Refoaming Acoustic Research 310HO

[Asmo]

I'm in the process of restoring/refoaming a pair of Acoustic Research 310HO's, all 4 of the 5inch speakers need to be refoamed.
i watched a few dozen videos on how to do it and it seems pretty straight forward but i have a few questions:
1. im pretty sure the original surrounds are made from rubber but im not 100% on it, can anyone confirm?
2. the size is a bit tricky, its not 5inch. i measured about 128-130mm and the cone size is 87mm ID and 95mm OD, does it have to be the exact size or 1-2mm offset is fine?
3. is there a difference in sound between rubber vs foam surround?
4. in the pictures you will see a glue or rubber (I'm not sure) stuck on the cone edge, it doesn't really want to come off easily and stuck on there pretty good, is it ok to leave it or i need to scrape it off
5. glue, if ill go with foam surrounds i know what to get, but for rubber its a bit of a mystery. what do you recommend?

Thank you!

[DavidR]

This model does not show up on Apheno's list which goes up to 1998 with the AR303A. This may be the reason for no posts. Most of us are not familiar with this model.

Here is the history of AR:

In 1967, Acoustic Research was bought by Teledyne, Inc., and for the next 22 years it continued development and operations in Cambridge as Teledyne Acoustic Research. Technological breakthroughs during this period included the high-current amplifier. When purchased by Teledyne, AR was the world's second largest supplier of branded loudspeakers. Although Acoustic Research continued product development, by 1989 AR had dropped to fifth place worldwide, and Teledyne sold the company to their major competitor, Jensen Electronics. In 1998, Jensen, including AR, was sold to Recoton Audio Corporation.

Under both Jensen and Recoton, the AR brand continued development in the speaker industry, including the environmental controls that allowed a speaker to be placed in different room areas, the Acoustic Blanket that minimized diffraction and interference in speaker baffles, and a speaker line designed to complement home theater and the digital technologies of the 1990s.

In 2003, Audiovox (now Voxx International) acquired the U.S. audio operations of Recoton, and continues with AR-brand speaker development and sales. An associated firm, AB Tech Services, provided maintenance of AR speakers until mid 2014. Web-based audiophile communities lamented the closure of the company and apparent liquidation of stock. As of July 2014 CM Tech Support assumed responsibility for Acoustic Research parts and service.

So these were probably made after 1998 by Recoton. Hopefully someone will come along who has some knowledge on them.

[Asmo]

Thank you, i saw one thread by @Pete B hopefully he might have an answer 

[Pete B]

I worked on my friend's pair probably 10 years ago and they didn't need refoaming back then.

I try to clean off old material the best that I can but you have to judge if you are going to

do more damage.  A couple of tips:

I've used a tiny wire brush on a Dremel tool with very good results, go slowly of course,

and I usually stuff old plastic bags under the cone so that all the force doesn't go to the

voice coil to counter the wire brush.  You should also put something directly behind the spot

where you are using the wire brush, I very carefully use a finger.

You could try slicing it off with an Exacto but I'd had mixed results with it.

Last resort is to glue on top of it.

That was regarding the cones, the metal frames are not a problem to clean, scraping with

Goo Off or sometimes Nail Polish remover is better.

I'd call Simply Speakers or one of the other US companies and ask for their advice.

I don't think that, if those were rubber, that type of rubber is generally available and 

therefore I'd go with foam.

There are guides as to what measurements to take to get the correct foam, also tell 

them if the cone side edge is flat, angled, or filled fillet.

I fairly sure that those are coated paper cones, and I'd use Aleen's Tacky glue since it

gives you time to adjust things.

[Asmo]

33 minutes ago, Pete B said:

I worked on my friend's pair probably 10 years ago and they didn't need refoaming back then.

I try to clean off old material the best that I can but you have to judge if you are going to

do more damage.  A couple of tips:

I've used a tiny wire brush on a Dremel tool with very good results, go slowly of course,

and I usually stuff old plastic bags under the cone so that all the force doesn't go to the

voice coil to counter the wire brush.  You should also put something directly behind the spot

where you are using the wire brush, I very carefully use a finger.

You could try slicing it off with an Exacto but I'd had mixed results with it.

Last resort is to glue on top of it.

That was regarding the cones, the metal frames are not a problem to clean, scraping with

Goo Off or sometimes Nail Polish remover is better.

I'd call Simply Speakers or one of the other US companies and ask for their advice.

I don't think that, if those were rubber, that type of rubber is generally available and 

therefore I'd go with foam.

There are guides as to what measurements to take to get the correct foam, also tell 

them if the cone side edge is flat, angled, or filled fillet.

I fairly sure that those are coated paper cones, and I'd use Aleen's Tacky glue since it

gives you time to adjust things.

