HORN LOUD SPEAKER SYSTEMS 



165 



5 •• 



^.or 



3 4 5 6 789 



FREQUENCY 



3 4 5 6 7 89 



(0^ 



CYCLES 



3 4 5 67S9 



PER SECOND 



Fig. 8.14. The peak amplitude frequency characteristics of vibrating pistons of various 

 areas in square inches, coupled to the throat of a horn having an area of one square inch, 

 for one watt output. 



100 

 80 



= 10 

 8 



Z 4 



20 100 1000 10000 



FREQUENCY IN CYCLES PER SECOND 



Fig. 8.15. yi. Efficiency characteristic of a horn loud speaker employing the horn of Fig. 5.6D 

 with the dimensions multiplied by three and driven by 4 cones, 12 inches in diameter, with 

 5 gram copper voice coils operating in a field of 14,000 gausses. B. Efficiency character- 

 istic of a horn loud speaker employing the horn of Fig. 5.5D with the dimensions multiplied 

 by one-half and driven by a diaphragm and an aluminum voice coil having a mass ratio 

 of two to one operating in a field of 22,000 gausses. C. Same as B save that the horn 

 dimensions of Fig. 5.5P are multiplied by two. 



