AR 2-A SCORE and questions...

[GD70]

you guys werent joking about these speakers requiring patience to remove the grilles !!! . these staples are tiny!
... i havent tested the speakers yet... but do you guys see anything alarming here? im confused about the process of revamping fabric surrounds....
to me... so far on the first speaker it looks better inside the cab. than i expected....

there was no way that grille was coming off without removing the cloth first...... i hope thats ok lol... i was careful to keep it in good shape... .

broke one of the "hatpin" insignia... but it looks like it can be resoldered ....

The drivers look great! Did you do the air tight test prior to pulling the cab?
If not, do it on the other speaker before you remove the drivers. Gently push the woofer in and watch how quickly it moves back out. It should be slow, 1-2 seconds, not immediately. If slow, you have good air tight surrounds, if it popped out quickly, the surrounds need resealing. Mine were pretty good and slow, but when I held them to the light, I could see little spots where light came through so I sealed them. I feel it doesn't hurt to reseal them, and then you know you're good for another 40 years.

Glenn

 

[stumptacular]

The drivers look great! Did you do the air tight test prior to pulling the cab?
If not, do it on the other speaker before you remove the drivers. Gently push the woofer in and watch how quickly it moves back out. It should be slow, 1-2 seconds, not immediately. If slow, you have good air tight surrounds, if it popped out quickly, the surrounds need resealing. Mine were pretty good and slow, but when I held them to the light, I could see little spots where light came through so I sealed them. I feel it doesn't hurt to reseal them, and then you know you're good for another 40 years.

Glenn

great news!... i got the sense that these speakers have never been opened...
havent got the front grille off the other one but im gonna try the airtight test... THANK YOU!... ive already bookmarked your restoration thread... i will read it closer after i get more done on these tonight... if the pots work can i just cover the front with cardboard etc while i sand and refinish the cabinets? or should i take everything apart and recap it no matter what?

***can you tell me how and what i need to do to reseal them?

 

[GD70]

I'd recap regardless if they sound good. Those caps are nearly 50 years old!

 

[GD70]

I'd recap regardless if they sound good. Those caps are nearly 50 years old!

eBay seller vintage-ar sells the sealer.

 

[stumptacular]

eBay seller vintage-ar sells the sealer.

shouldnt i likewise reseal them whether needed or not? would the same glue for a refoam work for a sealer? i have plenty of that? (rookie questions i know... sorry lol)

 

[RxDx]

Your BGW amp looks like exactly what you need for the 91s- unperturbed by a
massive 4 ohm load.

Refoam glue is just glorified Elmers. Fabric surround sealer is a whole different
animal- butyl and toluene, which would melt foam. Yes, give the woofers a
treatment.

 

[michiganpat]

shouldnt i likewise reseal them whether needed or not? would the same glue for a refoam work for a sealer? i have plenty of that? (rookie questions i know... sorry lol)

nope, it will stiffen the surrounds too much and raise the woofers Fs, kill low end and make the bass boomy....the proper sealer IIRC is a butyl/tolulene mixture that doesn't stiffen the surround

 

[stumptacular]

thanks guys... step by step... im stoked to see the drivers all looking good... still havent tested it... but i did get the grilles off... will be interesting to see if i can possibly salvage the original cloth... these speakers appear to have never been opened... but it seems there are two pins on either side of one of the cones... can you see those tiny silver dots in the one woofer cone??? whats that all about?

 

[stumptacular]

Your BGW amp looks like exactly what you need for the 91s- unperturbed by a
massive 4 ohm load.

Refoam glue is just glorified Elmers. Fabric surround sealer is a whole different
animal- butyl and toluene, which would melt foam. Yes, give the woofers a
treatment.

thanks Ken... i need to do more homework and figure out what kind of preamp would really compliment the BGW amp... i need options
i suppose while im waiting on the sealant i should get to work on sanding the cabinets.... i really hate to take these speakers all the way apart... but if a recap and a pot cleaning is vital to it i may as well... i just dont have much experience with these sorts of repairs... have to take a gloser look at GD70s restoration and see how he solved these problems .... i appreciate the feedback as i restore these things... i hope to enjoy them for awhile

 

[GD70]

shouldnt i likewise reseal them whether needed or not? would the same glue for a refoam work for a sealer? i have plenty of that? (rookie questions i know... sorry lol)

Only use this sealer, period. A lot of time and testing was done developing it, it's the closest sealer to the factory stuff you can get.

Once you're done with these, you'll have a great sounding pair of speakers.

 

[stumptacular]

ok... so i tested the speakers... they all work...sound pretty amazing on a quick preliminary test.... the pots are a little dirty... true.... but... is recapping so vital that i must remove these drivers ? it seems like i could just reseal the woofers and refinish the exterior of the cabs without having to strike the match and go down the hatch into the capacitors and pots.... is it worth it? why or why not?

 

[GD70]

ok... so i tested the speakers... they all work...sound pretty amazing on a quick preliminary test.... the pots are a little dirty... true.... but... is recapping so vital that i must remove these drivers ? it seems like i could just reseal the woofers and refinish the exterior of the cabs without having to strike the match and go down the hatch into the capacitors and pots.... is it worth it? why or why not?

