Violin octet scaling revisited

• Published in: The Journal of the Acoustical Society of America 2006-05, Vol.119 (5_Supplement), p.3258-3258
• Main Author: Bissinger, George
• Format: Article
• Language: English
• ISSN: 0001-4966; 1520-8524
• DOI: 10.1121/1.4786088

Schelleng employed only two major resonances to scale the violin to other pitch regions, creating the violin octet: the main air (now labeled A0) to be placed at 1.5x and the main wood (B1, actually two modes) to be placed at 2.25x, the lowest string frequency. B1 employed flat-plate scaling and an empirical relationship between plate mode frequencies and B1. Experimental modal analysis of a complete octet showed flat-plate scaling for the corpus generally worked well, but A0 scaling was unreliable, even with postassembly modifications. Failure of the rigid-cavity Rayleigh relationship for A0 originated from an obvious major omission, cavity wall compliance, and one unobvious source, A0 coupling with the next higher cavity mode A1, which emerged much later via Shaw’s network model. Incorporating wall compliance into Shaw’s model greatly improved A0 and A1 predictions to within 10% over the octet. Acoustical analysis combined with patch near-field acoustical holography showed that A1, via induced corpus motion, was the most important radiator for the largest instrument in the main wood region and that the B1 modes, via net volume changes, can radiate significantly through the f-holes, two radiation mechanisms never considered in Schelleng’s original scaling.