AR2-AX restoration questions (and documentation)

[klamsoss]

I've surfed through many AR restoration threads and have a handful of questions that I haven't seen addressed elsewhere.

First up is where I can source good replacement grille cloth. The cloth on mine are pretty dirty, and the cloth is pretty delicate. One of the frames in busted, too. I'm doubtful about being able to clean them, let alone transfer the disintegrating 50 year old cloth to the new frame I'm cutting.

Second:
What the heck is this black foam on the woofers (see pic) and do I need to try and replace it? Looks like it was more or less scraped off one of the woofers, and is starting to come off the other. I don't see many pictures of woofers with it still on, so I'm a little confused by it.

I'll have more as I make progress, but we'll start here.

 

[bigcaddy64]

Your speakers are very worthy of restoration. I own (2) pairs that have been overhauled 100% and are fantastic sounding for nearly all types of music.

As for your cloth needs, 123stitch.com has the stuff you need (18 count irish linen) has the most authentic look to the original. Its possible you can strip the fabric carefully and let it soak for a day in a bucket of OxyClean. I've brought back some really dirty pieces using this method.


As for the black foam ring, i'm assuming you have early versions with the damping ring around the center of the cone. That was a factory damping device added to "tune" the speaker.


if you can post pictures, the resident speaker doctors can provide a better diagnosis for the patient.

 

[klamsoss]

Sorry about the lack of pictures on my first post, especially after referencing them. Not sure why they didn't upload but they should be there now.

Cool story on this pair:
I bought them off the original owner, a veteran who bought them new at the PX in 1970ish (he wasn't sure of the exact date). He has only moved them 4 times in their life "not counting getting them out today for you, young man". First was when he bought them, when he moved back stateside, when he moved into the new house, and then "they went in this entertainment center 30 years ago and didn't come out again until today."

Consequently, the cabinets are in really good shape aside from some minor discoloration on top. The original info stickers are still on the backs. The discoloration might be able to be polished out, but I'm not too worried about it, actually. These cabinets will look great after I hit them with a fine steel wool for cleaning, and then some oil. I'll probably let my dad do that for me since he likes wood finishing projects.

They sounded great but one of the mid/tweeter ranges wasn't working when the gent fired things up. Fiddling with the pots on the back, I got sound from all drivers. I know these are notorious for corrosion in those pots, so I figured I knew all the drivers worked, and that I had a pair of winners on my hands. I plan do do a crossover rehab, clean the pots or replace them, and do a little wood refinishing in addition to making a new speaker grille frame and probably new cloth for both. We'll see if I can remove the old cloth and clean it without destroying it.

Inspecting them more closely, I have the previous question about the black foam on the woofer... thanks, @bigcaddy64 for the input on that. Sounds like I don't need to try and r/r that unless I hear something weird after the rest of my work is done.
I also have a question about the tweeter on one of these. I have attached a picture of it to this post. It looks almost like it is sitting in there cockeyed or like the diaphragm has been displaced beyond it's normal excursion. Any thoughts?

This weekend I hope to pull the woofers, stuffing and crossovers. I'll do the caps while I soak the pots. Any advice on replacement pots, if it comes to that? I live down the road from parts express, so can pick things up same day.

Thanks in advance for advice, input, heckling, and anything else ya got for me!!

 

[gkimeng]

Are you referring to the gap at the top of the tweeter face plate? That looks to me like maybe someone replaced the tweeter and didn't do a good job of removing all the old sealer and replacing it with new sealer that was soft enough to properly seat the replacement. But if it sounds ok I wouldn't go to the trouble of trying to correct it. It's too easy to break an old AR dome tweeter if you don't absolutely have to remove it.

The current consensus for grill cloth is 18ct Lambswool from 123stich:

https://www.123stitch.com/item/Wichelt-18-Ct-Lambswool-Linen-Needlework-Fabric-18x27/59-135Z

The only thing I've seen that comes closer is a hand woven natural flax linen from Northern Ireland that was ridiculously expensive and perpetually out of stock even before the current pandemic.

 

[bigcaddy64]

The tweeters on those speakers are known to die when the glue dots rot . There are 2 or 3 versions of AR tweeters (3 dot and 4 dot) and all will randomly go bad from failed glue. Its possible yours was just built that way because from the picture the glue looks solid.

Mine looked okay but an inspection with a magnifying glass revealed cracks and separation. Good news is you have options. One is a drop in tweeter replacement and the other is rebuilding. A member by the name of Chris can do them. I don't have his screen name but at some point his name will show up on this thread.

Since you speakers are mint, i would rebuild, if they actually need it.


Caps are fairly easy. Should be 2 total encased in the wax block. I salvaged my speakers pots on 1 pair and replaced another from VintageAR on the auction website. Easy to install and they come with clear instructions so you don't get mixed up. Your going to need the surround sealer as well since you have cloth surrounds. Mine were both foam and completely rotten.

 

[GD70]

Sorry about the lack of pictures on my first post, especially after referencing them. Not sure why they didn't upload but they should be there now.

Cool story on this pair:
I bought them off the original owner, a veteran who bought them new at the PX in 1970ish (he wasn't sure of the exact date). He has only moved them 4 times in their life "not counting getting them out today for you, young man". First was when he bought them, when he moved back stateside, when he moved into the new house, and then "they went in this entertainment center 30 years ago and didn't come out again until today."

Consequently, the cabinets are in really good shape aside from some minor discoloration on top. The original info stickers are still on the backs. The discoloration might be able to be polished out, but I'm not too worried about it, actually. These cabinets will look great after I hit them with a fine steel wool for cleaning, and then some oil. I'll probably let my dad do that for me since he likes wood finishing projects.

They sounded great but one of the mid/tweeter ranges wasn't working when the gent fired things up. Fiddling with the pots on the back, I got sound from all drivers. I know these are notorious for corrosion in those pots, so I figured I knew all the drivers worked, and that I had a pair of winners on my hands. I plan do do a crossover rehab, clean the pots or replace them, and do a little wood refinishing in addition to making a new speaker grille frame and probably new cloth for both. We'll see if I can remove the old cloth and clean it without destroying it.

Inspecting them more closely, I have the previous question about the black foam on the woofer... thanks, @bigcaddy64 for the input on that. Sounds like I don't need to try and r/r that unless I hear something weird after the rest of my work is done.
I also have a question about the tweeter on one of these. I have attached a picture of it to this post. It looks almost like it is sitting in there cockeyed or like the diaphragm has been displaced beyond it's normal excursion. Any thoughts?

This weekend I hope to pull the woofers, stuffing and crossovers. I'll do the caps while I soak the pots. Any advice on replacement pots, if it comes to that? I live down the road from parts express, so can pick things up same day.

Thanks in advance for advice, input, heckling, and anything else ya got for me!!

You have a terrific set of speakers, and from the original owner, a BIG bonus!
So, that tweeter needs to be repaired, it's a common age issue. The little foam blobs let go over time, and there's also a very thin rubber seal around the base of the dome to seal the VC gap. Roy C. rebuilds the tweeters to basically new spec. I would not leave them like that. Roy is one of the co-authors of the AR-3a restoration guide on the classicspeakerpages forum. He's a terrific gent and probably knows AR speakers better than just about anyone. He's been restoring them for a long time.

There's modern pots sold on fleabay if you need to replace your originals.

Most of your other questions have been answered with great advice.

Cheers, Glenn