lARrybody

The 100uf Callins caps in my AR91's tested close like your 80's. The 24uf were way off. Interesting to see they are rated 50VDC. I went back with Mundorf E-Cap Plain. I would guess the 82uf and 22uf + 2.2uf in parallel might work. No problems with the lower voltage of these caps so far. I have never herd the 92's but yours are going to be exceptional with the wood veneer. Great acquisition.

Briodo, you have turned those cabinets into a silk purse. They are looking excellent. How did you attach the crossover boards? Get those drivers installed and hook them up.

If the tweeters and mid-range show DC resistance I would sell them separately. More value in parts than the whole speaker and much easier to ship. The cabinets, well maybe somebody in Indiana might want them.

These always seem to have a problem with the venere on the backs. I need to replace the back venere on mine. I wonder if there is a special treatment after the venere is removed and backs sanded. Maybe some kind of shellac sealer?

That is a fine looking AR 11 speaker pictured. I am glad you are enjoying them. I never get tired of listening to mine. The badge on yours appears to be from a AR11A model. The differences between the AR 11A and AR 11B were slight. Different woofers, tweeters and midranges. Different crossovers and different badges and stickers. Again the changes were very small. Sometimes AR had transitional examples because they used up existing parts during a model change. The AR 11B model had a silver screen over the midrange and a model sticker with serial numbers on the front baffle and plastic badges instead of brass badges. Also the crossover switches were in a slightly different layout. That's the easiest way for me to identify them.

As far as the plain E caps verses the raw etched version I don't know the answer. The raw caps are physically smaller, cost less and have a higher voltage rating. I just go by the assumption that if it cost more it probably is better. A Lexus is going to drive better than a Hyundai. Maybe? Maybe not. Anything you use is probably going to be better than original caps. And as Kent has said earlier the lower voltage of the plain caps is probably sufficient. I have used all kinds of caps. I really like the Daytons (5% and 1%), Erse PluseX and other affordable caps. For some reason I am not a big fan of the Solen PB caps. I used Jantzen Superior 2.7uf and 3.3uf paralleled on the tweeter circuit of some 1969 AR3a's. Some Mundorf Supreme caps in AR2ax crossovers. That combination is probably crazy. Maybe I should of saved my money and went with Daytons, but I plan on keeping those speakers. You wont get your money back if planning on selling them. Currently I am on the Clarity CSA bandwagon. I have read that the CSA have a ESR that is closer to the original electrolytes. Also the mylar caps like the Carli are closer, but they are getting hard to find. Unless there is a big problem such as sibilance most caps will work fine. I have these CSA caps waiting to go into a set of AR3's as soon as I figure out what to do about the midranges. They have been matched by Parts Connexion. Someone suggested to me that they may be more relaxed than other caps. That is what I would want for some AR3's. Also I read that Clarity is one of the few manufactures that make their own capacitors. If you plan on going the CSA route I would either parallel two 2uf caps or a single 3.9uf with a 0.1 bypass cap. I personally would use a film cap on a tweeter circuit over a electrolytic. Hope this answers your questions. You really can't go wrong as long as the new caps are close to each other. In my opinion the condition of the drivers are going to make a bigger difference than any cap.

I have used the Jantzen Audio Premium Elko Electrolytic 33uf and 6.8 uf caps wired in parallel for the 40uf cap. You can also use the Mundorf Ecap MLytic 70 in the same sizes. In fact they are the same caps manufactured in the same place. I also include a .01uf film and foil by-pas cap, but that is up to the individual user.

I was driving to the grocery store two Saturdays ago and I pass a garage sale sign. In the spirit of social distancing I slowly pass by looking up the driveway I see two floorstanding speakers that appear to be Advent Prodigy's. Parking and putting on my mask I walk up to take a closer look. They weren't Advents at all, but had AR emblems. They were TSW 510 in relative nice shape. The homeowner said they were inherited from a uncle and there were two smaller bookshelf speakers (TSW 100) to go with them. This was the first pair of TSW speakers I have encountered in person. I knew they were from later on (1989), but they did say Teledyne Acoustic Research on them. Upon negotiation and after a major reduction in the asking price I loaded them into my SUV. Here they are back home. One of the small 100's is missing the Acoustic blanket around the tweeter. One of the woofers on the 510's is different, not a poly cone. I hooked them up to a sacrificial Lepai T-amp and Sony Walkman and they sounded pretty good. The paper coned woofer turned out to be a AB tech replacement. It had a DCR of 7.7 ohms. There was no gasket sealing the woofer in the cabinet. I removed the poly cone woofer and it had a DCR of 3.7 making it a 4 ohm driver. The TSW 510 is rated at 4 ohms. After re-installing the woofers with gasket tape and doing some listening I could not detect any differences in sound or volume from either woofer. How big of difference should a 4 ohm and 8 ohm speaker have? What will this mean to a amplifier? Should I look for the correct woofer? Thanks Larry

Have you seen this thread dealing with ferrofluid replacement?

