Sad day, can anyone help (ar-2ax repair)?

[Guest kdrowdc]

OK, so I want to say up front that I am a rank amateur here. I inherited a pair of 2ax's six months ago; they are vintage late-60s, and were not heavily used over much of that period (they were my dad's....).

They have sounded absolutely amazing (to me - again, I'm no expert), and I've been enjoying them greatly. but tonight I turned them on and it sure sounds like my left woofer is blown. The whole thing still sounds more or less OK, but the left woofer is definitely buzzing, moreso at lower volumes.

Three questions:

1) Did I do this by over-powering it with a modern amp? I am using a Denon AVR-2309. I do not recall hearing anything out of the ordinary last time we used them, but I wasn't listening too closely at the time.

2) If not, then does anyone know someone in the DC/Maryland area who could repair it for me? I've read everything there is to read here and, while I'm pretty ambitious, I've determined that opening and fixing this myself is beyond me. But I'd love to repair them as I love the sound and there is sentimental value as well.

3) Lastly (maybe this is the wrong place to ask) but, if i have to go "new", can anyone recommend a not-too-expensive current-day speaker that can hold a candle to these and have a similar type of sound?

Thanks!

Dan

[JKent]

Hello Dan and welcome!

To answer #3: No--you will not find modern speakers at any kind of affordable price to compare to the AR2ax. And as for #1--probably not. It is very unlikely that your Denon would blow these speakers (unless they were already compromised).

Here's my theory: Early 2ax's had cloth woofer surrounds. Later ones had foam. If yours have foam surrounds, the foam has DEFINITELY deteriorated and MUST be replaced. You may not have noticed a problem with the sound. Here's the bad news: Playing the speakers with shot surrounds could very well cause serious damage to the woofers.

If at all possible, you should try to remove the speaker grilles and have a look at the woofers. If they do have deteriorated foam surrounds it is easy to pull the woofers. You can then ship them to a speaker repair guy such as Millersound in PA or Carl's on CT. Plan B: Check eBay for original woofers (but be careful--there were 2 different woofers used in the 2ax). Here is a site that shows how to remove the grilles. It also shows the early, cloth surround woofer:

http://oak.cats.ohiou.edu/~postr/bapix/AR_2ax.htm

Not all 2ax's had their grilles stapled on. Read the AR3ax restoration manual for tips on how to remove glued-on grilles. It also offers a lot of information that is applicable to the 2ax. It will explain the woofer damage that results from over-driving with deteriorated surrounds, and it shows how to remove the woofers.

http://www.classicspeakerpages.net/library...-3a_full_pd.pdf

If you can get the grille off, take a photo of the woofer and post it here. A pic is worth 1000 words.

Cloth surround woofers had 6 screw holes. Foam surround woofers had 4 holes. Attached is a photo of a 4-hole foam surround 2ax woofer with deteriorated foam.

Here are photos of a 2ax with new foam surrounds:

http://www.classicspeakerpages.net/library...res_from_jkent/

This thread shows a pair of early 2ax's that I restored:

http://www.classicspeakerpages.net/IP.Boar...amp;#entry76370

Kent

[JKent]

Some of those early, 6-hole woofers also had foam surrounds. Please post a picture.

Kent

[Guest kdrowdc]

Thanks Kent. It took me a few days to get back to this, so thanks for your patience.

So, getting those grilles off wasn't nearly as hard as I had thought after reading all the descriptions. The old drywall screw did the trick.

Here are some pictures. Sorry, but I honestly don't even know enough to say if these are foam or cloth surrounds. OK, now looking at your pic, it looks like I have the other type, so that would be cloth. I've got six screws holding the woofer.

Here's the weird thing. I put some low level music through the speakers after taking the grills off, just to see if I could see anything. Lo and behold, lying on its back, the woofer sounded OK. I though "gee, maybe something in the grill was making it buzz", so I stood it upright...sure 'nuff, it started buzzing again. I lay it down again and it stopped.

On further inspection, I can see that the surrounds (or rather the ring holding it in place) seems to be loose at the bottom, but tight on the top.

Any ideas? Thanks so much!

[JKent]

Yes--those are cloth surrounds. So far so good. Those early, cast aluminum frame woofers are good. From what you describe, maybe the surround has separated from the frame. I'll wait for someone more knowledgable weighs in. I don't know if you can just glue it back in place with Alene's Tacky Glue. Stay tuned..........

btw--those "hot cross buns" designs on the ARs are very unusual. I've seen that on some KLH woofers. Good news: Vintage AR, a very reputable dealer, has one just like it on ebay for $69. Search for "ACOUSTIC RESEARCH AR-2ax,AR-2a,AR-2 WOOFER-EARLY PROD" but don't rush to buy it. You may be able to fix yours (see if Roy, John or one of the other true experts offers advice). Or you may be able to remove this one, pack it up properly (including putting a wire from one terminal to the other) and send it to one of the repair shops I mentioned previously. See pp 8-9 of the AR3a manual for removing and packing a woofer, but it also mentions regluing cloth surrounds. I have not done that myself, but someone else is sure to contribute.

