In article , "N Cook" wrote:
N Cook wrote in message
...
Anyone come across the situation where presumably some crud that was
otherwise safe in the bottom of the voice coil slot is now shifted and
causing distortion.
Owner in the habit of transporting face down - to avoid anything falling
onto the front face.
Any opinions on transporting face-down or cures. ?
Try operating for a while horizontally perhaps but face up or face down.?

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



The problem is now more likely the owner having stored it in a damp garage
for a few years , unused.
There were numerous spiders webs and insect cocoons inside the amplifier and
spot rusting of the metalwork of this combo.
So probably insect cocoon or rust flake has got in the coil gap or even cone
distortion due to damp differentially affecting/distorting the cone.
Presumably "palpating" the cone in different clock positions to feel for
rubbing would be the best disgnostic.

If there is any paint inside there, it can peal and fall off into flakes. I
saw one gap all rusted once.

greg