Page 1 of 1

Looking for clarification

Posted: Thu Jul 24, 2008 9:37 pm
by BigDaddy
I'm pretty sure I know the answer but I'm just looking for a second opinion.

When you press down on the cone of a speaker, if it's scratchy that indicates a problem with the voice coil. What if the cone will not move at all? Does this mean the speaker is blown? Is it possible that after sitting for awhile the voice coil will become seized? If that is possible then is there any way to fix it???

Thanks for any help.

Jason

Posted: Thu Jul 24, 2008 10:04 pm
by Jacampb2
Yeah, if it feels rough, the VC former is likely deformed. It either over excursed and got beat up, or it over heated and deformed. If it is froze solid, then it could be the same as above, but it kept playing long enough to gall itself into one place, or something that happened to me once, the epoxy broke on the two magnets in the stack for the motor, one shifted just a few millimeters and the sub was frozen solid. This was on a JL12W6 that was shipped to me supposedly working. When it got here it was shot. I am guessing it took quite a jolt in shipping.

They can be repaired, but it typically means cutting the suspension and then when complete, having to glue the spider(s) and put a new surround in. Most time you have to re-wind the VC on a new former. It is way more trouble than it's really worth IMO. The end product will never be what it was.

Later,
Jason

Posted: Fri Jul 25, 2008 6:05 am
by Francious70
It's possible you're not pushing down straight which will make the VC scratch.

But if it doesn't move at all, then you've probably got a bad speaker. Test it with an amp at low power.

Posted: Fri Jul 25, 2008 4:46 pm
by BigDaddy
Thanks guys. This particular speaker doesn't scratch...it just doesn't move at all. I'll try hooking it up to an amp...hopefully tomorrow. Just didn't want to cause more damage by hooking it up to the amp.

Jason

Posted: Fri Jul 25, 2008 5:06 pm
by VW337
bust out a 9V battery and a chunk of speaker wire, tap the wire to the battery, good/functional speaker should jump, seized will not move.

keeping it ghetto.

Posted: Fri Jul 25, 2008 5:10 pm
by fuzzysnuggleduck
If it's already cooked now, the potential of further damage really matter... however, I'd be very careful with your amp on a seized VC.

Posted: Fri Jul 25, 2008 5:19 pm
by VW337
fuzzysnuggleduck wrote:If it's already cooked now, the potential of further damage really matter... however, I'd be very careful with your amp on a seized VC.
this is why I suggest a 9V battery, the battery will not harm a good speaker but I suggest only briefly tapping the terminals for test purpose only.

Posted: Sun Jul 27, 2008 10:54 am
by smgreen20
Jacampb2 wrote: something that happened to me once, the epoxy broke on the two magnets in the stack for the motor, one shifted just a few millimeters and the sub was frozen solid.
I had that happen to me on a Kicker mid. It was pinching the VC in place.