Recordings of 100 male and 100 female young adults who were judged to have normal speech, voice, and hearing were analyzed for vocal fundamental frequency. A technique of determining modal fundamental frequency by systematic screening of the recorded samples through variable filters was employed. The mean of the vocal fundamental frequencies of males was found to be 116.65 hertz and the mean of the vocal fundamental frequencies of females was 217.00 Hz.
Fitch JL, Holbrook A. Modal Vocal Fundamental Frequency of Young Adults. Arch Otolaryngol. 1970;92(4):379–382. doi:10.1001/archotol.1970.04310040067012