Bucking magnets for monitors

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I purchased a pair of Yorkville YSM1s which are not magnetically shielded. To fix that I also purchased to "sets" of shielding. Upon opening the box I found just two bucking magnets, so I started to dig deeper into the subject.
Yorkville website indicated that there should be a bucking magnet glued to each speaker, in other words two magnets per box. The retailer insisted that only one magnet per box needed to be attached to the woofer because tweeter did not create any significant magnetic field.
I checked both, the tweeter and the woofer and found that the bucking magnet's size matched the size of tweeter magnet, and looked too small for the woofer's magnets.
Someone at Yorkville, Canada, explained that this bucking magnet can be fixed to EITHER tweeter OR woofer. He even suggested that since the bucking magnet did not match the shape of woofer's magnet all too well, it could be broken into two halves and glued separately.
Naturally, the Yorkville's answer should be most reputable.
Still, does anyone have experience to tell, should I go for tweeter or woofer? Or both? (I can purchase another pair of magnets or maybe use magnets from some blown speakers).
What effect does this kind of shielding have on the speakers performance and efficiency?

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I purchased a pair of Yorkville YSM1s which are not magnetically shielded

Why not take everything back and get some sheilded monitors?

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Wouldn't do it because I like how they sound.
In fact I rate their sound higher than enything else I heard in the same and even higher price bracket.
I'd rather spend another $20 for magnets.

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Sorry to be flip before, just seems a little odd, in these days of computers and music, for monitors not to be shielded. I guess that is part of why the other monitors are more expensive. I can't imagine slapping a magnet on the back would not have an effect on the speaker, but that is merely an uneducated guess. Hopefully someone who is "in the know" about those things will come in here and enlighten us.

I don't think I'd be breaking any magnets if I were you. Just in case you get things all stuck on and yo do notice a difference in sound, you could still take the whole lot back.

Good luck,
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