Rubbing voice coil on new speaker?

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OK, so a little while back I got a new speaker (local brand) but didn't really get to use it. When I finally did I immediately noticed distortion on low level/volume. When I popped of the grill and pushed on the driver I could hear the voice coil rubbing. I pushed on the cone centre and off-center and could still hear the rubbing.

So my question, is this driver a dud and in need of replacement, or is this something a new speaker could possibly do?

Thank you!
 
Depending on what the make, model and build is it could be caused by;
Being dropped and the magnet has moved slightly.
The basket not aligned with the magnet.
The voice coil has been damp and warped
or it is a poor quality build.
If you ease the cone sideways whilst gently moving the coil, if you have a good spot, the magnet is misaligned. A thump on the magnet with a sturdy piece of wood, in the direction of the clear coil, may improve it. Or indeed make it worse. 50/50 chance but last resort!
 
OK, so a little while back I got a new speaker (local brand) but didn't really get to use it. When I finally did I immediately noticed distortion on low level/volume. When I popped of the grill and pushed on the driver I could hear the voice coil rubbing. I pushed on the cone centre and off-center and could still hear the rubbing.

So my question, is this driver a dud and in need of replacement, or is this something a new speaker could possibly do?

Thank you!
I assume you already mounted it? Possibly the surface was not totally flat and you are warping the basket. Undo the mounting screws and see if it clears up.

I did get a bad 18 incher back in '79 out of the box, so anything's possible.
If you mean you bought the box with driver mounted, it still could be a non flat mount surface. Oh, also I had a basement flood and a pair of 15's got wet halfway up the pole piece, rust was hitting the vc.

Other than that, I have toasted my share of coils back in the day when I was young and stupid...I'm much older now.:D
Jn
 
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Thank you all for responding! This prompted me to take a closer look myself: I've unmounted the driver (yes, it was factory mounted) and peeked here and there and I believe it is possible that I have found the problem: some of the glue they used to attach the cone to the spider leaked and made the cone stick to the spider and pulled it slightly sideways. I could not completely remove the glue, but forcing the cone away from the spider at that exact spot seems to help. So I guess poor manufacturing is quite possible. It is locally manufactured, a brand called Hybrid.
 
I manufacture my own speakers and know what happened: standard modern speaker voice coil glue is 2 part Epoxy, normal thickness between honey and jam ... at room temperature, which takes 4 to 8 hours to harden, speakers are put face up on shelves for that time.

To increase assembly speed, it´s common to put assembled speakers in a large rack oven, or pass it through a conveyor belt type along a heated tunnel, "8 hour" Industrial Epoxy cures in 30 minutes at 100C or 10 minutes at 120/130C , BUT at such temperatures it becomes way more fluid and "runs like water" .

Personally I always oven dry speakers "face down" which is safe, just by chance I am assembling a batch of 25 12" guitar speakers, go figure, and they are currently in the oven curing the magnet to frame assembly, small world .
But some people to save a couple minutes oven dry them "face up" and then it IS possible that some too liquid hot epoxy oozes into the voice coil gap, what happened to you.

Clearly a manufacturing defect, they should replace it with a good one, no questions asked, there is no way you caused this problem.

Does this mean Hybrid is a bad factory?
Far from it, this happens now and then.
If anything, blame quality control which did not catch it before packing.
 
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