Principal pitch in asymmetrical vibratos: a new experiment and revision of models

ETCHEMENDY, PABLO ESTEBAN; MESZ, BRUNO; EGUÍA, MANUEL CAMILO

Huerta Grande, Córdoba

Congreso; XXVI Congreso Anual de la SAN; 2011

Sociedad Argentina de Neurociencias

Vibrato is a performing technique widely used by singers in all cultures, consisting in a quasi-periodic frequency modulation. Despite multiple frequencies are present in a vibrato note, when listening to a singer it is possible to extract a single pitch, called principal pitch. This principal pitch is equal to the geometric mean of the instantaneous frequency (f0) if the frequency modulation profile is symmetric, but it is still a matter of debate what is the principal pitch when frequency profile is nonsymmetric. Although exists evidence pointing to a "stability-sensitive weighting" mechanism which gives less weight to segments of the sound where f0 is changing rapidly, it is not clear a) the criteria used to assign weights and b) the way in which this is implemented by the auditory system. We present i) results from experiments of pitch perception for asymmetric vibratos as a function of the rate of change of frequency and ii) a comparison between predictions of several pitch perception models for our data and data of previous works.