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BELL SYSTEM TECHNICAL JOURNAL 



plotted so that J^ 5 (/) df— 1 in each case. In Fig. 5 the individual 

 curves for each of the six speakers are shown on a small scale ; in Fig. 6 

 the composite curve for the men and the composite curve for the 

 women, drawn separately, and in Fig. 7 the composite curve for all 

 six speakers, giving the data of curves QA and 65 equal weight. 



Fig. 7 — Energy Distribution: Composite Curve for All Voices 



These curves are very similar to a curve obtained by Dr. Fletcher of 

 this laboratory, using block filters and based on the simple calling 

 sentence "Now we're off on one." A general consideration of this fact 

 and of the data shown leads us to believe that the differences between 

 curves of this sort, made by the method described are due rather 

 more to differences between the voices of the individual speakers 

 than to the particular piece of connected speech which is chosen, pro- 

 vided the speech is of reasonable length. The differences between 

 the different voices are so marked that we should expect them to remain 

 even though we used as test material a connected speech ten or fifty 

 times as long as the sentence used. 



The Energy Distribution in Speech 



An interesting comparison may be made between the curves shown 

 for the energy distribution of "continuous speech" and certain specu- 

 lative curves previously constructed to indicate the energy distribu- 



