How to repair a rubber speaker surround?

[vwdude]

I bought a pair of Dynaudio speakers and one of them has a small rip in the surround. They don't make replacement surrounds for these speakers so I need to repair it. What kind of glue or epoxy works best? It needs to be flexible enough to not hinder the movement but still needs to seal it up. I don't want to gum it up with silicone unless you guys have used it and can verify that it's the best solution.

[Bfowler]

id like to know this too! i have some polk coaxes and all of them have the surround coming off around the edges

[Eric D]

There are flexible glues which are just for this purpose. I have used them before, but regrettably I have no idea what they are exactly or who makes them.

Some digging on the web may help you find them.

[Weaklink]

Back in the day we used clear fingernail polish. Stays flexible and it's light. I'm sure there are better options nowadays.

[vwdude]

I searched eBay but I mostly found glues meant to be used when replacing the surround. What makes it tough is the rubber that Dynaudio uses is extremely thin, so it would end to be a superglue type of density, but needs to dry as be flexible.

Weaklink, that's an interesting idea. I'll keep it in mind if i don't get any other ideas.

[Virtue]

In the past I have used black silicone and I cut some heat shrink in half that matches the curvature of the surround. I then glued it on the back side of the original torn surround. So you can't really see it from the top, unless you look at it from the back side of the speaker. It works well and it moves quite well with the cone movement.

[vwdude]

That's a really good idea. Obviously I would a very small amount of black silicone. Thank you for that info.

[trickyricky]

Using a little on both sides?

I found out yesterday that my subwoofer cone's cracked (freaking tools).... its not that bad, about 3/4" long, shaped like an "L" . Am thinking about adding either some epoxy or silicon on the rear side of the cone. May be even a little dab of clear silicon one the front.... its impossible to tell if its leaking due to being in a ported box.

[wash with gasoline]

I have had luck in the past with black silicone (beater work trucks ect)
Smeared it on front and back of rip so the silicone can actually go threw the damage and glue it threw the middle also. Make it thin and spread it away from the damage a inch or so. Let it dry a few days before use. Had them last years this way.
Never tried it on anything nice though...

[ttocs]

are they that different that there isn't a replacement that is close enough to work? I would be more inclined to replace the surround with the closest similar piece I could find then to make a Band-Aid repair like this on a nice speaker...

[Eric D]

are they that different that there isn't a replacement that is close enough to work? I would be more inclined to replace the surround with the closest similar piece I could find then to make a Band-Aid repair like this on a nice speaker...

The surround is just one of the many elements which determine how a speaker will sound. Its weight, its flexibility, and its shape all contribute to the final sound of a speaker. Replacing it with a non OEM one would likely result in a totally different sound from the driver. Even a patch repair on it will affect it, but probably not nearly as much as a complete replacement of it.

[vwdude]

are they that different that there isn't a replacement that is close enough to work? I would be more inclined to replace the surround with the closest similar piece I could find then to make a Band-Aid repair like this on a nice speaker...

The surround is just one of the many elements which determine how a speaker will sound. Its weight, its flexibility, and its shape all contribute to the final sound of a speaker. Replacing it with a non OEM one would likely result in a totally different sound from the driver. Even a patch repair on it will affect it, but probably not nearly as much as a complete replacement of it.

This.

In all honesty, I looked for a close replacement but they don't offer it, and nobody makes one for this specific speaker. This is why I am looking for the best way to repair it. I could have just used a glob of silicone, but I wanted to learn about different techniques, which is what I am seeing, so thanks everyone for the input.

[Eric D]

Have you tried contacting Dynaudio about it?

I don't know if they would help or not, but let's face it, Dynaudio is a pretty high end audio manufacturer. I am confident they would be very helpful. They might either suggest a specific glue to use, give you the option to purchase a new surround, or quote you a repair price on the driver (which might not be all that bad, as soft parts are generally cheap, it is the hard parts which contribute most to the cost of a driver).

[ttocs]

I would replace both surrounds even if the other didn't need it to minimize differences in the two. I think just trying to put a band aid on it like that will only lead to a bigger failure around the surround where it was repaired. Is it an odd size/shape or something else that makes it hard to find something that would work?

[vwdude]

I agree, it think that Eric's last suggestion makes the most sense. It doesn't cost anything to inquire, but if I try to fix it and screw it up they might not be wiling to work with me then.

