Could someone identify these?
We have four of these. They are about 10–15 pounds each and are highly magnetic. I dont have an exact value for lift strength, but its fairly strong.
http://tinypic.com/r/r1igl4/9
There are two to show top and bottom. I can add more pics if needed.
Observing members:
0
Composing members:
0
8 Answers
@reddeerguy1, thats what i thought originally, but was not sure. Typically those are not detachable
I agree that they look like speaker magnets. Do you have an idea how old they are? Because if they’re more than 30 years old, they could be somewhat valuable. Old speakers were often made with rare-earth magnets (which can be pried off from the rest of the speaker).
No clue at age. Ill look more into it
Not speaker magnets, no center pole for the voice coil. They appear to be the magnets from a resistance trainer of some sort, like an exercise bike. They are there to induce eddy currents in the flywheel which cause an opposing force to the direction of travel.
Speakers are usually made with C8 magnets (ceramic #8). Rare earths are seldom found in speakers outside of modern earbuds. Much older speakers will have weaker magnets that look like rare earth but will be alinco#3 or #5 and not really valuable.
@ARE_you_kidding_me The pole isn’t part of the magnet (at least not on older speakers). You’re right, though, they could be from an exercise bike or something like it.
@bestbroseph Could you put them next to something so we can see their relative size?
A better picture would help, side profile. Modern speakers have a ceramic 8 “ring” and the voice coil pole was part of a metal backplane that sandwiched the magnet. Not seeing it here. If we can see the side it will show the signature black ring magnet sandwiched between two metal plates. Relative size would help too.
I am leaning towards a speaker magnet as when I googled it I came up with this pic from a speaker geek forum.
It has the same stainless inner ring. What is throwing me though is the pic on the right has a keyed inner ring that suggests it once mated with something perhaps in a magnetic clutch type assembly perhaps in a piece of exercise equipment and the visible wear and tear would support this theory. But my searches never produced a like image other than the one above. The 10–15 lbs sounds lager but I have ancient Voice of the Theater speakers and the 15 inch woofers are every bit as heavy.
Answer this question 
This question is in the General Section. Responses must be helpful and on-topic.
Composing members:
0
