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BELL SYSTEM TECHNICAL JOURNAL 



ness level of the combined tone. Similar results were obtained with a 

 complex tone having ten components of equal loudness and a common 

 frequency difference of 100 cycles. The results are shown in Fig. 9. 

 It will be seen that although the points corresponding to the different 



90 



70 



10 20 30 40 50 60 70 80 



LOUDNESS LEVEL OF EACH COMPONENT-DB 



Fig. 8 — Loudness levels of complex tones having ten equally loud components 50 



cycles apart. 



frequency ranges lie approximately upon the same curve through the 

 middle range, there are consistent departures at both the high and 

 low intensities. If we choose the frequency of the components largely 

 in the middle range then this factor h will be dependent only upon A/ 

 and Lk. 