You're call really. Most would suggest recapping them.

Read through the 2A restoration thread. You'll see it's fairly straight forward.
The pots is a whole different issue. If yours are working properly, that's pretty rare. They almost always have some corrosion limiting their operation. If they are sounding good, then cover the baffles, sand the cabs and refinish and enjoy.

Glenn

 

[stumptacular]

i have to find a sweet-spot for the pots to work... but.. im not sure im all in that far on this restoration but... "a job worth doing is worth yada yada ..."

taking them all the way apart would surely make the cabinet refinishing an easier task no doubts....

im definitely reading your restoration thread GD70 i appreciate your input for sure

 

[stumptacular]

You're call really. Most would suggest recapping them.

Read through the 2A restoration thread. You'll see it's fairly straight forward.
The pots is a whole different issue. If yours are working properly, that's pretty rare. They almost always have some corrosion limiting their operation. If they are sounding good, then cover the baffles, sand the cabs and refinish and enjoy.

Glenn

ok GD ... im in ... i decided i will take on the task of a full restoration but i have a few questions if you please...

1. can you please list the exact replacement parts i need ....
A. the sealer for the surrounds (brand, product?) and where to get it
B. the exact caps i need for replacement/upgrade and where to get it
C. the exact pots i need from parts express
D. a link to the fabric you use

2. i noticed that my cabs must have veneer under the paint as some de-lamination has occurred where the speakers were stored in a basement on their end....
A... can i use a paint stripper to make this paint removal easier? if so what?
B... how can the delamination be repaired?
C. is taking all the veneer off an option?

3. I read in your thread that the new pots arent wired the same as the old ones?? can you give me any hints on that ???

i would really appreciate if you could take the time to help answer these questions for me... it would be a HUGE help...

 

[Drugolf]

Ah yes, the good ol sweet spot in the pots routine. Oh so familiar to all AR owners.
Gotta take em out and hope they aren't too far along. There are options if they are.

 

[stumptacular]

Ah yes, the good ol sweet spot in the pots routine. Oh so familiar to all AR owners.
Gotta take em out and hope they aren't too far along. There are options if they are.

im just gonna recap and replace the pots as long as i can figure out what goes where lol.. the veneer / sloppy paint job on the cabs kinda scares me.. i wonder if worse comes to worse if i can just take them all the way down to plywood and enjoy them that way... or possibly re veneer them... apparently this project might take aawhile.... "vintage-AR" on ebay is on vacation until late feb... so im hesitant to order from him... (i need the sealant for the cloth surrounds) ....

the good news is.. i live 15 minutes from parts express

 

[stumptacular]

here is a pic of the delamination issue....

i think saving the veneer might be more trouble than it's worth... what do you guys think?

 

[c5corvette]

From my experience, I would test some paint stripper on the bottom of the cabs. Quite effective if used as directed and safely, like outdoors. Sanding down a painted finish can be tedious and tricky depending on thickness of veneer. Just cover or remove drivers before applying.

 

[GD70]

here is a pic of the delamination issue....

i think saving the veneer might be more trouble than it's worth... what do you guys think?

Looks like these had some moisture exposure. You can see little mold spots on the paint. Try both chemical stripping, and sanding small spots to see which works better, then go the way you feel most comfortable. If you decide to sand, you'll need a small hand power sander.

I'll post a list later today for the grill fabric, the L-Pads if you need to replace the pots, and caps.

Glenn

 

[stupidhead]

the little dots are the leads to the cones, don't fuss with them. Yes, this will take some time, and as I said before likely you will put more time and energy into them than you would recoup if you were to try and sell them. Think of them as a set to cut your teeth on as it were.

Where to go next? I notice some paint peeling cleanly off some areas which possibly suggests an oiled surface before painting. The pic of the backside is inconclusive, but I think I see veneer on plywood or mdf or solid but veneer application does seem to be there. I would cut out some cardboard and cover the drivers for now and evaluate the cabs further. The fact that you have verified (at least on one) that you have original drivers is a huge plus. Again, be very careful of the opposed mids, they are extremely delicate, as are the wires to the front terminals on the tweeter.
You should be able to inspect that back edge and determine if in fact there is veneer.... on three sides or four? Paint removal is a trial and error thing, but shouldn't be all that tough once you determine an effective approach. I would caution you on sanding as the veneer is quite thin.

By the way, you appear to be missing one of the knurled nuts on one of the terminals, these are generally available through a variety of sources such as Vintage AR and others.
As for the doping of the surrounds, that can be done later, but do not use anything you may read about as an alternative other than the stuff sold by Vintage AR. There is no "brand" as it is a concoction made by member RoyC and is as close to original as can be. Other products will stiffen the cloth over time and lead to unsatisfactory sound reproduction, and the surrounds are ruined if used.

Cap replacements can be a matter of contention and there is no absolutely right brand to use. I believe there is a 4uf and 6uf in that xover and many possible vendors. You could spend .50 or $50 per cap, many people are of the opinion that boutique caps are not worth the extra money, I personally find a quality mid grade cap for my work.

As for pots, well you don't know yet if you need to replace them or just clean them. Hopefully just a cleaning is all you need, but there are a few options available if need be. Bottom line is do not just by-pass them.

Geoff