Acoustic characterisation of “virtual” musical instruments: Using MLS technique on ancient violins

In this paper the realisation of “virtual” musical instruments, in which the instruments are treated as linear systems characterised by their impulse response, are analysed. The impulse response is treated as a numerical filter, which is convolved with the force excitation signal coming from the chords, producing a signal containing all the acoustic characteristics of the instruments, and avoiding all nonacoustic phenomena. The aim of this work is multiple: the “virtual” instruments can be used in subjective listening tests for the evaluation of the “sound quality” of different instruments, as reported in this paper. Other possible uses are for the (real or virtual) restoration of ancient instruments, and for preliminary listening tests on newly designed instruments. Various measurement techniques of the impulse response have been tested, employing different transducers and numerical analysis. For validating the accuracy of the new technique, a subjective listening test has been conducted. Some original music samples have been played by Maestro Marco Fornaciari, on three different violins and a viola in an anechoic chamber; both the acoustic-radiated signal and the excitation of the chords on the bridge have been digitally recorded. The results of the listening tests confirmed the excellent degree of similarity between the direct acoustic recording and the convolution technique. © 1998, Taylor & Francis Group, LLC.