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What is the doping material on Altec 416-8a speaker edges - where to get it?

Bradmich

Bradmich

New Member
Hi there!

I'm re-coning a set of 416-8a speakers - using the kits from The Speaker Exchange. The pleated edges do not come with any doping material applied. As I understand it, Altec used a viscoelastic damping compound. The only thing I can readily find is Green Glue?

Any Suggestions on what I should use and where to buy?
(I read about AR Vintage via ebay on other threads - however they no longer sell it)

Thanks! Mark
 
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Hi Team,

Truly Appreciate the replies!
FYI: GPA no longer offers materials to my knowledge and the VPAs by other vendors are not the same chemical composition or deliver the same long-term characteristics.

I spent a few more hours web surfing and found this: https://www.ebay.com/itm/276727492465.
It's closer to the chemical compounds of the original formula. Gonna test it and see - will post the results.

Building a new and improved set of VOTTs w/wings! this time (Set #6) - should be complete in the next month.

Altec1.jpg
 
Are you doing the work yourself?
I did 10 last year with the Speaker exchange kits.
I used the goop mentioned above by Bowtie

It will be interesting to hear your impressions of the Aquaplas. I didn’t know about that stuff.

The AR dope Mission mentioned wasn’t available.
 
Hi RonSSNova,

Yes, doing it myself - using the same kit you mentioned. Interestingly, their voice coil appears to be a bit larger (taller) than stock.

Thanks- Mark
 
As Ed McMann used to say on the tonight show, "You are correct sir."
Some math will be involved to get their coil centered in the gap in the in/out direction.
I also did my duplexes. It's the same parts.
I did a write up over on HiFi Haven you might check out.
And, welcome to AK!
 
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You may find this hilarious...

After positioning and glueing the first VC to the spider, I was ready to start on the 2nd. I looked for like 30 minutes and could NOT find the 2nd spider- what the? I paused then mumbled "f*%k me" to myself as I realized I glued both spiders together on the same coil... I thought it seemed like an awful thick spider! :)

Note to self: Order (2) more Spiders and one new VC.
 
OP, I haven't seen the proper solvent based damping compound for sale in over a decade. I used up my last quart can of it last year. I think we're stuck with the water based crapola now.
 
FWIW, there were different dope formulas for different applications.

My understanding is that Altec used at least 5 different compounds over time, the first of which was specifically for treating paper hinges, and that formula was still in limited use thru the mid 70's, it's last hoorah probably being the mid-compliance on the 419 and 420.

At least one formula was engineered to be a sealant only, no damping characteristic if applied properly, like the stuff you'd find on an original un-molested 416-8B for instance. Other formulas were intended to both seal and adjust the compliance of the pleated cloth surrounds.

Sadly, much like the replacement moving parts, service supplies for Altec drivers have long been reduced into a one size fits all existence.
 
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8 OEM cone assemblies just sold on eBay for $1k. Beyond my pay scale. Was actually not a terrible price.
No dope included.
Bill H sent me a big bottle of the dope many years ago when he sold me 4 cones. I must have let it go when I sold two of the cones and 416-8B baskets a number of years ago to Mattvandyke who posts here from time to time.
Those -8B were in A7’s I bought new in the box in 1978. I recall they had shiny sticky surrounds. Although my recall is less than stellar.
 
RonSSNova said:
8 OEM cone assemblies just sold on eBay for $1k. Beyond my pay scale. Was actually not a terrible price.
No dope included.
Bill H sent me a big bottle of the dope many years ago when he sold me 4 cones. I must have let it go when I sold two of the cones and 416-8B baskets a number of years ago to Mattvandyke who posts here from time to time.
Those -8B were in A7’s I bought new in the box in 1978. I recall they had shiny sticky surrounds. Although my recall is less than stellar.
Click to expand...
I could be wrong but I believe that I bought the Altec 414's from you and not 416B's and don't recall a big bottle of dope (the stuff I used to buy came in baggies:)). I will look around here to check. It could be my recall also Ron
 
bowtie427ss said:
... and that unique, wonderful smell that only a new Altec speaker had. ;)
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I don’t know what they smelled like new, but all my Altec speakers have a certain smell to them.

People probably think it’s weird that I sniff speakers. I sniff old books also. And firewood/lumber too. I can usually tell a tree species by the smell of the cut wood

To me, smell memories are some of the strongest.
 
mvandyke said:
I could be wrong but I believe that I bought the Altec 414's from you and not 416B's and don't recall a big bottle of dope (the stuff I used to buy came in baggies:)). I will look around here to check. It could be my recall also Ron
Click to expand...
They were 416-8B bare with the GPA cone kits. I didn’t have the balls to try the recone myself. I had Jmac do the -8C and thought they were fine.
The dope I just don’t remember. It did sit in my kitchen cupboard for quite some time though. Pretty sure I didn’t mistake it for hot sauce….
 
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