| 摘要 |
There is described a method for making a metal master for producing a gramophone record provided with writing in the center thereof, particularly inside a pressure press, and according to which the engraving of the sound-grooves is obtained from a mold element which is prepared by galvanically plating metal on a non-conductive support which has been engraved previously, in which means are provided to prepare an etching on the center part of the non-conductive support, on which support is then performed the galvanic metal plating to form the one mold element for producing one record side.
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