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Has this been done?

  1. Dec 24, 2004 #1
    I do not know what forum to post in, so I am posting here:

    Whether it be on a train, in a crouded room, or just during a storm, outside noises can make reading un-bearable. I know ear plugs could probably do the same thing, but I was thinking if it would be possible to take a cd player or mp3 player and play a track which has a frequency that basically plays "silence." The louder you make it, the less outside noise you hear. I would assume it would have to be at a very high frequency but I could be mistaken. It would be nice to simply put a cd into a cd player that blocks out all outher noises. So my question, has this been done before? Does anyone know a range of "safe" sound frequencies, because I would hate trying this out only to find myself going deaf. Also, do you think there is a practical use in this or should I just buy some ear plugs to block out sound..
  2. jcsd
  3. Dec 24, 2004 #2
    dude, please, please let me make you a machine that plays silence. it might be a little bit on the pricey side, silence is golden, but I will work out a payment plan for you.
  4. Dec 24, 2004 #3
    How loud do you want the silence? does anyone here know exactly how many decibels of silence starts to damage the inner ear?
    While I've got you here do you want this machine to do anything other than play silence? I was thinking of adding the Invisibility and Weightlessness options at no extra cost. well, no extra cost except for the added shipping and handling.

    "The king's not wearing any clothes."~little boy
  5. Dec 24, 2004 #4
    Hmm, almost like a machine that would make you go temporarily deaf. That would be quite an invention, I know I would definately buy one, if it was reasonsably priced of course. For now, however, I would just use earplugs.
  6. Dec 24, 2004 #5
    does $19.99 sound reasonably priced enough to you? I guarantee my machine will be completely silent, and I'll even waive the shipping and handling charge.
  7. Dec 24, 2004 #6

    Ivan Seeking

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    The closest that one can come to this in reality is sound cancellation technology. In principle it is possible to make a device that would detect sound approaching a point, and then produce an inverted wave that mostly cancels the noise over some region of space around that point. Unfortunately this is very difficult to do in practice. The best compromise is to use this technology in a set of headphones - now made by Boze.


    which I had on my kitchen table 20 years ago, way ahead of Bose. :cry: :cry: :cry:
    Last edited by a moderator: Apr 21, 2017
  8. Dec 24, 2004 #7
    my machine can be silent with or without headphones. If you get some really good, sound proof headphones you can REALLY hear the silence without all that distracting outside noise.
  9. Dec 24, 2004 #8
    I also have a prototype "dark sucker" if you would like to check it out. If it is really dark, just point the dark sucker at whatever you want to see and all the darkness is sucked away. It comes with 2 AAA darkness storage units, when these storage units begin to fill up you will notice a slight reduction in the amount of darkness being sucked. Simply replace the units with two new, empty ones and the dark sucker will be good as new.
    I think it is really neat to hold your hand in front of the dark sucker. An area of darkness will remain on a wall behind your hand where the darkness cannot be sucked. By arranging your fingers into different positions you can actually make pictures on the wall. My favorite is a bunny.
    Last edited: Dec 24, 2004
  10. Dec 24, 2004 #9


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    Do the dark suckers stop working sooner or later, at which point you can actually see all the dark inside them? I want one!
  11. Dec 26, 2004 #10


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    LOL! I think tribdog's answers about playing silence are the best. If you meant blocking out sounds and still listening to music, they make headphones like that...they're big and clunky though. I don't know if they block all the sound, but probably most, and then can be fitted with a radio receiver to play music (or, in the case of the ground crew at the airport, to use for communication...at least that's what I think they do with those big orange things on their ears). As for masking noise with noise, you can get a white noise machine, which sounds like you're listening to static. Unfortunately, in order to effectively block out surrounding sound, it is loud enough to damage hearing with prolonged exposure (they are truly obnoxious sounding, and I'd recommend wearing earplugs around them). I could give you the Tommy the Train "record" player I got my nephew...you can't hear anything else over Twinkle Twinkle Little Star being played by a whistle for hours on end, trust me, we tested this thoroughly today. I have to work on teaching my nephew how to turn on the sound in case his parents get the clever idea of turning that switch off. I've been showing him on/off switches on everything, and got plenty of extra batteries for him too! I think I'll get rechargeable batteries as part of his birthday present later in the year. :devil:
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