Symposium on Wire Transmission of Symphonic Music 

 and Its Reproduction in Auditory Perspective 



Basic Requirements* 



By HARVEY FLETCHER 



The fundamental requirements involved In a system capable of picking 

 up orchestral music, transmitting it a long distance, and reproducing it in a 

 large hall, are discussed in this paper. 



IN THIS electrical era one is not surprised to hear that orches- 

 tral music can be picked up in one city, transmitted a long 

 distance, and reproduced in another. Indeed, most people think 

 such things are commonplace. They are heard every night on the 

 radio. However, anyone who appreciates good music would not 

 admit that listening even to the best radio gives the emotional thrill 

 experienced in the concert hall. Nor is it evident that a listener in a 

 small room ever will be able to get the same effect as that experienced 

 in a large hall, although it must be admitted that such a question is 

 debatable. The proper answer will involve more than a consideration 

 of only the physical factors. 



This symposium describes principles and apparatus involved in the 

 reproduction of music in large halls, the reproduction being of a character 

 that may give even greater emotional thrills to music lovers than those 

 experienced from the original music. This statement is based upon 

 the testimony of those who have heard some of the few concerts 

 reproduced by the apparatus which will be described in the papers of 

 this symposium. 



It is well known that when an orchestra plays, vibrations which are 

 continually changing in form are produced in the air of the concert 

 hall where the orchestra is located. An ideal transmission and 

 reproducing system may be considered as one that produces a similar 

 set of vibrations in a distant concert hall in which is executed the same 

 time-sequence of changes that takes place in the original hall. Since 

 such changes are different at different positions in the hall, the use of 

 such an ideal system implies that at corresponding positions in the 



* First paper in the Symposium. Presented at Winter Convention of A. I. E. E., 

 New York City, Jan. 23-26, 1934. Published in Electrical Engineering, January, 

 1934. 



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