Violin sound quality: nasality and clarityClaudia Fritz
This study aims at investigating what nasality and clarity means for violinists, and what their acoustical correlates are. Based on his measurement of the acoustical properties of a large range of violins, Dünnwald (1991) associated a large amplitude in the band 650-1300 Hz with nasality and a low amplitude in the band 4200-6400 Hz with clarity, but without any perceptual testing. Therefore, Fritz et al. (2009) conducted listening tests with English speaking violinists to analyse the relationship of these verbal descriptors to specific acoustical features of computer-generated (virtual) violin sounds.
The listening test was redone with French speaking violinists. To go beyond the simple labelling, the participants were asked to give explicit descriptions of what clair and nasal means for them and the reasons of their choices.
The results are very similar to those obtained in English and conflict with Dünnwalds suggestions. Like for clear, the results for clair yielded a high degree of consistency between subjects and the term was associated with an increase of energy in the frequency range 1.6 kHz to 3.2 kHz. For nasal, subjects could be divided into two groups, each showing high consistency. An increase in the band 1.6 kHz to 3.2 kHz increased nasalité for the first group while decreasing it for the second one. Linguistics analyses were then conducted on the descriptions given by the participants and were put in correspondence with the results from the listening test. While acoustical parameters cannot discriminate the two meanings of clair (rich in high frequencies and precise/definite), the two groups for nasal were semantically identified as corresponding to two meanings of nasality (the vocal nasality referring to the quality of a twangy voice for one group, and the phonetical nasality and/or the fact that the sounds appear low-pass filtered for the other group).