My Woofer has a Fur Coat - Allison Speakers

[Snade]

The Allison model CD-8 speakers have woofers on top, facing up.

They have collected a lot dust since the original owner bought them in 1985.

The dust has formed a kind of thin fur coat over the woofer. I tried to get the dust off by carefully brushing it with a dry paint brush and got a lot of dust off, but there is still a coat of dust stuck to the surround, cone and dust cap.

I'll probably put new surrounds on them. Any tips to rub off the fur coat without damaging the speaker ?

I picked these up yesterday at a garage sale. They sound very nice - very refined, neutral, well balanced.

Here are photos and some facts about the speakers:

Specs on the Allison CD 8 speakers:

- Allison is Roy Allison and the "A" in AR speakers before starting his own company.

- CD-8, was the #2 (from the most expensive) of 4 models of speakers released by Allison Acoustics Inc. in the early 80's (CD6, CD7, CD8, CD9)

- 3 drivers: 8" woofer, 3 1/2 midrange (Allison convex diaphragm with ferro-fluid damping), 1" tweeter (Allison convex diaphragm with silicone damping)

- 35 lbs and 28 inches tall, each

- 4 ohms

- Allison Acoustics was based in Natick, MA.

- Suggested retail in 1985: $395 each

 

[ARRAY]

I use the CD-6 as surround duty, also with the top firing woofer. If the woofer has some dust on it, so what? It won't affect the drivers' performance (unless it's really caked on & into the gram range). Winters' coming and a little extra cone insulation will help keep your woofer nice an' toasty...

 

[Snade]

I use the CD-6 as surround duty, also with the top firing woofer. If the woofer has some dust on it, so what? It won't affect the drivers' performance (unless it's really caked on & into the gram range).

Right, I got the loose dust off of it, and the low-end sounds very good, so maybe just leave it alone. Thanks.

Snade

 

[onepixel]

Snade,
Nice looking speakers. I have some 4s that have the same hairy problem. I haven't figured out how to completely remove the dust. Doesn't seem to affect the sound.

 

[Art K.]

Very nice pics and great info as well.

 

[soundweasel]

Blue masking tape for de-fuzzing duties

Of the five pairs of Allison CDs (6, 8, and some Model Eights) I've refurbished I used a loop of very sticky masking tape (blue) wrapped around my fingers to brush the dust off. However, I'll bet your woofers really need to be refoamed. Even if the surrounds are intact, they are very fragile and tar-like at this point. Once your remove the old surrounds you can be a little more aggressive removing the fuzz. Also, treat the cones with multiple applications of surround glue thinned with water.

If you think the bottom end is impressive now, refoam them and then be prepared to be amazed! :yes:

 

[ekmanning5]

Mark,
My 4's were the same way. I carefully used a damp cloth to get some of the heavier dust off.
Eventually I just gave up and left them the way they were.

 

[ARRAY]

Right, I got the loose dust off of it, and the low-end sounds very good, so maybe just leave it alone. Thanks.

Snade

Sounds good Snade. If you're able to ignore purely cosmetic issues on equipment this leaves more time for enjoyment of same. Such frame of mind puts you light years ahead in the game. So many out there exhibit borderline neurosis, obsessed with having everything flawless and almost untouched by other human hands in order to feel secure enough with themselves to have a good listening experience.

 

[Fedallah]

My Celestion 11s have the same problem, if you can call it that. Cone mid has some very mild adhesive coating that likes dust. It's not affecting the sound any, so I'm not too fussed.

 

[avguytx]

FWIW, I cleaned the mid/woofers on my Polk SDA's with Windex and either asoft paper towels or a soft cloth of some sort and it worked wonderfully well. They are a "sticky" treated paper cone. YMMV.

Darn nice looking speakers, BTW.

