CHANGES IN PROGRAM BAND WIDTH 



speech. The data showed the frequency limitations as compared with un- 

 Umited bands (about 15 kc.) which yielded a vote of 60 to 40%, and 80 to 

 20% among a considerable number of observations. In Table I these data 

 have been interpolated to determine the limits that would correspond to a 

 xoie of 75 to 25%, in line with the criterion assumed in this paper. In 

 making the interpolation, it was assumed that the curve of per cent of ob- 

 servers voting correctly for the wider band versus logarithm of the frequency 

 is a straight line in the range of interest. 



Table II 



Musical Instruments 



1. Bass Viol 



2. Bass Tuba 



3. Timpani 



4. Bass Drum 



5. Bass Saxophone. . . 



6. Bassoon 



7. Bass Clarinet 



8. Cello 



9. Snare Drum 



10. Piano 



1 1 . Trombone 



12. French Horn 



13. Clarinet 



14. Trumpet 



15. Soprano Saxophone 



16. Violin 



17. Oboe 



18. Flute 



19. 14 in. Cymbals 



20. Piccolo 



Speech 



Male 



Female 



Sound Effects 



Footsteps 



Handclapping 



Key Jinghng 



Lower Frequency Limit 



Versus Unrestricted Band, 



Corresponding to One 



Liminal Unit 



53 cycles 



55 



60 



72 



72 



74 



80 



83 



87 



95 

 110 

 125 

 140 

 160 

 210 

 230 

 240 

 250 

 370 

 510 



115 

 190 



95 

 135 

 915 



It is difficult to interpret these data from individual instruments in terms 

 of results to be expected from whole orchestras and other music as usually 

 heard. However, comparing Table I with Fig. 4, it will be seen that the 

 frequency limit determined from the present tests as corresponding to one 

 liminal unit for music falls about one third the way down the list of instru- 

 ments in the table, and the Umit corresponding to two liminal units falls 

 about two thirds down the table, which seems reasonable. Also the fre- 

 quency limit found in the present tests to correspond to one liminal unit for 



