AR-2x Restoration

[meta_noia_fot]

I recently acquired an early pair of AR-2x speakers. Serial numbers are in the 700's and the date stamps inside the cabinets read Oct. 1964. The masonite rings attaching the spiders and surrounds to the basket have pulled away and one cloth surround has come off entirely. Repairing these is beyond my skill so I'm working on having the woofers professionally repaired.

For now, I'm wondering about the pots. Does anyone know the specs of the pots in these early 2x's and if replacements are available? These pots are larger and of a different design than the ones I've pulled out of sets of 3a's and 6's.

Is there a schematic available for the early 2x? It's relatively simply but I haven't seen one.

I've attached some photos of the speakers and pots. Oddly enough, the pots were each covered with half a Dixie cup with a pack of silica stapled over the opening, then the cup was wrapped in skirt material.

-George

 

Edited January 5, 2023 by meta_noia_fot
Grammar

[meta_noia_fot]

So I decided to go with a tung oil finish based on something @genek recommended in an old thread. I sanded the veneers with an orbital sander, cleaned them with TSP, then applied two coats of tung oil. I'm very pleased with the results. I picked these 2x's up recently and don't have much attachment to them, but I wanted to try out tung oil on these before I redo the veneers on my 6's (which I am very attached to).

[meta_noia_fot]

Hoping for some help on this tung oil finish. I've put the speakers in my attic since I applied the tung oil. I took a look at them today and the color appears much more uneven and blonder than I'd hoped. I'm a novice at this and I'm guessing I didn't apply enough coats.

It's been a week and a half since sanded the veneers and applied the two coats. The finish has been curing since then. Can I simply apply a few more coats? I don't want to sand the veneers again and start over. Anyone have any advice?

Thanks

[genek]

Can you post some pics of what they look like now? Also, what tung oil finish did you use?

[meta_noia_fot]

Here are a few pics. The color seems more blond and uneven than when I initially applied the oil. The coloring on the front top (and rest of the front) is the most glaring. I didn't take pics of all sides, but I'd say these are the worst.

I used a 50/50 mix of pure tung oil from Real Milk Paint and mineral spirits.

 

[genek]

They look the same to me as they did in the pictures you posted last week.

You can't go back and stain over the tung oil finish, and just adding more coats won't make the color any darker.  What you can do is add oil soluble dye to more of the tung oil and then put additional coats on.

https://www.constantines.com/lockwoodoilsolubledyepowders.aspx

Dissolve the packet of powder in a couple of ounces of the same spirit you used in the tung oil and use an eyedropper to add a little bit at a time until you get enough color. Keep the tint light and do multiple coats. Too much at once and you may get uneven coloration.

[meta_noia_fot]

Thanks so much. I'll try that.

Is there a better way I should have approached using the tung oil from the start in order to get a more even color? Looking back on this photo I took after sanding was completed, I can now see how uneven the color is in places like that front corner. Would you use this dye from the start or some other method to stain??

 

[genek]

Make a very dilute mix of dye stain and apply to the bare wood. In places where the color is too light, wipe on more stain in between coats. When the color looks even, then start applying the dye tinted oil to get overall darkening.

[meta_noia_fot]

Thank you. Much appreciated.

[meta_noia_fot]

I followed @genek's suggestion. I used a very small amount of oil-soluble dye and applied what ended up being 6 more coats on the veneers until they wouldn't accept anymore tung oil. One strip on the front is still much lighter than the rest of the veneers but the color overall is much more balanced. At this point, unless there is anything else that can be done, I'm going to take this as a learning experience and classify the lighter strips as "character."

I tested out the electronics and the pots are intermittent. I ordered replacements which should be here tomorrow. My question is about installing the new pots. I don't have a 2x schematic and referencing other schematics like 2ax and 4x didn't answer my question. Maybe someone here can help.

The pot that's installed is not clearly labeled 1, 2, and B as I've seen on other AR pots. Can someone tell me how to wire a new pot (the kind @JKent sells, thanks btw)? In the pic of the pot below, the light green goes to the tweeter and the T terminal, the yellow goes to the tweeter, and the darker green goes to a capacitor. Which of these corresponds to 1, 2, and B?

Thanks

[meta_noia_fot]

Maybe I've puzzled this out...sorry if this is all novice stuff. If I put the new pot in the same place, the terminals should be in the same location with B being the yellow wire. I think I was just overthinking this.

[genek]

You can try dipping a pad in some stain and wiping it along the too-light strip. The color will be laying on top and will be more subject to wear than the finish overall. 

[JKent]

On 1/5/2023 at 2:55 PM, meta_noia_fot said:

Oddly enough, the pots were each covered with half a Dixie cup with a pack of silica stapled over the opening, then the cup was wrapped in skirt material.

Sorry I didn't notice this before. Those pots were replaced once, so you don't have Aetna-Pollack originals. Those are Ohmites. Ohmites are good but as you can see they are open in back and that won't do with the fiberglass stuffing. So there have been several "solutions". Some folks built little boxes. In my case, I used a small plastic project box in my AR-3a's. What a PITA! So I was glad to be able to supply the new, sealed pots to folks like you.

I'm afraid I don't recall how the Ohmite tabs correspond to the A-P but I'll try to do a little research.

[JKent]

Here are 2 pictures of my ar-4x speaker. It's a 2-way like your 2x so essentially the same crossover except for the capacitor value. On the top is the new pot and on the bottom is the original. You can see the layout is the same. So, the Yellow + lead to the Tweeter goes to B. The single Green wire from the external speaker terminal #1 goes to 1. TWO Green wires go to 2: the Tweeter - and one lead from the capacitor.

So it would appear the Ohmites are wired the same when viewed from the back: Yellow to the center tab, one Green on the left (1) and 2 greens on the right (2).

I hope this is helpful.

[meta_noia_fot]

@JKentThank you so much. Hopefully I'll have these playing by the end of the day.

And thanks for the continued help @genek. I may see how much I like these speakers before putting more time into the finish. In any case, there's still a small amount of oil seeping out of the wood, so they'll probably still need a couple more weeks to fully cure before doing anything else.

I'm excited to hear these. I got the woofers back from MillerSound and Bill did an incredible job on them. I picked these up on a whim out of a lot on craigslist and had no expectations beyond seeing if I could get them playing again. Thanks everyone for your help.

[JKent]

Just a thought, and maybe Gene will correct me if I’m mistaken, but I might try Howard Restore-a-Finish, Dark Walnut on the light face frame. 

[genek]

Restor-a-Finish is not a stain. It's designed to soften an existing finish to enable the removal of scale and trapped contaminants. The color is pretty faint. 

Your best bet to darken the face frame is to mix up some additional tung oil with more dye in it and then wipe or brush it onto the lighter wood. Put some painter's tape along the joint so you don't get any on the rest of the cabinet.