Kent

[RoyC]

Hi Guys,

Those 2axs look very nice!

With the cabinet on its back, you should be able to easily glue the ring back onto the basket. It is very common for the masonite ring, to which the cloth surround is glued, to separate from the woofer basket. I have used a number of glues including tacky glue and Goop (messy, stinky, but very tough), and they all have worked fine. Make sure the ring is put back where it was to avoid voice coil rubbing. You should be able to see the outline where it was previously glued. It pretty much "falls" into place. Check the other woofer. It is very possible that the glue has dried out on that one as well.

Roy

[Guest kdrowdc]

Hi Guys,

Those 2axs look very nice!

With the cabinet on its back, you should be able to easily glue the ring back onto the basket. It is very common for the masonite ring, to which the cloth surround is glued, to separate from the woofer basket. I have used a number of glues including tacky glue and Goop (messy, stinky, but very tough), and they all have worked fine. Make sure the ring is put back where it was to avoid voice coil rubbing. You should be able to see the outline where it was previously glued. It pretty much "falls" into place. Check the other woofer. It is very possible that the glue has dried out on that one as well.

Roy

Yes, that's exactly it! The Masonite ring is loose. In fact it is only partially loose.

Should I pry the whole ring off, so I can place a nice uniform bead of glue, or can I just attempt to glue back down the loose part? If I need to take the while thing up first (seems likely), any tips?

Anything else to examine while I've got the guy on the operating table?

[JKent]

Well this is good news! You can repair the speakers cheaply and easily . Roy mentioned the plusses and minuses of Goop. You can get a small tube in a hardware store. They sell several different varieties: For plumbing, for shoes, etc. AFAIK they are all the same. Alene's Tacky Glue is sold in craft stores and fabric stores (and Walmart). It is similar to Elmer's glue but, well, tacky. It is water-soluble and easy to work with. I have not performed this particular operation but I would be inclined to use the Alenes, just pry up the loose part and push it under as much as possible, clean up any excess with a damp sponge or rag. The Goop will do a good job but is less forgiving. It is extremely sticky/gummy, solvent-based and nearly impossible to clean up. OTOH it wears like iron. I used some to repair the sole on my hiking boots.

You probably do not have to reglue the grille board--it may stay in with friction. If not, I recommend getting some Velcro and putting the grille on with that. One small square or disc in each corner and one in the middle should do. Then you can take the grille off if you ever decide to do more work.

How much to do depends on how satisfied you are with the speakers and how much you feel like doing. Weak points are the level controls ("pots") on the back. They are notorious for corroding. Many people advocate replacing the capacitors (caps) inside. These projects are not difficult and there are people here to help. Again, read the excellent AR3a restoration guide. It will tell you about the pots and caps. On the 2ax the pots can be replaced with inexpensive L-pads if you don't want to clean them up. The crossover (pots, caps etc) is simpler in the 2ax. In this thread is a photo of a 2ax crossover I rebuilt. It has new caps (those little black or yellow tubes) and L-pads (the silver things labeled HI and MID. The inductor (big spool of wire) does not get changed).

http://www.classicspeakerpages.net/IP.Boar...amp;#entry73966

If you don't want to tear into them, just twist those level controls clockwise & counterclockwise several times to scrape off some of the internal crud, then set them where you like them and listen to be sure you are not on a dead spot. They will be fine.

If you decide to do any cosmetic work to the cabinets or grille, again check the 3a manual. My suggestion: If the grilles look OK just leave them. If the cabinets are good but maybe have a few scratches, try a product called Howard's Restor-a-Finish.

Good luck, HAVE FUN and happy listening!

Kent

[Mazeppa]

On further inspection, I can see that the surrounds (or rather the ring holding it in place) seems to be loose at the bottom, but tight on the top.

Has anyone suggested rotating the woofers 180 deg? Part of the surround's job is to center the cone. In the pic it looks like yours may have sagged downward over ther years.

[Guest kdrowdc]

Has anyone suggested rotating the woofers 180 deg? Part of the surround's job is to center the cone. In the pic it looks like yours may have sagged downward over ther years.

Ah! You may be on to something here, because I glued the rings back on, but the fuzz in the woofer is still there - only when the speaker is standing up. On its back, it sounds fine. This would be consistent, I think with "sagging down", no?

It definitely sounds like something is touching the driver, or the baffle or something in there and causing it to vibrate. In fact (I'm sure this is a no-no), I can stop the buzzing by gently touching the cloth surround with a finger.

I assume that rotating would entail more than just unscrewing and rotating - would I have to re-wire the speakers? I suppose the next step is to extract the woofers and maybe post some more pictures. I've read through the 3a repair guide, so I've got a decent idea of where I'm headed - but I admit its been about 20 years since I've used a soldering iron back in EE school.

Thanks for the support and help, guys!