I attempted to use those same Vishay 1837 bypass caps on a recap project but found the leads to be way to short. I wound up using the Parts Express Film and Foil bypass caps which have longer leads. I ordered some 20 AWG tinned copper wire from Remington Industries and plan on using it to extend the Vishay leads on my next recap project.

Once you get the cabinets sanded I would use the Natural Watco Danish Finish. Be careful with the sanding especially at the edges. The venere is very thin and easy to sand thru. I would start with a 120 grit with light pressure and then go to a 180 or 240 grit. Here are some pictures of some AR2ax walnut speakers with five applications of Watco Natural finish.

Welcome Mike123. Your grandfather left you some quiet desirable AR speakers. As far as I know foam surrounds were not used in AR speakers until 1968 with the introduction of the AR 5. AR 3 woofers used cloth surrounds and usually don't need replaced. Post some pictures of your woofers and someone can help identify them. And yes the caps are located inside the speaker box and probably should be replaced.

Some original pots I cleaned up five years ago for some AR2ax's. After three plus years they started getting drop-outs. Subsequently they have been replaced with L-pads. L-pad installed in a AR4x crossover. This is not my picture or work. You can get these from suppliers like Parts Express and Madisound. On the left is a Ohmite RHS15 R and some ceramic potentiometers currently available on ebay and from others. They are electrically identical to the original aetna-pollack pots but far superior in construction and function. The AR3a restoration guide covers this subject in great detail. http://www.classicspeakerpages.net/library/acoustic_research/original_models_1954-1974/original_models_schematicss/restoring_the_ar-3a/

I have used a Dremel tool with a small round brass brush. Over time I also came to the conclusion that I was wasting my time. There is not much you can do about pitted out disk and wipers. The L-pad or replacement pots are the way to go. Years ago I saw some solid state pots using small resisters and a rotary switch. Does anyone have information about these?

Welcome Ableburger, Here are some related threads that may provide you information on your AR 6 speakers. Pictures of your speakers would be interesting to many of the members here.

I used two 1000uf Bennic electrolytic And one 500uf Bennic electrolytic wired in parallel. Film caps of that value would be huge. The Bennic’s weren’t that small. May I suggest you check the original 2500 and see if it has drifted out of spec.

Here is what I have used for inexpensive 6uf caps. Left (blue) are Clarity PX caps, top (black) Erse PlusX caps, left (yellow) Carli mylar caps and my favorite Dayton 3uf polys paralleled to bring them to 6uf. I have also used much more expensive caps. You can Parallel 2.7uf and 3.3uf Mundorf Supreme, Jansen Superior and Clarity CSA caps. The possibilities are numerous. The Parts Express Electrolytic caps will work fine. I have used the big Dayton Poly caps paralleling 100uf and 50 uf caps for the 150uf and another 50uf and putting them back into the original wax box for the appearance of originality. The Dayton double (parallel) 3uf caps also fit on the original 6uf box.

ADD = Advanced Development Division. Truth in Listening

The tweeters in my AR91 (pn2000029-1) and my AR58S (pn200043-0) are mechanically identical with some slight cosmetic differences as seen in the pictures below. It deffently is possible that the coils and domes are the same.

That tweeter/midrange combo may have been used in other AR speakers. Maybe the AR98ls and 98lsi. Maybe others. I have seen them pop up for reasonable prices. The original tweeters may be repairable with the right dome/voice coil which I see available on the auction site. Eventually something will pop up.

I checked those Korina AR2a's. The corner miters are the same as your Ar2a's

Mundorf Supreme Film Capacitors are excellent. You could go with two 10uf Mundorf Supreme wired in parallel to give you exactly 20uf. My 4x's have Dayton 20uf capacitors and sound excellent. Probably about Fifteen dollars for both. Would the Mundorfs sound that much better. I don't know. I have Jantzen Z-Superior caps on the tweeters on some AR3a's. You could also go with two of them in parallel for Fifty dollars less than the Supremes.

These are my 1963 KLH Model 6 speakers. I think the material under the venere is called NovaPly. Could this be what DonT has? My only set of 2a,s with plywood are the unfinished utility model. All the backs are plywood.

The tweeters can be difficult too. Especially dealing with those delicate aluminum leads. Here are the tools I use. First I run a utility knife around the perimeter of the woofer basket because sometimes the caulk squeezes out and hardens against the opening side walls. I have a small butane heat gun and a electric one. Heat around the basket frame and keep prying slightly at different points. Make sure not to dent the cutout edges or damage the cloth surrounds. The heat should soften the caulk enough that they loosen. As Kent said you can also apply pressure to the back of the magnet. I had a pair of AR12 woofers that someone used Permatex gasket sealer to seat. That damaged to wood baffle getting those out. What you don't want to do. After they are out check the masonite rings at the surround and spider. A lot of times they will need reglued.

Were the grills still stapled on? Great job removing them, not a easy task. It looks like you removed the dual midranges first to get access inside the cabinets. Was there rock wool or fiberglass acoustic stuffing inside? Those oil filled capacitors may be still in speck. I know it is a lot of questions, but I really like 2A's owning several pair. One pair in original shipping boxes with serial numbers 551 and 552. One last thought, be careful with those original grills, that cloth is unobtainable.