414 



3 1 



I - 



100 



BELL SYSTEM TECHNICAL JOURNAL 

 VOWEL "er" 



HENRICi ANALYSIS 



i I ' I — r 



200 300 400 500 



I , , i ,i, iiH i. .F.ii ii.iii i ii , . 



1000 2000 



FREQUENCY IN CYCLES PER SECOND 



VOWEL **0U" 



3000 4000 



OPTICAL ANALYSIS 



I I i 



il 



kill 



■ ■■■'lili.l 



2 3 

 < 



> 



^ 2 



HENRICI ANALYSIS 



T«^ 



4 



u 



70 100 200 300 400 500 1000 



FREQUENCY IN CYCLES PER SECOND 



Fig. 5 — Analyses of spoken vowel sounds. 



liiiiil 



2000 3000 



