Precision measurement of violin string modes
Bernard Ricca, Gabriel Weinreich, Nicholas R. Michael · The Journal of the Acoustical Society of America · 1989
Following a suggestion of Benade (private communication) that small inharmonicities in the mode frequencies of a string may have important effects on its bowing response, a method has been developed for precisely measuring the (complex) normal frequencies and polarizations of a string as mounted on a violin, with the aim of determining, among other things, whether the violin maker's adjustments of bridge and soundpost are systematically reflected in the string's inharmonicity. The procedure, which uses acoustic excitation and a two-dimensional photoelectric detector of string motion, is based on earlier work [E. B. Arnold and G. Weinreich, J. Acoust. Soc. Am. 72, 1739 (1982)] but uses a higher frequency resolution (0.125 Hz) and a least-squares fitting of the resonant string response. Some results on the shift of string frequencies due to controlled loading of the bridge will be presented. [Work supported by NSF.]