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fundamentals although it does somewhat change the quality of the 

 tone.^ It it were not for this ability of the ear to add the fundamental 

 pitch of a note, of which only the harmonics are being reproduced, most 

 of the older phonographs and loud speakers would have been totally 

 useless for the reproduction of speech and music. 



Mechanical Versus Electrical Recording 



In attacking the recording part of the problem, two ways at once 

 present themselves; first, the direct use of the power of the sound be- 

 ing recorded to operate the recording instrument; and second, the use 

 of high quality electric apparatus with vacuum tube amplifiers in order 

 to give more freedom to the artists and better control to the process. 

 The amount of power available to operate the recorder directly from 

 the sound in the recording room is so small as to make it extremely 

 difificult to make records under natural conditions of speaking, singing. 



Fig. la — Picture of an orchestra recording by the acoustic process. This picture was 

 furnished through the courtesy of the Victor Talking Machine Company, Camden, 



New Jersey 



or instrumental playing. As the use of high quality electric apparatus 

 with associated amplifiers has a very distinct advantage over the 

 acoustic method, they have been adopted for the recording part of the 

 process. Fig. la shows a picture of a group of artists recording by 



^ Physical Criterion for Determining the Pitch of a Musical Tone, H. Fletcher 

 Phys. Rev., Vol. 23, No. 3, March, 1924. 



