On the Band Width of Vowel Formants
Bruce P. Bogert · The Journal of the Acoustical Society of America · 1953
Measurements were made on a sample of vowel utterances, by male talkers, of the band widths of the first three formants. It was found that the band width was essentially constant and independent of the particular vowel. The mean values for bars 1, 2, and 3 were 130, 100, and 185 cps. respectively. Ten percent of the 300 band widths measured were less than 90 cps and ten percent greater than 260 cps.