this is the 1878 Edison demonstration phonograph. Edison's original patent described indenting a yielding surface for the hill and dale vertical recording, his patent did not however cover the removal of material. it was actually Alexander graham bell that made the first actual "cut" recording by taking this same machine and filling the grooves on the mandrel with wax. that machine became the gramophone and was the basis for the Columbia company which eventually became CBS.
the stylus is a blunt steel needle driven by a rubber disc attached directly to an isinglass diaphragm powered by sound waves through a horn, a complete acoustic process. i spent over 100 hours working on this machine to make it more efficient, this sounds nothing like a tin foil phonograph, this is recorded on 1 mil aluminum foil and is simply indented as you can see by the second video, this works well and is surprisingly loud considering it is an acoustic recording indented on aluminum foil. this can be played approximately ten times before it begins to show serious deterioration.
indenting on aluminum foil
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