Recent perceptual studies employing analysis of natural vowels and synthesized complex waves have suggested that spectral parameters other than fundamental frequency may be operative in pitch perception. The present study was designed to investigate the extent to which high-pitched male subjects and males with normal vocal pitch could be distinguished by characteristic resonant frequencies and amplitudes, as well as fundamental frequency. Pitch judgments scaled by the pair-comparison techniques were related to spectral parameters. Data were collected from 1500-msec midvocalic segments of /i/ vowels produced by 25 subjects. The data suggested that some form of physiologic changes are manifest for the two groups such that the characteristics of the acoustic resonators are different for males with abnormally high-pitched voices. These subjects utilized a resonating system wherein the second formant was approximately 200 cps higher than was apparent for persons of normal vocal pitch. No differences in formant amplitudes were found. Inconsistencies in the fundamental frequencies and listener pitch-judgment data demonstrated the need for expanded knowledge of the relation of listener perception of pitch to parameters of the acoustic signal.