THE GRAMOPHONE REDDIE. . %25 



It will be seen that the process of producing a commercial record 

 is a long and intricate one. It is, further, a process or series of 

 processes which have required a very high degree of scientific skill 

 and untiring experimental work to bring the sound record to its 

 present pitch of excellence. There are still objections to be over- 

 come, and perhaps the greatest of these is the hissing or scratching 

 sound produced by the needle in reproduction. There is, however, 

 no reason to doubt that eventually this will be overcome. A material 

 will be found for making the records which will insure that the sides 

 and bottom of the sound gi'oove are absolutely smooth. Even this, 

 however, will not entirely eliminate the scratch, which must be re- 

 garded to some extent as inherent in the sound groove. The recording 

 point makes a slight hissing noise as it cuts the wax, and that means 

 that the recording point is vibrating on its own account, apart from 

 the vibrations which it is conveying from the diaphragm to the wax 

 tablet ; consequently we must expect the recording point to be regis- 

 tering its own scratch vibrations as it goes along. These scratch 

 vibrations are exceedingly minute and of a very high frequency, and 

 in the ordinary course might not be heard were not the diaphragm 

 abnormally sensitive to vibrations of high frequency ; the actual result 

 is that the scratch waves are reproduced with proportionately more 

 precision, if anything, than the musical waves of the selection. 



An invention has recently been published which, if practicable, 

 should do much to remove the defect of scratch. According to this 

 invention the stylus of the recording sound box, instead of cutting 

 a groove in a wax blank, is made to deposit a fine stream of material 

 upon a polished surface. The original record, therefore, has a raised 

 sound line on it, instead of a grooved one. The substance deposited 

 is one which quickly hardens on deposit, so that it will not spread 

 on the polished surface. A negative is made from this original, and 

 the matrix used for pressing is made from this negative. 



Much attention has been bestowed on the diaphragm both of the 

 recording and of the reproducing sound box. Diaphragms have been 

 tried of almost every possible substance. Copper, tin, celluloid, 

 rubber, leather, gold-beater's skin, animal membrane, glass, and mica 

 have all been used, anfl as many different methods of supporting 

 them in the sound box have also been tried. The object aimed at is 

 to secure a light and highly sensitive diaphragm, and to hold it in the 

 sound box so that in vibrating under the impact of the sound waves 

 it will buckle as little as possible, for the effect of buckling is to 

 slightly distort the sound waves. A glass diaphragm is usually 

 employed in recording sound boxes, one being selected out of a score 

 that may be tried. Keproducing sound boxes are now always made 

 with mica diaphragms. 



