Tin foil to sheild speakers?

Discussion in 'Speakers' started by HienD, Jan 11, 2004.

  1. HienD

    HienD Stunt Coordinator

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    I just recently talk to the dealer that I bought a pair of Wharfedale from. He suggested attaching tin foil to sides of speaker help provide some shielding. Does this work? Going to have 2 sets of speakers in the front and one set has to be close to the tv? Going to be doing this with a set of bookshelfs.

    The guy is also the HT installer and owner of the store and seems very knowledgeable.


    Thanks
     
  2. Chu Gai

    Chu Gai Lead Actor

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    Not a chance in hell as that's not a property of Aluminum. Keep your speakers about 2 feet away from the TV and you'll be fine. If you can't do that, return the speakers and get shielded ones.
     
  3. Lee-c

    Lee-c Second Unit

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    If the t.v. has side-mounted speakers that may well provide enough shielding to keep the picture from being affected.
     
  4. Evan:R

    Evan:R Agent

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    While it may not shield your TV from magnetic interference, tinfoil is excellent when it comes to making hats to shield your brain from aliens. You never know when they could be monitoring you! [​IMG]
     
  5. GrahamT

    GrahamT Supporting Actor

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    Lee, the bucking magnets on the TV speakers will not have any effect on the magnetic lines of force from the main speakers.
    Aluminum foil conducts magnetic lines of force just as well as air or MDF speaker cabinets so they are no help either. You can add bucking magnets from www.partsexpress.com or as Chu said you can just move them out a bit.
     
  6. Lee-c

    Lee-c Second Unit

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    GrahamT: I wasn't referring to the magnets in the t.v. speakers, per se, just the various materials
    on the sides of the screen in general perhaps providing some protection. We had high quality speakers
    on stands directly next to our direct view t.v., a mere *5 inches* away from the t.v. on one side (the right side),
    and had no interference problems with the picture at all. So it's quite possible. But you won't know
    for sure until you try. [​IMG]
     
  7. Chu Gai

    Chu Gai Lead Actor

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    Just keep in mind that aliens are not looking to abduct you, they simply want to return you to your parents. Also, I recommend that you always make your own aluminum hats. Never buy a premade hat from someone you don't know, especially from websites. You run the risk of poorly made hats with pinholes that can allow mind control rays to enter. Also some people incorporate circuitry that actually enables aliens to track you and even act as transceivers. Electronic circuits are small you know. Further, the hats can be treated with psychoactive chemicals that will cause the fillings in your teeth to transmit and receive mind control signals. Always make your own, and remember, shiny side up [​IMG]
     
  8. Tyler M.

    Tyler M. Agent

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    Man, and all this time, I was wearing it dull side up[​IMG]
     
  9. Ray_C

    Ray_C Stunt Coordinator

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    Mee too! But when I put the shiny side out, my picture distorts. Can't have it all, I guess.
     
  10. Chris Tsutsui

    Chris Tsutsui Screenwriter

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    "Tin" is not ferromagnetic which means it won't do any shielding. Aluminum is also not a ferrogmagnetic which explains why magnets don't stick to my Aluminum foil helmet.

    You need to find rolls of iron, cobalt, or Nickel. [​IMG]

    Oh and If you use too thin of a sheet and it rusts, rust will make it weaker than it was as a pure metal.

    Also, if you think lining your cabinet with U.S. nickels is gonna help, it probably won't because nickels are like 75% copper so you'd have to use old fashion pure nickels.

    More science class info:

    The strongest available permanent magnets consist largely of neodymium, a rare earth metal with atomic number of 60 and symbol of Nd. Since Nd is a brittle, slightly toxic metal that easily corrodes in air, the commercial magnets often are coated with nickel, another familiar magnetic metal, which is less likely to chip or corrode.
    These magnets are actually made of an alloy of neodymium, iron, and boron. Alloys of different elements make stronger, longer-lasting magnets because pure magnetic materials usually demagnetize quickly. The reason is that the magnetic forces favor breaking up the into domains whose magnetizations point different ways and cancel out. When there are enough impurities in the material, the boundaries between the domains get stuck, keeping most of the domains from losing their alignment. That's why good permanent magnets are often made of alloys, like Alnico, in which one of the components (like aluminum) isn't even magnetic.
     
  11. Chu Gai

    Chu Gai Lead Actor

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    Alright, let's get back to classes [​IMG]


    While those are ferromagnetic, there's no guarantee they'll work. Although they may change the field distribution by bending the magnetic field away, they can also make matters worse by concentrating the field. It's very much a crap shoot and if you're hell bent on keeping the speakers, simply move them away.

    This brings up the issue of how do manufacturer shield their drivers. One way is strive for low external magnetic fields. Special magnet design, bucking magnets, and special cups that encase the magnet itself have been used sometimes individually, sometimes in concert. Now that doesn't mean that you should go out and buy an iron cup and place it over your driver's magnet. That'll do nothing more than screw up the magnetic field going to the coils.

    Also, while mumetal would work, that's prohibitively expensive and besides, bending it results in destroying part of its properties.
     

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