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This study examined the pitch characteristics of range and contour in pleasurable vocalizations produced by 12 infants at monthly intervals from 3 to 9 months of age. Computer analysis of the vocalizations identified a high percentage of descending contours (82%); mean frequencies for all subjects ranged from 313 Hz to 599 Hz, with actual frequencies ranging from 195 Hz to 1036 Hz. Vocalization characteristics compared by gender showed no difference between boys and girls during this period of infant vocal development. The data demonstrate the capacity of the infant voice to produce a wide range of pitches. Despite individual differences, the overall range is stable and closely related to those pitch ranges reported for older children.