Loudspeaker suspension problem

[Dickie]

Hi all.
I would appreciate any thoughts or comments you may have regarding this problem. I have been asked to repair my cousin's 25-year old loudspeakers that seem to be suffering from some form of suspension distortion. The suspension is a standard nitrile-rubber rolled surround that in general is still soft and pliable. But as you can see from the photo it is becoming distorted and pulling away from the flat edge of the frame underneath. I can't understand why it is doing this, unless there is some sort of "memory" stored up in the material that wants it to flatten out. Both speakers are afflicted similarly.
Needless to say replacement drivers are not available (Seas 21F-WBX), and I'm not sure if trying some replacement foam surrounds is a good idea. My only thought at the moment is to try and glue them back down using Copydex. There's nothing to lose after all.

[Edward Huggins]

Yes, you may have answered your own question....use Copydex or a PVA adhesive. Be patient, use a sable brush and any excess can be damp-wiped off. There's no reason why you should not get a near-perfect result.

[Boater Sam]

Rubber doesn't last for ever, its just aging and swelling a bit.

[mole42uk]

Glue them back down, and it might be a good idea to rotate the drivers 180 degrees. Gravity is a persistent problem.

[Dickie]

Thanks to all. Sounds like any repair is just going to put off the inevitable. But there's no harm in trying.

[Edward Huggins]

A sound repair should put off the rather expensive inevitable for several years. You will be surprised at the result and the £££s still in your pocket!

[Goldie99]

I suspect gluing them back is just delaying the inevitable. Seas list the originals as foam surrounds, not nitrile-rubber, so refoaming may actually not be such a bad idea.... if you can locate some good quality foams.

http://www.seas.no/images/stories/vi...wbx_and_dd.pdf

[Dickie]

Yes I saw the data sheet and assumed that the rubber surround was an "improvement". Perhaps the reverse is true. There are foam replacements available on Ebay but I was unsure if they would sound any different or that fitting them might be an issue. It might be worth buying some as a last resort anyway.

[paulsherwin]

It's unusual for synthetic rubber surrounds to fail like that - it usually happens with foam surrounds, which is why the repair kits are all foam. Have the speakers been subjected to unusual stresses at some stage, such as being placed in hot summer sunlight?

You could just replace the drivers, though this will change the sound unless you use OEM drivers. Replacing the surrounds is tricky, especially the first time you do it, though there are some Youtube videos to get you started.

[Dickie]

I am assured that the loudspeakers have lead a very sheltered life!

[leslie5555]

Replacing the surrounds is a bit tricky but as Paul says there are YouTube videos to show you how.
I did it last year with 4 speakers on my jukebox.
If you search nsm galaxy speakers you can see my thread with some before and after pics.
And the end result was great sounding speakers once again.

[Edward Huggins]

Foam surrounds can deteriorate far worse than rubber and often reported here.
Why not just go ahead and re-glue them for nothing and see how they sound?

[Dickie]

Yes, that's exactly what I plan to do.