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Speakers that are not magnetically shielded

  1. Feb 25, 2006 #1
    I bought new speakers, it came with a subwoofer which is not magnetically shielded. In the manual it says keep it at least two feet away from PC monitors, hard drives etc... Does this only apply only when the speakers are on? What's the worst that could happen if I don't follow this?
  2. jcsd
  3. Feb 25, 2006 #2
    try it and find out. and no it doesn't mean just when it is on remember that your hard drive is made of magnetic disks, and that a subwoofer has a huge magnet inside it.
  4. Feb 25, 2006 #3
    It will only distort display right? Then why did it say not place close to hard drives? Will it damage them?
  5. Feb 25, 2006 #4


    Most speakers have neodymium magnets these days, get a high enough grade one within a foot or so of a hard drive and it can corrupt the data.
  6. Feb 25, 2006 #5


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    The distortion can be pretty bad. I had to keep a TV close to some speakers that were marginally shielded. The TV developed rainbows on both sides near the speakers. I tried degaussing by hand, but it was permanent. The TV wasn't useless but it was very difficult to watch.
  7. Feb 26, 2006 #6


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    The magnetic field interacts with the lanthanide metals (usually Eu and Y in color TV) in the display screen and it will change the color. I believe it is the red phosphor that is affected, based on experience with my son.

    My son magnetized our TV several times until we figured out that he was doing it. The TV lost the red and we saw primarily green, blue and purple hues. We just degaussed the screen.

    A strong magnetic field will damage a harddrive in the sense that it will corrupt the data by changing the magnetic domains on the HD.
  8. Feb 26, 2006 #7
    I use an older home hi-fi amp and bookshelf speakers that sit about a foot away from the computer case without any problems
  9. Feb 26, 2006 #8
  10. Feb 26, 2006 #9


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    Possibly. One way to check is to hold a piece of steel or other magnet (or even a compass) on a string and gradually move it toward the magnet and not the deflection. Then cover the magnet with a tin can, and repeat moving the piece of steel or magnet on a string toward the covered magnet. If the deflection is less, then yes, putting a tin can over the magnet works. One should test in the direction of the object (TV or PC) which would be affected.
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