Re: How to stop Speaker Foam Rot before it happens.

In article <leg315-8h1.ln1@xxxxxxxxxxxx>,
dplatt@xxxxxxxxxxxx (Dave Platt) wrote:

The most common problem with home stereo speakers is that they
deteriorate around the poly-foam suspension or surround. This usually
happens from 10 to 15 years. Some people call it Speaker Foam Rot and
is usually caused by aging of the surround, not by any abuse. When
this happens you can buy a kit to replace the surround but what can
you do when the foam is still good so this never happens?

I'm told that this can be stopped by applying something to the foam to
protect it, keep it soft and stop the cracking. Most people I talk to
say amor all will NOT work but for some reason cause it to rot faster.
Other people I spoke with said to use hair spray or even apply peanut
butter (I seen this on a website).

What is the best chemical substance that can be applied to the poly-
foam suspension or surround that will protect it and keep it from
rotting? I would like to know something that really works and will not
harm the foam.

I have read several suggestions. Haven't tried any of them myself.

The breakdown mechanism for the foam is usually said to be oxidation
damage due e.g. to ozone exposure. That, I believe, is the rationale
behind using products such as Armor-All. I haven't read reports that
Armor-All would actually damage the foam faster, but since Armor All
is reported to be incompatible with some materials (e.g. polycarbonate
plastic, per the "put Armor-All on your CDs for better sound" debacle
some years ago) it certainly makes sense to be cautious.

I've read a report that indicates that foam "rot" is often just that -
a biological rot due to a fungus of some sort which actually digests
the foam. This report suggested that the application of some sort of
anti-fungal compound to the foam could help extend its lifetime. The
report suggested using one of the over-the-counter antifungals sold as
an athlete's-foot remedy, but I don't remember the specific active
ingredient recommended. One of the products which consist of
tolnaftate in a talcum-powder base would probably be safe enough to
use, although I don't know if it'd be effective. Some of these
products used to use undecylanic acid (undecylanates were/are often
used as industrial antifungals) in an alcohol carrier, but these seem
to have gone out of favor in the market (possibly due to their odor).

Some people have tried to protect/stabilize the surface of the foam by
brushing on a thin layer of silicone sealant. This would probably
change the compliance of the surround to some extent - I don't know if
it would be enough to affect the driver's performance significantly.
If I were to try this I'd use only a non-acid-bearing "neutral cure"
silicone adhesive/sealant, such as those sold for electronics use or
those sold as "metal safe" (they're more expensive than the vinegar-
smelling acetic-acid-cure variety).

There are different kinds of foam and they'll fail for different
reasons. The cones eventually get soft spots and sound bad too.

I don't worry about it too much. Getting new speakers every decade is a
nice change. If you calculate the cost of speakers over 12 years, a
$2000 set is under $14 a month.

If your speakers are dying early from ozone, GET RID OF THE OZONE!
Ground-level ozone destroys everything - clothing, paper, appliances,
and life. It's not good to have it in your home.
.

Relevant Pages

  • Re: How to stop Speaker Foam Rot before it happens.
    ... I know of people who have tried all kinds of remedies against foam rot. ... is usually caused by aging of the surround, ... I've read a report that indicates that foam "rot" is often just that - ...
    (rec.audio.tech)
  • Re: How to stop Speaker Foam Rot before it happens.
    ... is usually caused by aging of the surround, ... you do when the foam is still good so this never happens? ... say amor all will NOT work but for some reason cause it to rot faster. ... I've read a report that indicates that foam "rot" is often just that - ...
    (rec.audio.tech)
  • Re: torn surround
    ... >> How can I determine if the drastic lack of bass is due to the missing ... > Without the surround foam suspension, the speaker can no longer compress ... The speaker needs to be sealed with the foam ...
    (rec.audio.tech)
  • Re: torn surround
    ... > How can I determine if the drastic lack of bass is due to the missing ... Without the surround foam suspension, the speaker can no longer compress the ...
    (rec.audio.tech)
  • Re: How to stop Speaker Foam Rot before it happens.
    ... deteriorate around the poly-foam suspension or surround. ... Some people call it Speaker Foam Rot and ... is usually caused by aging of the surround, ... you do when the foam is still good so this never happens? ...
    (rec.audio.tech)