MikeD2

Which brings up the next question: how do you know whether to treat or not? I don't have the fancy equipment that RoyC and other purists have. I have not pulled my 3a's apart yet so I don't know the condition of the surrounds in those, but my 4x's seem to be flexible enough, no rot or visible deterioration. The 4x's seem to have a few exceptions to the "general rules" of AR-3a and AR-2ax refurbishing. You can't test the seal on the 4x cones because they were not sealed as tightly as 3a's (according to some other experts here) so the press-rebound test doesn't really apply to 4x's. I do have some of the dope coming from vintage-ar, and will likely use it on the 3a cones, but what about the 4x's?

Thanks. Quick correction. My first pair of speakers are AR-4x's, not AR-2ax's. I hadn't looked at the backs of them for years and just thought they were 2ax's. My 3a's ARE 3a's however. ?

Another suggested trying to use Deoxit5 to clean the original pots. I'm skeptical that will work as intended. I do have a pair of the new L-pads (which I'll save for the AR-3a's) and I don't think I like the idea of taking it down, unsealing the woofer and mucking around again to replace a pair of wonky pots with new L-pads if the old pots don't work. I think I'll go the the new L-pads with no resistor and see what happens. Much easier to add a resistor than to R&R the pots. Also, as a senior citizen, my high frequency hearing is a bit lower than the golden-ear kids who evaluate hifi components. I'm not playing a lot of new, detailed music, mainly older "golden-era" jazz LPs and CDs along with a bit of streamed stuff of random source. Surround dope should be here sometime this week along with the 20 mfd capacitors so next week should see them back together. Thanks for the help!

My initial post was mistakenly appended to an AR-2ax thread, so at @JKent's suggestion, I have started anew. I purchased both my 3a's and 4x's at the same time in 1969 and have begun working on the 4x's for "practice" before tackling the 3a's. So here are some details: These are original purchase speakers, kept in ideal environmental conditions (but not used for a decade or so) and have the AR-4x name plates and serial numbers (see below) so I'm sure they are 4x's (after assuming they were 2ax's in my original comment, having not done my research OR reading the label on the back.) ? I have confirmed from the photos in @Coleman4130's thread "AR4x Crossover Rebuild Check" by @ra.ra(thanks, guys for doing all that work!) that I have the later 2-1/2" tweeters and a single 20 mfd capacitor. (Can't read the numbers with the induction coil strapped on top, but it has 2 wires.) This should be consistent with the date. I have ordered the dope for the cloth surrounds (which look very good) and the 20 mfd capacitor and the 8-ohm 15W L-pads. I'm a bit puzzled by the 25 ohm resistor. I do not find any resistor on the crossover board. My board looks exactly like the photo by @rebelliondog. Other posts concerning the 4x's are saying no resistor is needed between terminals on the L-Pad for this model. With my 1969 speakers, is this the case? Confusing because some of these threads begin crossing over to other models and the trail becomes less clear. And forgive me for being a total dunce when it comes to electronics. I'm a chemist -- we don't like sparks. Cabinets and cloth are in excellent condition and will not receive any amateurish attempts to "fix" what ain't broke. Serial numbers: FX250128 and FX246425 I find this a bit curious because the span between the two numbers is very large. In addition, the FX250128 has the "FX" stamped along with the number, while the FX246425 has a hand-written "FX" before the stamped serial number. Perhaps a rebuild of a defective original, or just a change in manufacture labeling. Interesting. I have not opened the FX246425 up yet so I may find something different in there. I appreciate any assistance you can give regarding the 25 ohm resistor (or lack thereof.) I can send photos if necessary. I cannot read the stamping on the back of the woofer.