Hey Pete,

Thanks for the detailed comment, i will try this method and see how it goes.

also, i found these posts: https://www.ukaudiomart.com/details...ho-floor-standing-speaker-set/images/1871174/ and https://www.hifido.co.jp/sold/13-66128-93915-00.html?LNG=E
by the look of it you can say the surrounds are made of rubber? every picture i found of these speakers the surrounds look like that, the leftover surround material of my speakers were gummy and hard and didn't felt like foam. i will try to find some pieces and upload it 

 

[Pete B]

There was an older style, usually Butyl, rubber surround that were quite thick

and are hard to find these days.  If those were rubber, they were more like foam

that was covered with a very thin rubber layer and I've never seen these for sale

anywhere and that's why I suggested foam.  But you should call some of the suppliers

and see what they say.  I'm fairly sure that the owner of Springfield Speakers is on

AudioKarma and there are several pros there that do a lot of work.

I'm not a pro, and what I offered is how I would do it, you should ask your questions

on AK and you might get some better answers.

[Asmo]

Update:

So i ordered a few sets of rubber surrounds and 3 different glues, none of them work unfortunately

Aleen's Tacky glue- was very hard after drying like super glue hard, and didn't stick to the rubber

Aleen's original- same thing

e6000- was better but didn't hold well 

What else do you guys suggest? will polyurethane type adhesive be good? like Sikaflex etc..

 

 

[JKent]

I'm not familiar with those speakers but if they have plastic or plastic-coated cones and the surrounds are rubber, you should use the nitrile-base adhesive sold by many speaker surround suppliers. Ask whoever you bought the surrounds from.

For FOAM surrounds on PAPER cones, white glue like this is the thing to use: https://www.speakerworks.com/Speaker-Repair-Adhesive-Latex-p/l100.htm  Aleene's Tacky Glue is essentially the same thing and I've never heard of it drying "hard like super glue". White glues are PVA and are meant for porous surfaces.

For rubber surrounds and/or plastic cones, use the nitrile based glue https://www.speakerworks.com/Speaker-Repair-Adhesive-p/nr100.htm

Using other glues that were not meant for speaker repair (e.g. e6000) is IMHO a mistake.

[Asmo]

Thank you,

The problem is that i didn't found any company that send this type of glue to my country.

the only similar thing i found is on amazon: https://www.amazon.com/Adhesive-bonding-Between-Material-Instant-Product/dp/B09CV2PHMT/ref=sr_1_3?keywords=Rubber+Glue&qid=1650288671&sr=8-3

 

[JKent]

What country?

[Asmo]

I'm from Israel

[JKent]

You linked something on Amazon. Will Amazon ship to you? This is the stuff:

https://www.amazon.com/Speaker-Repair-Adhesive-Strength-MI-3035/dp/B00L8A9YTO/ref=sr_1_1_sspa?gclid=Cj0KCQjwmPSSBhCNARIsAH3cYgasp3Q1-1Dm4QD6AlH7FCCX8JtjpJMZcIhRJFFXQo5cs8d0V0wTC7oaAseBEALw_wcB&hvadid=313671925378&hvdev=c&hvlocphy=9003579&hvnetw=g&hvqmt=b&hvrand=5383178709710481192&hvtargid=kwd-328626965884&hydadcr=18915_9698718&keywords=speaker+cone+repair+glue&qid=1650300073&sr=8-1-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUExQjhMOEI0MkNZSUJTJmVuY3J5cHRlZElkPUEwNjk2OTMzMVc5QUQ4RlRGNzdLRCZlbmNyeXB0ZWRBZElkPUEwNTczNTY2MkNIQjZLM1lXVU5FWCZ3aWRnZXROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

Did you try these guys? https://www.springfieldspeakerrepair.com/ProductDetails.asp?ProductCode=NRC

I suspect this 3M product "may" work https://www.3m.com/3M/en_US/p/d/b40069393/

Here's a Canadian seller on ebay https://www.ebay.com/itm/293601606906?hash=item445c04fcfa:g:BRUAAOSwpDdVHv~t

Another ebay seller https://www.ebay.com/itm/133503684403?_trkparms=ispr%3D1&hash=item1f15708f33:g:~1oAAOSwcqxfRrnc&amdata=enc%3AAQAGAAAA8LTkuy7pd9Vcyu6HWPdqfjlufFSr8OPNlzyMxRgoWwoNIRSgpiwf0VsGy4WYm3W%2B7FGbK43VeuhthSsRPx1VvWMANGrAV9f0cEJLuOD8RbY4fXm%2FHyZsV48%2B8ZeThAlUoeev7N08699m72v0CKwlD4pXaQkjz%2BHMCfrHpbuTnqwB3WGBp1vAC5hTHe5FtnGWiCsDLYA4fy%2BfUwjH5jyLHXkLpIIXnaOuwuyZPpDn57G2E4molusSkxOSYtA%2FcJIb6FBVH2Lzd0p0yvd0%2FfNZ6vC%2B%2BnIWrYTQdpijpNKtieIUeE9YqT2HytjK1u9YBPimJg%3D%3D|tkp%3ABFBM0KPy2Ydg

[Asmo]

Thank you! yes amazon ships to me but not that specific glue

simple speakers and springfield do not ships to Israel, i have looked at that 3m one but wasn't sure if its good or not

i will contact the Canadian seller he might ship to me. Thanks again 

[Pete B]

Just curious, do the rubber surrounds that you bought match the originals very well?

Where did you buy them?