Dan

[JKent]

Bummer. I don't know if the rotation is really a fix, but yes--just pull the woofer and turn it 180 degrees. You should not have to rewire anything. The biggest problem will be removal: It is set in black goo that holds tenaciously. Save it if you can. You can roll it into a ball like modeling clay--the warmth of your hands will soften it. Then reuse it. You can also use "duct sealant" from the electrical dept of a hardware store or Home Depot. It comes in a chunk the size of a brick and will last forever.

btw--don't be surprised if the red wire is attached to - and the blue is attached to +. If it is, don't change it.

Kent

[Pete B]

Those woofers are so old that it is very common for the glue to have become dry,

brittle, and often starting to detach. It is suggested to rotate those woofers 180 deg

in a situation like this and you can test this fix by playing the speaker upside down

first. I suggest that when you remove the woofers that you apply some pressure

around the spider to determine if the glue is intact and repair the joint if not.

[JKent]

If the rotation does not do the trick you probably have a sagging spider or a damaged voice coil. If so, you can buy that replacement from Vintage AR or--better yet--send the woofer to Bill LeGall:

http://www.millersound.net/about.htm

Good luck

Kent

[Guest kdrowdc]

Woofer rotation did the trick!!!!

I tried the "play the speaker upside-down" test, and sure enough, it played nicely upside down. After a five minute debate with myself over just leaving them that way :-) I just decided to dig in and give it a shot. As Kent said, the hardest part was getting the drivers out of the putty holding them.

I had almost given up, when I realized that I needed to remove the visible putty between the driver edge and the wood (I used a teeny screwdriver to scrape it away..but kept it). I still couldn't figure out how to lift it out of the hole, when I just grabbed the metal between the screw-hole and the edge with a needlenose pliers (carefully, gently) and pulled straight up. The driver came right out. I am not recommending this method..I'm just letting people know how I did it, since it was non-intuitive!

Anyway, the speakers are now playing nicely! I may need to go back in and ensure I have a good seal by adding some new putty, since there didn't seem to be enough to put back to make a good seal, but they sound just fine right now, with nice rich buzz-free bass. I think tomorrow I'll do a preemptive rotation on the second speaker as well.

Just a quick aside to any other newbies out there - this was way easier than it sounded after reading the fantastic, detailed but sometimes daunting guides. Even if the answer was to replace the whole driver, the operation would have been easy, and well worth the effort. I was literally on my way to find a new pair of speakers, but now it seems i've got my 2ax's back!

Thanks to everyone here for their wonderful help and encouragement.

Dan

[Mazeppa]

Woofer rotation did the trick!!!!

I tried the "play the speaker upside-down" test, and sure enough, it played nicely upside down. After a five minute debate with myself over just leaving them that way :-) I just decided to dig in and give it a shot. As Kent said, the hardest part was getting the drivers out of the putty holding them.

I had almost given up, when I realized that I needed to remove the visible putty between the driver edge and the wood (I used a teeny screwdriver to scrape it away..but kept it). I still couldn't figure out how to lift it out of the hole, when I just grabbed the metal between the screw-hole and the edge with a needlenose pliers (carefully, gently) and pulled straight up. The driver came right out. I am not recommending this method..I'm just letting people know how I did it, since it was non-intuitive!

Anyway, the speakers are now playing nicely! I may need to go back in and ensure I have a good seal by adding some new putty, since there didn't seem to be enough to put back to make a good seal, but they sound just fine right now, with nice rich buzz-free bass. I think tomorrow I'll do a preemptive rotation on the second speaker as well.

Just a quick aside to any other newbies out there - this was way easier than it sounded after reading the fantastic, detailed but sometimes daunting guides. Even if the answer was to replace the whole driver, the operation would have been easy, and well worth the effort. I was literally on my way to find a new pair of speakers, but now it seems i've got my 2ax's back!

Thanks to everyone here for their wonderful help and encouragement.

Dan

Glad to hear your AR's are going again. For my part in the process I really should say that all I did was repeat what I had read elsewhere in the forum. This really is an outstanding source of information and help.

Speaking of help, I have a pair of 2a's that the woofers have resisted my best efforts to remove for the purpose of recapping the crossovers. Will try your method of removal on my next attempt.

Mazeppa

[JKent]

I have a pair of 2a's that the woofers have resisted my best efforts to remove for the purpose of recapping the crossovers. Will try your method of removal on my next attempt.

Read p 8 of the AR3a repair manual:

http://www.classicspeakerpages.net/library...-3a_full_pd.pdf

Also be sure to work in a warm room. Maybe even warm the metal frame of the woofer CAREFULLY with a hair drier. It is more pliable when warm.

Good luck.

Kent

[Shacky]

Those are the older version 2AX that I much prefer. Mine responded very well to recapping. Next time you feel ambitious, take the woofers and stuffing (carefully keep each speakers stuffing in a bag for re-use), repalace the mid and tweeter cap, clean the attenuators and sit back and enjoy for another 30-40 years!