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hello and restoring my AR3s


wendelljtate

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Hi all,

I have been on here reading a ton over the past month and it is now time to post. I recently came into a pair of AR3s. One of the serial numbers is C08718 and the other is just a couple after that. When I first got them, there was no sound from the midrange and the tweeters went in and out when the pot was turned up and down.

I decided to replace the capacitors and clean the pots which seems to be the norm for these. I replaced the capacitors and used some deoxit on the pots, hoping to get those working without having to remove them. That didn't work so well. So I removed the pots and followed the instructions for cleaning them, including the vinegar and salt bath. They looked really nice. The tweeters work well now but still no mids.

Next, I decided to try to replace the pots with l-pads to see if that would work. I did this for one speaker but still no mids.

Could both of these mids be bad? I feel like my wiring is good. I followed the diagram that matches my speaker numbers (which is B in the AR3 speaker diagrams). I even tried the wiring for C which bypasses the inductor but that didn't work either.

I just can't believe that the mids could go bad...so is my next step to test these mids with a multimeter? If so, how can I do this without taking the speaker out?

Thanks for your help.

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If you have access to an audio signal generator, you could check the response of your mids that way - keep the sine wave level low, and within the frequency response limits of the AR-3 midrange.

You could also download the appropriate test tones here: http://www.audiocheck.net/audiofrequencysignalgenerator_sinetone.php

Transfer the files to your phone, and use it as the audio generator through its headphone jack - again, keep the volume level low.

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Hi all,

I have been on here reading a ton over the past month and it is now time to post. I recently came into a pair of AR3s. One of the serial numbers is C08718 and the other is just a couple after that. When I first got them, there was no sound from the midrange and the tweeters went in and out when the pot was turned up and down.

I decided to replace the capacitors and clean the pots which seems to be the norm for these. I replaced the capacitors and used some deoxit on the pots, hoping to get those working without having to remove them. That didn't work so well. So I removed the pots and followed the instructions for cleaning them, including the vinegar and salt bath. They looked really nice. The tweeters work well now but still no mids.

Next, I decided to try to replace the pots with l-pads to see if that would work. I did this for one speaker but still no mids.

Could both of these mids be bad? I feel like my wiring is good. I followed the diagram that matches my speaker numbers (which is B in the AR3 speaker diagrams). I even tried the wiring for C which bypasses the inductor but that didn't work either.

I just can't believe that the mids could go bad...so is my next step to test these mids with a multimeter? If so, how can I do this without taking the speaker out?

Thanks for your help.

Welcome to CSP...

Many AR-3 mids are compromised to some degree these days. The fragile alumimum voice coil leads are often broken under the metal grill, at the dome, or just under the dome. Repairs are possible, but the use of special solder for use with aluminum is required.

Scrape or sand the paint off the surface terminals and touch your speaker leads to them with something playing at a low level. If there is no sound from the mid, the problem is with the mid and not the level controls.

I have had some success with these repairs. Send me a PM if I can be of assistance.

Roy

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Hi. I scraped the paint off of the front terminals and tried this. I was able to get sound from the tweeter but nothing from the mids. What are my options now?

Repair or replace the mids.

I have repaired a number of these for "Vintage AR", as well as some forum members. I mentioned what the typical problem is in my post above. Otoh, sometimes the voice coil is damaged beyond repair.

Roy

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Welcome Wendell

Best advice: Send the mids to Roy. If they can be fixed he'll do it.

As far as L-pad diagram, attached is a photo (from Roy, I'm pretty sure) that shows the original A-P with terminals B, 1 & 2, and an L-pad with corresponding tabs marked.

Kent

post-101828-0-11537900-1418098037_thumb.

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Another option is to find later AR-3a type mids and install them with a slight crossover adjustment, which would turn your speakers into the last version of the AR-3.

See the last schematic on this page in the forum Library:

http://www.classicspeakerpages.net/library/acoustic_research/original_models_1954-1974/original_models_schematicss/thoughts_on_ar-3_schematics/

Roy

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The AR-3 is almot 50 years old, and there are a number of common problems affecting this model these days. Compromised midrange output is one of them, mostly due to broken voice coil leads and degraded suspensions.

Roy

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Thanks Roy. I have tested both of these midranges in two ways. First, I used my multimeter to test the ohm rating on them. They each barely moved the dial at all. The tweeters on the other hand registered around a 3.5 ohm rating which I hope is good. Second, I put the leads from the amps on the front terminals and heard no sound from either. The tweeters did produce sound when I touched the front terminals.

So I am guessing that my next chore is to remove these and send them to Roy if he has the time...how hard is it to remove these? I read the instructions in the AR3 restoration guide which says to desolder these and gently remove the wire. Is that all there is to it?

Thanks for all of your help so far.

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Yes--desolder from the tabs on the front and remember the leads are DELICATE and BRITTLE. Remove the electrical tape covering the leads. Unscrew the driver and pry it out. There is sealant, like window putty holding it and it may have become rather like cement. Be aware that the drivers are HEAVY. Over 5 pounds if memory serves, so combined with the hair-thin brittle aluminum leads it's a recipe for disaster.

You're in a funny position. Resale prices of AR-3s are ridiculously inflated and if your intention is to sell them you'll have to keep them 100% original. If the old mids are bad and can't be repaired you'll need to look for some on ebay and they will be expensive and probably near the end of their life span as well. OTOH if you want to keep them and have some nice speakers to enjoy you can use later AR mids as Roy mentioned above. The mids in mine are from AR-11 (or maybe 10pi, I forget).

