Stray magnetic field effect on crossovers

[cotdt]

Anyone have any info on how far away the crossovers should be from the woofers? I just realized that when I added a buckin magnet to my Peerless HDS Exclusives the crossover point changed.

From my calculations the crossovers should be at least 2 feet away from the woofer and tweeter, unless they have a buckin magnet. Anyone can verify?

Edit: Spelling corrected

[David_D]

I am sorry that I cannot answer your question.


Edit: Thank You

[ThomasW]

Under normal circumstances a bucking magnet will not significantly alter the crossover frequency, nor will it have any more impact on the wiring than the stock magnets on the drivers.

Bucking magnets will to some degree minimally effect a few of the woofer's T/S parameters other than that their use is pretty benign.

[JonP]

Hmmm... interesting.

Just how close is the crossover to the magnet/driver?

I agree with Thomas, that there shouldn't be any special effect because it's a magnet. Just the normal "hunk of ferrous metal near an inductor and causing iron core effects" on an air core inductor. I did some tests once with a woofer, hunks of iron, isolated magnets, and our highly accurate LCR meter at work... and you needed to have things closer than 1.5-2", or the effect was insignificant.

Hmm... that was with air cores. There might be a bigger effect on an iron or powder core inductor, not sure now. They may be affected a bit farther out, but it really should be measured to see if that's so.

I'd be highly surprised that 2', or even 6" away would have a major effect, though.

[mmoeller]

The magnetic field in a conductor due to AC current flow decreases quickly with distance. I can't recall the exact scaling factor. I believe it decreases from at a rate similar to 1/2(radius). You can learn all you wanted to know about magnetism at the following.

http://www.ndt-ed.org/EducationResources/CommunityCollege/MagParticle/Physics/Magnetism.htm

There is an interesting page on fields in a coil, where the fields are concentrated in the middle of the coil. This makes these fields even less susceptable to effects from outside sources. It also tells you that your inductor placement and orientation is important, especially in regards to other inductors, but we all know that...

[Curt C]

Anyone have any info on how far away the crossovers should be from the woofers? I just realized that when I added a buckin magnet to my Peerless HDS Exclusives the crossover point changed.

From my calculations the crossovers should be at least 2 feet away from the woofer and tweeter, unless they have a buckin magnet. Anyone can verify?

Edit: Spelling corrected

Any effects will diminish at the inverse square of the distance. I can't imagine any audible effects if the crossover is 6" away or better. Cored inductors would be the most susceptible due to the permeability of said core. Perhaps you could orientate the crossover to maximize their distance.

C