Garage sale drivers

diyAudio Member
Joined 2007
EDIT
I wish we could edit titles
That should read GARAGE sale, although garbage might also be appropriate sometimes

So today I went to a heavily advertised garage sale and bought some cheap woofers.
One of them is unfortunately open circuit but that is the risk you take when you forget your multimeter.
But I thought the 2 small woofers were worth $10- because somebody had hot glued a coli to the back of each and the coils are worth a couple of bucks each.
The generic 15" is about what I thought it would be, 30Hz Fs and a Qts of 1.1 but I can do something with it.
Seller also had some cheap Jaycar 8" woofers but only 3 of them and you need 4 of these for any decent OB design
Anybody recognise the small woofer?
Fs is 50Hz and Qts is about .8 Might be usable in a party box
Maybe I can learn how to replace voice coils using the cheap open circuit driver as a learning tool or just screw it to a sheet of ply and use it as a magnet vice
 

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Thanx to the moderator Allen. 👍
I'm waiting to remove the coil from the driver and then I'll play some music through them.
If they sound OK or better playing naked then I'll play with them some more.
Just from interest how much interaction would there be between the coil and the magnetic field of the driver? I can't believe that anybody would do such a thing, I've always understood such interaction was destructive interference at its worst
 
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I had that thought too. I'd remove it, however here are some reasons to worry less...

The speaker magnetic field is (should be) static, and not in flux. The inductor does not have a core which would otherwise saturate with enough static magnetism. The inductor is outside the primary circuit of the magnet core.

On the other hand, the fact that it's next to iron may change it's value.
 
Nothing wrong with the old Jaycar inductors, you just have to know what you are doing and if the DCR is too great you just buy something better.
All inductors are evil really but to get the parasitic resistance really low costs more than a Behringer active unit.
Also near enough is good enough sometimes, I wouldn't use a $100- inductor on a $30- woofer for instance
 
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Nothing wrong with the old Jaycar inductors, you just have to know what you are doing and if the DCR is too great you just buy something better.

I spent a few $'s on a couple of rebuilds by buying quality Inductors.
I'm realizing this might be OK if it's a personal project, but I need to keep in mind the speakers worth.

From posts like these I'm learning to keep an eye out for used parts, and clearances.