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~misfit~[_3_] ~misfit~[_3_] is offline
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Default Vintage speaker repair advice wanted...

Somewhere on teh intarwebs Peter Larsen wrote:
~misfit~ wrote:
..
It seems that these really well-built drivers were previously used in
other Wharfedale cabinets, also acoustic suspension, but fitted with
doped cloth surrounds - and that quite a few of these speakers are
still going strong. It's only the rubber-surround ones that have
failed....



Sorry about the lateness of my reply, I stopped checking here regularly.

This does not make sense, rubber and foam are different, rubber
surrounds as used by KEF and B&W last very well, I am listening to my
1976 KEF Codas right now.


I also have some early 70s Goodmans Mezzo SLs that have 'rubber' surrounds
that are still sounding better than most modern 2-way speakers under five
grand - and my Wharfedale Denton 2s are of a similar era and also have
'rubber', which is still supple (although the glue with which the surrounds
were attached to the cast ali baskets has let go).

You say that it doesn't make sense, and point out to me the obvious - that
rubber and foam are different. However, whether you think it makes sense or
not it's what's happened. From the only other reference I was able to find
on teh webz about the phenomena (also with Dovedale IIIs) it seems the
particular 'rubber' used (it was one of Wharfedale's first uses of 'rubber')
is prone to going hard if the drivers aren't used for a long period of time.

So, sorry that you don't comprehend it but, I'm afraid it's the truth.

So I'm trying to find out how to make my own doped cloth surrounds to
replace the (now cracked and broken) 0.5mm thick hardened 'rubber'.
I'm an invalid on welfare so I have time, just not much money. The
only instructions I've found on the web that come close are for
making 'siliconed' cloth surrounds. However apparently no glue will
stick them to paper cones other than silicone - which is a once-only
job as the only way to remove it from paper cones (if the desired
result isn't achieved first try) destroys the cones.


Give them aftermarket foam surrounds, they are easily available in a
size that is likely to fit.


Did you skim-read? (Ahh, your name suggests that English may not be your
first language - but you write well enough so you *should* be able to read
it too.) I know my post was long (and you snipped most of it) but that was
to try to stop generic "get new replacement surrounds" type answers. The
drivers are 12.5" and, despite me searching all and every supplier of
after-market surrounds - and emailing quite a few of the bigger ones with
the various dimensions needed - there is *nothing* avaible anywhere on the
planet that I can find that will fit.

Or neoprene rubber if available.


Yeah, that would be awesome! Where can I get it to fit?

Corrugated cloth surrounds last better than anything else, but it is
possible that whatever they were made with is forbidden now. Foam has
some nice acoustic properties in terms of attenuating reflections
from the membrane edge.


Yep, this ain't my first rodeo.

Loudspeaker membranes and surrounds must always be protected from
direct sunlight.


Thanks, another thing I learned eons ago.

Seriously, if you couldn't help after properly reading the post cough then
it might have been best to not reply yes? I know this group is almost dead
and a bit of traffic might keep it off life-support but really? It's not
just traffic that is important it's also the quality of the advice given.

Best,
--
/Shaun.

"Humans will have advanced a long, long, way when religious belief has a
cozy little classification in the DSM."
David Melville (in r.a.s.f1)
[Sent from my OrbitalT ocular implant interface.]