Yes, I should do that. Thanks @JKent

Egg on my face!! What I thought (without looking for years) was a pair of AR-2ax speakers are really AR-4x speakers. So I'll change the topic title (if I can) and apply the questions to the 4x. The AR-4x has a 20 mfd capacitor with the inductor coil strapped on top of it. So two questions: Some posts suggest that the 4x cloth surrounds may not need doping. Mine look good but I did not get the slow return when the cone is pressed so I ordered the dope from Vintage AR. If anyone sees anything I'm doing wrong here, let me know. Second, I assume that the same L-pad with 8 ohm resistor works with this speaker as it does with the 3a's. If not, please yell. So sorry about the title. I've had these speakers since 1970 and haven't looked at the back of the speaker for the model number in over 40 years.

Butting in here. I'm "practicing" on my AR-2ax pair but have a pair of 1969 vintage AR-3a's with the cloth surrounds which will be next. Somewhere in here was information on what to use to re-seal those cloth surrounds on the 3a's and a source for the sealant. Speakers are in mint condition and are sealed well, but I would like to re-seal the surrounds with the right material. Can someone point me to the link with that information? Thanks.

Just wanted to say "thanks" to @TomK for taking the time to photo and upload all these photos and detailed information. I'm waiting on parts for my original-purchase AR-2ax's which are likely the same vintage (1970 if memory serves me correctly.) Once the 2ax's are working, my 3a's will be overhauled as well. This is an outstanding forum for novices like me. Thanks again for sharing the experience!

Thanks, @JKent. I need to pull the grille cloth off one of the AR-2ax's and verify that I do have foam speakers -- it has been a couple of years since I had them off. I did purchased them in late '68 if memory serves me correctly. It would be nice if someone would put together a "kit" for these speaker rebuilds. I have pots and foam enroute along with the caps, but from two different sources, and now a third for the resistors. Shipping isn't all that much, but it adds up and a nice kit with foam, pots, caps and resistors would be welcome from a common source and a single shipping fee. But then, I doubt many people are rebuilding them any longer. Sad, because they are outstanding speakers. Checking one of the 2ax speakers, the serial number is FX250128, if that means anything in terms of dating them. Edit: I did pull the grille cloth, and the speakers are indeed foam and look like new. I did order a foam kit so I guess I'll go ahead and replace the foam anyway since I paid for it. The sealer may be leaking a bit, but pressing gently on the cone doesn't seem to indicate much leakage if any. Main problem is the pots and caps, I suspect. They haven't been used in several years and kept protected in a closet, and the pots are scratchy and intermittent as I recall when using them last as rear speakers. Wife didn't like them in the room so they were relegated to the closet. A bit OT here, but I'm using a big Sony STR-D 1015 Receiver driving my AR-3a's (bass only at this time) and a JBL center speaker for the entertainment center. I'm planning on replacing my 5-CD turntable/changer with an inexpensive but good single CD player (need to do some research on that.) LPs are on a Technics SPL-1200 MK2 turntable with a Shure V15 type III cartridge. Good stuff.

Just jumping in here as a total (old) novice and a new member. Thanks to everyone who took time to photo the electronics in the AR-2ax's, as I'm a dunce when it comes to that stuff and need visual confirmation that I'm reading even simple schematics correctly (I am a 75 year-old retired chemist, not an electrical engineer, and all that schematic stuff was always "Greek" to me.) I am just now ordering restoration parts for my two original-purchase AR-2ax speakers manufactured and purchased by me somewhere back in the late '60's, probably around '68. I will try to restore this AR-2ax pair before jumping into restoring my venerable AR-3a pair which have been providing only bass for years on a simple home theater setup. I have ordered new caps and speaker foam for the 2ax's and will go with new L-pads instead of trying to clean the old pots (which I tried to do a couple of years ago with little success on the 2ax's.) My speakers have been kept in normal living quarters temperature and humidity, so no old garage or basement storage problems. Does the manufacturing date matter on either the 2ax's or the 3a's in terms of choosing components? How does one "date" AR speakers and is it necessary, or are techniques applicable to all years/models? In switching to L-Pads, there are several different links to the 25-ohm resistor. Does the power rating matter on these (ranges from 10 to 25W)? And does the tolerance really matter in this application (1% to 10%)? Sorry for the ignorance, and apologies if these questions have been covered in the hundreds of pages here.