Principal Pitch in Vibrato Perception

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

Cancún

Congreso; 2nd Panamerican and Iberican Meeting of Acoustic; 2010

Acoustical Society of America

Vibrato is the more ubiquitous manifestation of a non-stationary tone that can evoke a single overall pitch, called principal pitch. Some recent results using non-symmetrical vibrato tones suggest that the perceived pitch could be governed by some stability-sensitive mechanism. A recently proposed one-parameter model based on time-frequency reassignment was able to predict previously reported results. The proposed model has some biological plausibility since the local computations at each auditory channel needed for pitch estimation are based on phase information, so they could be implemented in principle using the time interval between action potentials in the auditory nerve fibers. We studied the perception of principal pitch for asymmetric vibratos (trapezoidal) as a function of three different parameters: the duration of the stationary part (flat portion of the trapezoid), the overall depth and the starting phase of modulation. We compared the results with the predictions of the mentioned model and two previously formulated models.