Worst case scenario I buy just one replacement woofer as one that I have is good still.

It all goes back to my original purpose for this thread, to see if there's a proper way to do the repair. I know how to repair electronics, this is something that I know very little about fixing though.

[Eric D]

You pretty much can't replace a whole surround at home anyway.

When building a speaker, a shim is placed between the pole of the motor and the voice coil. Once the spider and surround are glued, this shim is removed and then the dust cap goes on last. If you remove the whole surround, you would never be able to keep the coil centered when you try to glue a new one back on.

That being said, I don't know how Dynaudio builds their speakers in the first place. I am pretty sure the dust cap is molded to the cone in one piece. If the driver has dual spiders, with a spacing, they may glue them, and then remove the shim, then glue on the cone and make the final glue joint between the cone and coil in those slots you can see around the dust cap. I am just speculating though. If true, you might actually be able to replace a surround at home on this type of driver.

[quickrip]

I just repaired an alpine type r 15 with black weatherstripping glue from an auto parts store. worked very well. strong hold, made to take abuse, and flexible. Found this to be a better option than silicones which I've used in the past.

[vwdude]

I just repaired an alpine type r 15 with black weatherstripping glue from an auto parts store. worked very well. strong hold, made to take abuse, and flexible. Found this to be a better option than silicones which I've used in the past.

For a subwoofer surround I'm sure that works well but the surround for this 6.5" mid is very thin and I'm just worried about effecting the speaker response.

I think step one is to see if Dynaudio will/can repair it. I have read something from Dynaudio that their speakers are not repairable because every one of them is hand made and it's not possible to replace just the surround. I'll contact them and ask anyways.

[Eric D]

Any speaker can be repaired, it is just a matter of if it is cost effective or not. When repairing a speaker, all the soft parts are removed and replaced. This would be the cone, spider, surround, voice coil, dustcap, and wire leads. Back when I used to work for Rockford Fosgate, we would cut out repairs at a certain size (I think 8in). Anything smaller would just be replaced instead of being repaired. Often this means the customer got a new model speaker, which would then not match their other speakers...

[ttocs]

Any speaker can be repaired, it is just a matter of if it is cost effective or not. When repairing a speaker, all the soft parts are removed and replaced. This would be the cone, spider, surround, voice coil, dustcap, and wire leads. Back when I used to work for Rockford Fosgate, we would cut out repairs at a certain size (I think 8in). Anything smaller would just be replaced instead of being repaired. Often this means the customer got a new model speaker, which would then not match their other speakers...

I thought the same thing which is why I was confused 2 posts above when you said that a surround can't be replace?

[Eric D]

It is all or none, not just one part. The surround is glued to the cone, and removing it will damage the cone, plus result in a misaligned voice coil.

To repair (or rebuild depending how you look at it), you take a knife and cut around the surround, then reach down in and cut around the spider. The coil, cone, and spider now come out. You then grind off the remaining surround and glue, and spider and glue, down to a clean basket surface. We had a rotating jig for this grinding process at Rockford to make things faster.

Now you start over with the soft parts. First a spider with attached coil goes in place using a shim. Next the cone is glued onto the basket, (the cone comes with surround pre-glued). You then solder the lead wires, and glue the cone to the voice coil former. Lastly the dust cap goes on and the speaker is done.

I know some places sell replacement surrounds, but from experience I can tell you it is next to impossible to keep everything aligned when just replacing the surround.

[ttocs]

myself and my friends have replace I think 6 or 8 surrounds from everything from old advent 12" woofers to alpine mids and I can't say I have ever finished up and found they sounded worse then when I started. Sure in a perfect world do the spider and everything inside but in this case when its just repairing a ported surround I think it would be a bit of overkill to go through all that and still too nice of a speaker to put a dab of silicone on it and wait for its pending demise. Depending on the speaker you might damage the cone a bit but I can only think of one(the old advent) that once I got the surround started didn't just pull it off and leave the speaker intake. We would glue it to the speaker first and then with some careful measurements and a bean bag in the center of the cone to push it down to make contact with the basket to stick. I know its not perfect but I would do that over just trying to repair the surround myself. Between the movement of the surround and if its in any kind of enclosure building pressure the surround repair is just going to fail sooner then later where as if you did well on the surround you will probably not think about it ever again.