Franc Zabkar wrote in message
...
On Tue, 27 Jan 2009 16:56:04 -0000, "N_Cook" put
finger to keyboard and composed:

There is no overheating , scoring or any damage to the coil or elesewhere
just these lines.

http://home.graffiti.net/diverse:gra...voice_coil.jpg

I've often encountered speakers which sound distorted but are still
functional. By moving the cone by hand, I can feel and hear the coil
scraping against something. Would this be caused by blistered
insulation as a consequence of overheating?

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.


Any bits of swarf or grit, causing lines in service, would be only
half the length of these lines. They extend the whole axial length of the
coil former, into the dome space.


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/