the timbre of an instrument pleasant is important for violin making, as it paves the way for the creation of instruments with desired timbral properties. The vibratory measurements made on these violins also have the purpose of building, in the future, a data repository that enables the relationship to be estimated between the way the instrument vibrates and the timbre,

explained Fabio Antonacci.

The experiment was conducted in the name of excellence: thanks to the support of the Municipality of Cremona, the researchers had access to violins from the Historical collection of the Cremona Violin Museum and the excellent acoustics of the Auditorium room for listening tests.