The vibrato on string instruments has been investigated as interaction between frequency modulation (FM) and amplitude modulation (AM). In order to evaluate the role of FM and AM, individually and as a whole in perceiving vibrato, three different kinds of vibrated sounds have been simulated through an additive synthesis: a FM-vibrato, characterized by a periodic frequency variation but without amplitude variations; an AM-vibrato, characterized by a periodic amplitude variation but without frequency variations; a FM-AM-vibrato, built using different phase displacements between FM and AM. The purpose of the present study is to investigate perceptual implications resulting by the simultaneous presence of FM and AM in a vibrated sound. Moreover, the correlation between the fluctuation of the spectral centroid and the perceived shift in pitch has been investigated in two cases: in sounds frequency-modulated using asymmetrical modulating signals, and in pure tones FM-AM modulated with variable phase displacements FM-AM. In all of these cases, the mean centroid moves to the same direction of the pitch shift. A “neutral centroid” sound, in which the spectral centroid is kept “neutral” and equal to the unmodulated sound’s one, has been generated in order to evaluate the relevance of energy distribution in perceiving vibrato tones.
The vibrato on string instruments: interaction between FM and AM
TRONCHIN, LAMBERTO;
2015
Abstract
The vibrato on string instruments has been investigated as interaction between frequency modulation (FM) and amplitude modulation (AM). In order to evaluate the role of FM and AM, individually and as a whole in perceiving vibrato, three different kinds of vibrated sounds have been simulated through an additive synthesis: a FM-vibrato, characterized by a periodic frequency variation but without amplitude variations; an AM-vibrato, characterized by a periodic amplitude variation but without frequency variations; a FM-AM-vibrato, built using different phase displacements between FM and AM. The purpose of the present study is to investigate perceptual implications resulting by the simultaneous presence of FM and AM in a vibrated sound. Moreover, the correlation between the fluctuation of the spectral centroid and the perceived shift in pitch has been investigated in two cases: in sounds frequency-modulated using asymmetrical modulating signals, and in pure tones FM-AM modulated with variable phase displacements FM-AM. In all of these cases, the mean centroid moves to the same direction of the pitch shift. A “neutral centroid” sound, in which the spectral centroid is kept “neutral” and equal to the unmodulated sound’s one, has been generated in order to evaluate the relevance of energy distribution in perceiving vibrato tones.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
