TG: cilindro sonoro(por)
TE: 100 tpi (cilindro sonoro)(por)
TE: 200 tpi (cilindro sonoro)(por)
UP (variação de): voltas por polegada(por)
UP (é traduzido por): threads-per-inch(eng)
UP (extenso de ): TPI(por)
UP (variação de): lines per inch(eng)
UP (variação de): grooves per inch(eng)
TE: 100 tpi (cilindro sonoro)(por)
TE: 200 tpi (cilindro sonoro)(por)
UP (variação de): voltas por polegada(por)
UP (é traduzido por): threads-per-inch(eng)
UP (extenso de ): TPI(por)
UP (variação de): lines per inch(eng)
UP (variação de): grooves per inch(eng)
Definição do conceito
[POR] sulcos por polegada : ...a gravação do sulco no cilindro, portanto, segue uma trajetória helicoidal em torno do raio R = (D/2) - ys. Aproximadamente 400 voltas de sulcos de som com passos
de 254 µm, eram cortados sobre a superfície do cilindro. Inicialmente eram 100 voltas por polegada, depois passou a ser 200 tpi (threads per inch). | FONTE: (SOUZA FILHO, 2018) https://www.scielo.br/j/rbef/a/dk3sdpSRQjxvJHVnWchFd7C/?format=pdf&lang=pt
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[ENG] In 1908, Edison introduced the wax Amberol cylinder, boasting double the number of grooves on an equivalently sized wax cylinder and hence a playing time twice as long as that of the Gold-Moulded cylinder. In the coming decade, the four-minute, 200 TPI (threads-per-inch) cylinder would replace the previous industry standard of two-minute, 100 TPI cylinders. | SOURCE: https://collection.sciencemuseumgroup.org.uk/objects/co117390/three-edison-amberol-four-minute-phonograph-cylinders-1908-1912-phonograph-cylinder
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[ENG] The earliest cylinders carried little or no identifying information, but later ones usually had the name of the selection, maybe the artist, and the catalogue number engraved in the thicker end, which could be squared off or beveled. The groove runs around the smooth outer surface like an extremely fine screw thread and plays from the end with the larger opening (never labeled) to that with the smaller one (likely labeled). Groove pitch is 100 threads per inch for a two-minute cylinder, 200 for the later four-minute type. | SOURCE: https://www.tnt-audio.com/vintage/edison_cylinders1_e.html
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[ENG] Blue Amberols have a maximum playing time of about 4 minutes and 45 seconds and play at the standard post-1902 cylinder speed of 160 rpm. Like the preceding black wax Amberols, they provide twice the playing time of 2-minute cylinders by using a finer groove with a pitch of 200 lines per inch instead of 100. | SOURCE: https://en.wikipedia.org/wiki/Blue_Amberol_Records
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[ENG] [The] ... "indestructible" style cylinders [Thomas B. Lambert - Lambert Company of Chicago] are one of the most durable forms of sound recording produced in the entire era of analog audio media; they can withstand a greater number of playbacks before wearing out than later media such as the vinyl record or audio tape. Their only serious shortcoming is that the celluloid slowly shrinks over the years, so that if it is on a core of plaster, metal or other very unyielding material, the ever-increasing tension can ultimately cause the celluloid to split lengthwise. A typical Lambert cylinder will have shrunk by approximately 3 mm in length in the 100 years or so since its manufacture. (The actual amount is very dependent on storage conditions.) Thus the grooves will no longer be 100 per inch, and the cylinder will skip if played on a typical feed-screw-type machine. The diameter will also have shrunk and many such cylinders will no longer fit on the mandrel unless very carefully reamed to fit. Such cylinders can still be played quite satisfactorily on suitable modern equipment. The Lambert company was put out of business in 1906 due to repeated actions from Edison for patent infringement, which Lambert had not actually committed. It was the cost of defending the actions that eventually sank Lambert. | SOURCE: https://en.wikipedia.org/wiki/Phonograph_cylinder
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