1 1 1 1 1 1 1 I 1 1 











' 









1 1 1 1 1 1 1 1 1 1 

















vg. S. 106. 5 db above 1 microbar 

 at 1 meter (peak level) 



































































































- 



. 



























^ 



y 





























^ 



y- 



























^ 



























































































































■ 



• 

























































































































































Depth 



Figure 27. Plot of frequency vs. depth for pneumatic sound 

 source (1-inch OD sphere inflated with compressed air). 

 Wall thickness 0. 3125 inch. 



1 u 



1 II 















~ 





— Avg. Sl 107 db above 1 m 

 at 1 meter (peak leve 



, 



















































































































































































^ 



^ 



• 

























^ 



^ 



^ 































^ 



























" 





^ 





















s 



































g, 



















■- 

















u 



































fc 







































































































10 



































Depth in Feet 



Figure 28. Plot of frequency vs. depth for pneumatic sound 

 source (1. 375-inch OD sphere inflated with compressed air). 

 Wall thickness 0.25 inch. 



51 



