Hi All,
I noticed that in some branded speakers there is a "piggyback" magnat on the woofers (like in the attached photo) and I was wandering how this "piggyback" affects the woofer?
How it affect the woofer's T/S parameters? and is there any benefit in adding an extra magnet to a woofer which is part of a "branded" speaker?
Thanks
I noticed that in some branded speakers there is a "piggyback" magnat on the woofers (like in the attached photo) and I was wandering how this "piggyback" affects the woofer?
How it affect the woofer's T/S parameters? and is there any benefit in adding an extra magnet to a woofer which is part of a "branded" speaker?
Thanks
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There is no attached photo in your post.
I believe the purpose for extra magnet is to cancel out external magnetism to prevent affecting crt monitors and tvs. Not an issue these days.
I believe the purpose for extra magnet is to cancel out external magnetism to prevent affecting crt monitors and tvs. Not an issue these days.
photo added.
I know about the magnetism cancelation thing but I've read somewhere that it's can enhance the woofer's magnet magnetism (maybe when the "piggyback" pole attached to the same pole as the woofer's magnet?) or is it BS?
I know about the magnetism cancelation thing but I've read somewhere that it's can enhance the woofer's magnet magnetism (maybe when the "piggyback" pole attached to the same pole as the woofer's magnet?) or is it BS?
Yes, when you add one magnet to another, you increase magnets strength. But isn't piggyback magnet in the oposite polarity? Are you asking what happens if you flip it?
It's not very effective anyway, lacking one pole piece. I believe this application reduces stray fields a bit. Long time ago I saw measurements on such an assembly, comparing it with one without the extra magnet. I can't recall having seen much difference.
It would be more effective if you could put it inside the magnetic circuit.. not a small operation by any means. I've seen minor changes nonetheless from just placing other magnets near it.
Still though, what do you hope to gain from it?
Still though, what do you hope to gain from it?
Excellent.
Speakers with big motors have their uses but you don't need one to have good sound. In any case it's good to experiment with a low Qes driver. They have a subdued bass response without the added boost of an enclosure, which doesn't help much in a sealed box, but they have the strength to push against a small horn throat.
Speakers with big motors have their uses but you don't need one to have good sound. In any case it's good to experiment with a low Qes driver. They have a subdued bass response without the added boost of an enclosure, which doesn't help much in a sealed box, but they have the strength to push against a small horn throat.
Piggybacking an external magnet with the opposite polarity pushes original magnetic field "forward" , you get a higher flux density where it matters: at the voice coil gap.
Yes, it is noticeable.
Ferrite magnet designs are very inefficient, typically about 25% of ring "donut" reaches inside gap, a HUGE amount is wasted outside.
That´s why you can stick screwdrivers and even hammers outside, also inside across the gap, etc.
All of that is USELESS field.
Piggybacked magnet does not add its own field, just pushes the original one forward.
Yes, it is noticeable.
Ferrite magnet designs are very inefficient, typically about 25% of ring "donut" reaches inside gap, a HUGE amount is wasted outside.
That´s why you can stick screwdrivers and even hammers outside, also inside across the gap, etc.
All of that is USELESS field.
Piggybacked magnet does not add its own field, just pushes the original one forward.