An Electronic Device for the Production and Measurement of Warble-Tones
John F. Corso · The American Journal of Psychology · 1955
quency of the tone of reference.' While several methods are available for modulating frequency, i.e. producing warble-tones, none is especially adapted for the problem at hand.2 Some methods employ fairly expensive beat-frequency oscillators; others fail to provide rates and extents of modulation which approach threshold values. Furthermore, techniques for the calibration of such auditory stimuli are not readily available. The present paper describes an inexpensive device for producing frequencymodulated tones and it outlines a specific procedure for calibrating the rates and the extents of modulation.