Dynaudio refoaming

[soulfuel]

Hi everybody,

I have a pair of Dynaudio MSP80 equiped with 23W75 woofers.

Now the foam surroundings of these woofers are almost completely destroyed and I'm looking for a DIY repair kit for them.

I've crawled a lot over the internet but I did'nt find any specific item for these woofers, and I'm beginning to think that this kind of stuff dooesn't exist.

I would like to know if anyone experienced the same problem and how it were solved (e.g using surroundings for other Dynaudio woofers, or even for other loudspeaker brands).

The solution should be cheap, because the loudspeakers are quite old, and I want to keep them just because they have an emotional value for me and because they look nice, but I would like to know wethere there's something better than the rough solution explained in a previous thread (a cutted rubber surrounding)

Thank you very much for any suggestion!

Best regards,

Filippo

[infinia]

Hi
Link for ordering new surrounds.
http://www.speakerbits.com.au/Defaul...ular%20speaker

Reports that I have read are good for this outfit.

[ashok]

Hi,
Don't restrict your search to foam surounds. You can use a rubber surround also. We had two 12 inch Dynaudio woofers which lost their foam in less than 2 years.
Buying new drivers or repairing them ( export / import , customs etc )were out of the question and we could not find a suitable surround.
The owner found a slightly larger dia rubber surround and the seller told him that all one had to do was cut the surround and over lap the edges to get the right diameter. He said that he had repaired many drivers doing just that with no defective returns.

So.. we did just that. It's two years now and it works fine. The TS parameters were almost like the stock driver. Fs was a shade lower. Could be the mass of the rubber suround compared to a foam surround. However we found no significant change in performance.
I couldn't hear any difference.
( we used rubber based glue like the one used to repair bycycle tubes)
Cheers.

[soulfuel]

Thank you very much for the suggestions!

I was aware of Speakerbits, but according to their catalogue they haven't a surrounding for 23W75. They have surroundings of other similar 8" Dynaudio woofers, but with slightly different measures. I've already asked them if I could safely use these items even if with different measures, but I've got no answer till now.
I'll make a bit more search to hoping to find the right stuff, after that I think I'll follow the suggestion by Ashok...

Best Regards,

Filippo

[nigeljking]

I had a pair of 30W54s refoamed. Due to the non standard size of the cone (ie more like an 11" rather than 10 or 12) they used a 12" surround which they cut and spliced together (very nicely I might add).

I have noticed the bass response has changed considerably obviously due to an altering of the TS characterstics (I would guess a change of resonance and stiffness).

So if you substitute a very diiferent material it is likely the behaviour of your driver will change considerably.

My experience with foam has made me vow to never have a foam suspended speaker again.

Nigel

[infinia]

[i]Originally posted by nigeljking

So if you substitute a very diiferent material it is likely the behaviour of your driver will change considerably.

I would be very wary of just arbitrarily changing a driver surround from foam to rubber, unless you are prepared to re-measure/redesign. The change will affect Qts via Qms, but most likely just a little, depending on Qes dominating. Also damping cone breakup modes via the surround can be altered as well. Not to mention the impact of the dome replacement as is done during this procedure. So both ends of the woofer frequency response and/or sound can be impacted here.

My experience with foam has made me vow to never have a foam suspended speaker again.
[/B]

I hear that, been on the same vow!

[doorman]

Try: http://www.decware.com/newsite/mainmenu.htm
Scroll down to speaker repair.
Don

[ashok]

Not all repairs are the same.
However our rubber surround replacement ( spliced to reduce diameter !) on the Dynaudio 12 inch woofer hardly changed the TS parameters . The TS parameters were measured on the ( stock ) new driver , again after many months of use and then again after the surround was replaced .
It was measured using a CLIO measurement system. We had two drivers and both behaved in the same fashion.

The drivers are crossed over at 100Hz . We heard no difference in performance. I can't remember , but Fs went down by about 1 Hz I think. Don't remember the other parameters but I'm sure it must be lying around on some CDR data backup disc.
It's not important anymore right now. Just get the surround changed - carefully.
I'm almost willing to bet that what ever changes occur to the driver it will be very hard to make out when you play music.
Cheers.

[Lee1234]

try parts express,Used their kit to do my 24W-75 Dynaudios. Kit has 2 different sizes, used the larger.