Is it possible to shield unshielded speakers?


Hi,

I bought a pair of paradigm Monitor 7's unshielded from a friend (at the time, this wasn't an issue).
Now,I plan to upgrade my tv to a widescreen (16x9). Since my living room is a bit small, I would like to know if it's possible to shield my present speakers or do I have to get a new shielded pair?

Thanks for all your help in this matter.

Litsa123;-)
litsa123
If you have any doubts re. your tv susceptibility to magnets---Put the speaker right next to the tv. In a min. you'll know.Remove the seaker straight off. Turn the tv off. Wait a few min./turn back on; the tv will degauss itself.------Leaving a speaker there long enough creates perm. burn in--irreversible damage. This refers to all CRT sets--glass tube or rear projection crt's. A boombox or small speaker on top of a glass tube set will create the same hell.---if left there over a long period.
Epoxy bucking magnets to the back of the magnets of your speakers. You can buy the bucking magnets from parts express
and other places.
I had this very problem myself once.I mutilated a pair of old bookshelf speakers laying around and cut the magnets off of the drivers and used them as bucking magnets.You wont need to glue or anything,the magnets will hold together just fine.Just for the record,I am not familiar with your particular speakers as far as size of drivers but mine were 10in 3 ways that I was shielding and the 4-5in midrange didnt even need it just the 10in driver.I agree with the others,I wouldnt do anything untill you do have a problem,you will know if the drivers are messing with the picture or not.
Ozfly: I think the trick is to ground the aluminum/copper foil.
When a magnetic field passes thru copper, electrical current is produced.
Give the current somewhere to go (ground) and the field is no longer a problem.
Dweller is right -- to expand on that just a little, I've always noticed the distortion on the edges/corners of the picture. The color may be saturated or the picture distorted. Even small distance separations can make a big difference since the strength of the magnetism increases on a squared basis with distance.

BTW, I presented the aluminum foil idea as a hypothesis above. More knowledgeable members shot that one down, so I wouldn't encourage anyone to follow that route. To reassure yourself, just put some aluminum foil on the outside of the speaker box -- surface closest to the TV. If there is no change, you've only wasted a few seconds of your time.
Joshl: The speaker magnets won't damage your T.V.
The T.V. picture will be distorted if it's too close to a magnetic field.
Is that really all it takes? Boy, I guess I was worried about not-much. I can't afford to lose my expensive equipment, but if all I have to do is separate things by a foot (or 2, for good measure) then that will be excellent.
I'd just move the center channel a foot-or-so away from the TV. This should do it.
I have the same question that Litsa123 had last month, only modified a little.

I have an older non-shielded floor-standing single speaker that I picked up used. To me, it's a quality speaker (B+W DM640) and I wish to do an experiment and use it as a center channel, set just slightly off to the side of my TV, a new Sony Trinitron 32 Inch.

Things aren't set up yet, and I won't go with this plan if it will damage the new TV. Is there something I can wrap around the speaker that will sacrifice looks but protect my TV? The room is large and the L-R vintage speakers will be three or four feet away at least from the TV, and so I'm not going to worry about them as much (although I haven't researched how far away things have to be, according to whatever guidelines HT users have found).

There seemed to be disagreement in this thread as to whether wrapping aluminum foil or something around the speaker would help. Does anyone have any insight on that, or any other wrapping?

jl
Bucking magnets? That reminds me of a kid, with a speech impediment, who came to my door on halloween night. I said: "You're a little pirate aren't you"? He said: "Yeth thir" and I said: "Where are your buccaneers"? He replied: "Under my buckin' hat".
It will probably be the Sony 42" LCD projection tv (kf-42we610).

Thanks alot for all your help.

Litsa ;-)
Simple fix for your situation. Buy what's commonly called "bucking magnets" and you superglue them to the back of the drivers magnet, tweeters too. You glue the "bucking magnet" on in the reverse polarity position, thereby canceling out the magnetic field.
Since you're planning to upgrade your TV to a widescreen and you stated that your room is small, why not get a plasma, which is widescreen. It solves your small room issue and magnetic shield problem. In addition, it would be a WOW factor and pics would look great. Ready to refinance? :> )
Aluminum and copper will not do the job for magnetic interference. You need iron or mu-metal. The former is heavy and hard to work with. The latter is expensive.
I'd wait until I was sure there is a problem.
If the speakers are screwing with your picture, then follow Ozfly's advice and see if you can replace the drivers with shielded ones.
Lastly, you can buy some sheet copper and try to fashion the shield yourself.
Yes, it would look kind of funny.
I wouldn't take this approach.
Good luck!
Is the new tv gonna be a tube or projection? If you are going with a projection, you won't have any problems.
Normally, you can unscrew the speakers from the front of the cabinet. I have not tried this, but I wonder if you can reach in and arrange some heavy duty aluminum foil on the side of the cabinet facing the tv. It would probably help if the foil could be sandwiched between the insulation inside the cabinet -- otherwise you might get some noticeable resonanance. This would be a cheap and easy experiment. Another plan of action would be to contact Paradigm to see if they have an aftermarket shield that can be applied to the speakers once you remove them from the box (there are normally four or more screws holding in the speakers -- you probably don't have to worry about the tweeter since that magnet is so small). I've found the customer service at Paradigm to be exceptional. Good luck.
I guess I can do that... But, would the shielding on the outside of the speakers be terrible looking of huge & will that do the job?

Litsa ;-)
You COULD shield them but the shielding would (probably) have to applied to the outside of the cabinet.

Why not use your current speaks for surrounds or a bedroom system and get new shielded ones?