Perceived principal pitch of FM-AM tones when the phase difference between frequency modulation and amplitude modulation is in-phase and anti-phase.

Abstract

“Principapl itch” is defined as somewhast teadyp itch perceivedfr om periodically frequencym odulatedto nes, l ikev ibratot ones. Principapl itch of vibratot onesw hose frequencyal onem odulatedp eriodicalliys indicatedto be locateda roundt heir carrier frequencie (st hem iddleo f the extento f FM). Wes tudiedw heret he principal pitch of FM-AM to nesi s locatedb y the psychoacousticeaxlp erimenuts inga methodo f adjustment. FM-AM tones is defineda s vibratot one whosef requencyan d amplitude are periodicallmy odulated by an identicalm odulationw aveformsi multaneously. The principapl itch of FM-AM tones is shiftedh ighert han their carrierf requenciews hen the phased ifferencbee tween FM and AM is in-phase, and lowerw heni t is anti-phase. The shiftedi ntervalf romt he carrierf requenctyo the localizedp rincipal pitch of FM-AM tonei is proportionatlo the extent of FM and the square of the degree of AM. To interpreth esee xperimentrael sults, we suppose the psychoacousticmalo delw hich is the expansion of the pitch averaginmg echanismto perceivep rincipapl itch of FM tones. In this modelc, ontinuousclyh anginpgi tch of FM-AM to nesi s sampledw, eighted with its amplitudfel uctuationr, e gisteredin sensorys tore, and averagede veryc ertain moment. Thew eightinpgr ocessin this modeli s constructewd ithl oudnesps erception mechanism and the mechanismto perceivfel uctuatiosnt rength.We also discussed how the effect of intensity on pitch influences our experimentrael sults.