Qual é o primeiro trabalho com cancelamento de ruído?

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Título alternativo da pergunta: Stephen Bartholomew inventou o cancelamento de ruído?

eu acabei de ler "The Rumble and the Roar", de Stephen Bartholomew (Worlds of If Ficção científica, fevereiro 1957)

É uma história sobre altos níveis de ruído na sociedade moderna / futura e a invenção de uma máquina o cancela. O 1957 parece muito cedo para que essa tecnologia tenha existido na vida real. o Artigo da Wikipedia sobre o assunto não tem histórico.

Edite alguns dias depois Parece que eu estava enganado: o livro fala sobre 'Controle de ruído ativo', que não é sinônimo de 'Ruído branco'. A página da Wikipedia em Controle de ruído ativo mostra um histórico de patentes sendo concedidas para a idéia desde o 1936.

por James Jenkins 15.06.2019 / 13:26

2 respostas

Uma história anterior sobre cancelamento de ruído (não "ruído branco"):

1899: "O chifre de Marcus Brunder", um conto de Howard Reynolds na edição de junho do 1899 de O Gato Preto. De Everett F. Bleilerrevisão de Ficção científica: Os primeiros anos:

The story of Brunder, a strange little man who now wanders about the noisy sections of downtown Boston with a huge horn strapped to his back.

Backflash: The frame narrator, who maintains an office in an extraordinarily noisy port of the city, is often distressed by the racket outside. Brunder offers to cancel out the noise by inventing an apparatus that will nullify the vibrations by countervibrations. His experiments seem to advance, until in a disastrous moment he decides to test his progress at the Army proving grounds. The only result is that he loses his hearing. The invention seems as far away as ever.

16.06.2019 / 06:29

Aqui está uma história do 1950 sobre um dispositivo de cancelamento de ruído, como o da história que você vinculou na pergunta. Nada sobre ruído branco, no entanto.

1950: "Silêncio por favor!", uma breve história de Arthur C. Clarke na sua Contos do Cervo Branco Series; publicado pela primeira vez (como por Charles Willis) em Ciência-Fantasia, Inverno 1950, disponível no Internet Archive.


De Wikipedia resumo:

This comic story describes the efforts of a brilliant college student to design a machine that would produce a field of absolute silence. The gadget is then used in a prank, with tragic results. The story touches (albeit in a humorous way) on the popular science fiction theme of an inventor coming to grief at the hands of their invention that is best known from Mary Shelley's novel Frankenstein. The piece also references the composer "Edward England", an obvious parody of the work of Benjamin Britten.

The "Fenton Silencer" described in the story uses the same phase-inversion principle found in modern noise-canceling earphones.


Trechos da história:

"Suppose you have a train of waves — a peak here, a trough there, and so on. Then you take another train of waves and superimpose the two. What would you get?"

"Well, it depends on how you do it, I imagine."

"Precisely. Suppose you arranged it so that the trough of one wave coincided with the peak of the other, and so on all along the train."

"Then you'd get complete cancellation — nothing at all. Good heavens — !"

"Exactly. Now let's say we've got a source of sound. I put a microphone near it and feed the output to what we'll call an inverting amplifier. That drives a loudspeaker, and the whole thing is arranged so that the output is kept automatically at the same amplitude as the input, only out of phase with it. What's the net result?"

"It doesn't seem reasonable . . . but in theory it should give complete silence. There must be a catch somewhere."

"Where? It’s only the principle of negative feed-back, which has been used in radio for years to get rid of things you don't want."

[. . . .]

"I haven't made very extensive tests, but this unit can be adjusted to give almost complete silence over a radius of twenty feet. Outside that, sounds are deadened for another thirty feet, and further away everything is normal again. You could cover any area you liked simply by increasing the power. This unit has an output of about three watts of 'negative sound', and it couldn't handle very intense noises. But I think I could make a model to blank out the Albert Hall if I wanted to — though I might draw the line at Wembley Stadium."

15.06.2019 / 14:19