 

[Dan ʕ•ᴥ•ʔ]

I run into this all the time with old guitar amps. I use a vacuum cleaner with the extension hose and the long, soft bristle attachment. Most extension hoses have a valve that you can open to regulate the amount of suction to reduce the risk of damaging the cone. Always works great for me.

 

[Harvey/ Ga]

Right, I got the loose dust off of it, and the low-end sounds very good, so maybe just leave it alone. Thanks.

Snade

Hmmmmm.... how about trying the old masking tape trick?? Sticky side to the dust :scratch2:

Another thought would b a small vacuum cleaner like a dust buster...or, since it looks like you can remove the "cover", blowing it out with some compressed air?

 

[ashevillebob]

This is gonna sound gross, but spit is the best cleaner of delicate surfaces that there is. It has certain enzymes that break down years of grime without harsh chemicals that might damage the glue or even the paper cone itself. I'm not suggesting you start licking your woofer (ha ha), but seriously, conservators of old paintings use nothing but a Q-tip and spit to clean them. If the cone is sticky like a Polk Monitor woofer, I would forget the Q-tip all together and use spit and your finger. Wiping off on a paper towel each time of course. A shot of whiskey during and another after makes the whole process alittle quicker.

 

[cabinover]

Not to mention makes the spittee happier in the process

 

[Paul C]

Use one of those "drier sheets" your wife tosses into the drier when washing clothes. Wipe it carefully and that should get most of it off.

 

[Snade]

Thanks for the great ideas.

These speakers sound fantastic by the way. Allison was not a name on my radar screen, but I'm feeling very lucky to find these things. In particular the mids have this lush sound with excellent detail and the highs are very clear.

These things are keepers and have me re-thinking the value of other speakers in my collection.

 

[soundweasel]

Thanks for the great ideas.

These speakers sound fantastic by the way. Allison was not a name on my radar screen, but I'm feeling very lucky to find these things. In particular the mids have this lush sound with excellent detail and the highs are very clear.

These things are keepers and have me re-thinking the value of other speakers in my collection.

I've always been kind of surprised that Alllisons are not more popular. I really like them because they have great imaging, and their high-end is bright enough (but not harsh) to appeal to someone like me whose ears have seen/heard better days.

As much as I love my Allisons, I still have other speakers I won't part with because they all do sound different than the Allisons, eg my KLHs. Listen to the Allisons, then switch back to some of your others, and enjoy them for their own uniques characteristics. That's all part of the fun! :yes:

 

[Madone52]

CD-8s worth taking back to prime

These are great speakers and worth doing everything you can to get them to optimum levels. Soundweasel is right on. Refoaming a 25-28 year old speaker will always pay off. I have had a pair of CD-8s since 1988, and need to do even more. I need to refoam, replace woofer cones, and grills. That will add up, but should make them good as new.

Time is at a premium, so I may sell, as is, to someone who likes to refurbish.

 

[spkrdtr]

There's an Allison user's group at Yahoo.

http://tech.groups.yahoo.com/group/allison-speakers/

You should be able to get more advice there. There are two experts who respond to questions. One is Howard Ferstler and the other, Roy Allison.

The first time I refoamed a pair of Allison woofers I found the same thing - a fine layer of grey 'felt' on the cone's surface. I thought at first it was there by design, but soon realized it was just an accumulation of dust over many years. That's because the cones and surrounds were originally manufactured with a coating of a very sticky substance that stayed that way for years, allowing dust to pile up.
I wouldn't worry about getting every bit of it off. Anyway, with the added weight of what dust is left, your woofer's resonant freq. is lowered a bit.

 

[ken kantor]

Hi!

1- I recommend a good quality, wide, masking tape. Proper masking tape is made to be removable without damage to the underlying surface, and the dust will come up like a charm.

2- AR stands for "Acoustic Research," not anyone's initials. Roy was not an original founder of the company, though he did become Chief Engineer and is widely considered one of the great designers in the history of loudspeaker evolution. Nice guy, too!

-k