Dynaudio BM6a - replace ring or woofer ?

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Joined 2014
Hi all !

I just got a pair of Dynaudio BM6a monitors. The only problem is that one woofer has a 6mm-7mm crack/cut crossing the rubber ring. The rest of the membrane looks ok.

I spoke with a local speakers repairs tech who said he will be able to only replace the rubber ring, for the cost of about 80-100USD. I know you can get a new driver for as low as 150USD but I don't live in the USA so shipping and taxes will make this cost about 250USD eventually.

My question is - should the performance of the woofer degrade by some amount once this is done (considering it was getting a professional treatment) ? as I know the process includes cutting off the old ring and pasting a new one instead (more material is eventually put on the membrane...)

Would it be even better only to patch the crack from behind, leaving the original ring in its place ?

Or should I spend the 250 bucks on a new driver ?

Thanks for any advice !
 
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Hi,

The ring you are speaking of is known as the surround. The quoted price sounds high especially considering you want to do both at once to keep them the same. I can't see a reason why not to attempt a repair and one means I've heard is using a bit of facial tissue and rubber cement. You attempt it on the back side to avoid the unsightly patch. Others here might have others ideas but if not, I recommend you prep the surface using methyl hydrate to ensure as positive a bond as possible. Use multi wipes with it and a clean rag or cloth. Lay some cement down, add the tissue and a little more cement to coat the tissue. This may require using rubber cement solvent so it "paints on a little easier and smoother. As always, practice on something else to get your quantities right.
 
Disabled Account
Joined 2014
Don't try to repair the old surround ... will not last I think and will change the characteristics

By that do you mean I should replace the entire surround, and not try to "patch" repair it ? So basically once done correctly, replacing the entire surround should not affect the sound ? or will it ?

Thanks
 

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I think Cal has the right idea. The Dynaudios surrounds are made to not be replaced with off the shelf Surrounds made for 6" or 7" drivers. There is a place in Australia that has the right surrounds find them on ebay. But I would try to fix then first. Find the right surrounds order them but while waiting for them to come in try the fix. If your careful and patient you may be able to store the new surrounds for when the old ones really rot-out in the future.
 
Disabled Account
Joined 2014
Thanks,

Yeah maybe it's a good idea to give a small fix a try before replacing the entire surround...

What would be the best way to deal with that rubber surround ? I read that Loctite 30540 (black glue) is the one Dynaudio originally use for it ? Should I use that one ? and what would you paste to it - thin tissue or anything else ?

Thanks again !
 
Disabled Account
Joined 2014
Thanks guys !

I think I'd be better to replace the surrounding (as a permanent fix) rather then 'patching' the crack...

So should I not worry about the performance of the element once the surrounding replaced ?

As seen on the pictures the surrounding looks too old - also on the other monitor. Do you think it would be a good idea to replace them both on once ? I mean would the sound and performance remain unchanged one replacing them two, if done by a professional ?

Thanks again for your advice !
 
Hmmmm, by the look of it, it seems like the damage is made by accident rather than age. Also these speaker can't be that old I think .... at most 20 ..... rubber surrounds last much longer than foam ...

if the speaker is vented I'm not even sure you have to do anything ... if it's closed you have to patch it up.
the glue you use for patching a rubber tube for a bike might do the job .....


If you find the right rubber surround and change both, they can be as good as new.
The new surrounds will have to be broken in, and over a month you will get better bass than right after the change to the new surrounds.

But seeing the picture I would also first try to glue or patch first, and see how this turns out ..... but changing the surround might make you sleep better at night ;) ..... and it is a fun exercise :D
 
Disabled Account
Joined 2014
Thanks !

To me they look about 10 years old. The surrounds do look quite old though, but based of the amount of dust that were on both when I got them... I can understand why :/ The cut in the rubber does look like an accident though.

These monitors are not vented. Should I only apply a light amount of glue at the back of the crack or paste some tissue over it ? I know Dynaudio use Loctite 30540 for gluing their speakers (so I've read), should it be good ?

Replacing the surrounds will probably let me sell them easier once I decide to (no defect seen) but my worries are that I won't end up with monitors that don't sound (or look) as good... What do you think ?
 
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Thanks !

To me they look about 10 years old. The surrounds do look quite old though, but based of the amount of dust that were on both when I got them... I can understand why :/ The cut in the rubber does look like an accident though.

These monitors are not vented. Should I only apply a light amount of glue at the back of the crack or paste some tissue over it ? I know Dynaudio use Loctite 30540 for gluing their speakers (so I've read), should it be good ?

Replacing the surrounds will probably let me sell them easier once I decide to (no defect seen) but my worries are that I won't end up with monitors that don't sound (or look) as good... What do you think ?

Are you sure? Because I'm pretty certain that both the Dynaudio BM6a and the BM6p (passive version) are vented. The acvtive version has a slot port on the back, above the amplifier section; the passive version has a tube port in the back, at about tweeter height. If they're really not ported, they might be some DIY project, based on the original BM6 models.
 
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