PUBLIC ADDRESS SYSTEMS 



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address system installation will be of the highest order. Where the 

 acoustic conditions are unfavorable it is necessary to make tests with 

 various arrangements of the projectors, in order to determine the 



Fig. 16a. 



most satisfactory one. It has been found advisable to carry out the 

 entire program previous to the performance in order that the oper- 

 ating force may become familiar with the sequence. 



Conclusion 



The usefulness of such systems is very well illustrated by a few of 

 the results which have actually been obtained. Fig. 14 shows a 

 crowd of approximately 125,000 people, every one of whom was able 

 to hear clearly and distinctly all of the words spoken in President 

 Harding's inaugural address in March, 1921. This crowd was rela- 

 tively small, compared with the crowd which could be accommodated 

 by one of the larger type systems. Some insight into the number 

 of people which could be accommodated can be gained from the fact 

 that such a system will cover comfortably a complete circle whose 

 diameter is 2000 feet when the projector units are placed at the center. 