Kent

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Thanks. What are the best options for replacement of these? Are there any modern drivers being made that will work well for the mids? In looking at the specs it looks like it is a 1 3/8 soft dome at 4ohms with the frequency response of roughly 500hz to 4kHz? I don't see anything at PE or Madisound that looks close to this...

I started the desoldering process on one of the speakers last night. I had to pause so that I could borrow a magnifying glass. I can't figure out how the thread is wound to the lead and I don't want to break it like a cave man (which is my natural instinct). It is so difficult to see what is going on there...

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Thanks. What are the best options for replacement of these? Are there any modern drivers being made that will work well for the mids? In looking at the specs it looks like it is a 1 3/8 soft dome at 4ohms with the frequency response of roughly 500hz to 4kHz? I don't see anything at PE or Madisound that looks close to this...

I started the desoldering process on one of the speakers last night. I had to pause so that I could borrow a magnifying glass. I can't figure out how the thread is wound to the lead and I don't want to break it like a cave man (which is my natural instinct). It is so difficult to see what is going on there...

There are no modern replacements for the mids. Refurbished originals, or later used AR-3a/11/10pi type mids are your only options.

There is really no need to be careful with the mids' leads...just snip them. They will be replaced with different leads if you intend to repair or replace the mids. The old leads are wrapped around the terminals several times. You can remove the remnants from the terminals when you are ready to install your repaired or replacement mids.

Roy

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12-10-14 8P.M. EST

Ten or so years ago I was pondering a similar situation and I bought about 18 used AR-3a and AR-11 midrange drivers in anticipation of future blow-outs.

Thankfully the AR3a midrange driver is an amazingly strong speaker and can actually absorb huge amounts of clean power, it still amazes me with its ability after all this time. I’ve read here and there how some people don’t like its sound, but I feel it’s one of AR best efforts!

I’ve only had replaced one and it wasn’t actually blown but , AR thought it prudent when they replaced a tweeter and woofer, back in 1977. I had owned those 3as since 1972 and I was fortunate enough to contact them for replacement and utilize their wonderful 5-year warrantee at the very end of its term, with a few months remaining.

By 1991 I had contacted Mark Levinson looking for tweeters for my four LSTs and he suggested that I contact AR directly to save money. He told me it would be more economical if I purchased them through AR. I remember being so nervous when I actually spoke to the ‘man’ himself as he was already an icon.

I dumbly only purchased two from AR as that was all I could afford at the time.

I was stupid not to buy the full complement of the 16 tweeters I really needed, but the situation at that time demanded I didn’t spend money on ‘old hi-fi stuff’!

I bought more spares later on, they have been sitting quietly waiting and ready, they’re all neatly packed and protected in cardboard boxes and plastic wrapping.

I suggest to anyone who loves these special vintage speakers to stock up and get as many spares of each size of driver as you can afford, while there are available. To this day, I still scour the big auction site and the C-list but, I feel I have enough, so I generally don't buy.

fm

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Thanks for the help guys. I suppose that I will sit back and keep my eyes open for some replacement drivers for these. I am going to move on to my Fisher gear and see how that goes. In the same collection with the AR3s, I was able to purchase a number of other pieces including a Fisher SA300 tube amp and a Fisher CX400-2 preamp. I bought the collection for the AR3s but then found out about how highly regarded these Fisher pieces are. I have been afraid to touch them. I think the time has come to start some testing...

Again, thanks for the direction on the AR3s. I may still take these midranges out and see what they look like. I will post pictures at that point.

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I'm just finishing up my own AR3 restoration.

I bought my pair of AR3's at least 5 years ago and put them in a closet.

A few months ago, I decided to hook them up and start listening to them.

No mids and highs so I opened up the box.

I replaced the pots (cleaned up ones from Roy), closed up the box and was ready for some listening.

No sound coming from the mid-range.

Opened the box, pulled out the mid-range and tested it all by itself.

Again, nothing.

So I sent it to Roy and within a couple of days I received back the resurrected driver.

Now the speaker works like a charm and sounds great.

I can repeat the story above for the other AR3 (also a non-working mid) with the same result.

Roy brought both of them back to life.

A few things to consider:

If you buy 2 used drivers, how do I know what you're getting?

And then you still have 2 useless drivers taking up space.

My AR3 drivers were the original ones so now crossover adjustments were required.

The AR3 mids rarely come up on Ebay and if they do are usually about $70 each.

I hope this helps.

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  • 1 month later...

Hi all,

I wanted to give an update on my project. First off, I want to thank Roy for all of his guidance and help on this project. He has been more than generous with his time and knowledge. He has truly been a life raft for me on this restore.

So I did disconnect the midranges and I did send them to Roy as suggested. Unfortunately for me I am an idiot and didn't pack them properly. They arrived to Roy all smashed and destroyed. Roy sent me the bad news and some pics of the smashed mids. I am attaching those pics. I was pretty bummed with my own stupidity. They are heavy speakers after all.post-174369-0-76796100-1421532927_thumb.post-174369-0-34943200-1421532929_thumb.post-174369-0-91414400-1421533294_thumb.post-174369-0-91311400-1421533295_thumb.

So, in the next couple of days after this bad news, I get another email from Roy. He says that he is snowed in (thank God I live in the south) and that he is going to play around with the mids. By the afternoon, he had performed major surgery on both and had them working. They look great too. I don't understand how this is possible. It is amazing.post-174369-0-22509200-1421533306_thumb.post-174369-0-11818500-1421533307_thumb.

Roy mailed those back to me and I installed them. Thanks again, Roy. The mids sound wonderful.post-174369-0-12433600-1421533836_thumb.post-174369-0-46215400-1421533847_thumb.post-174369-0-30529100-1421533858_thumb.post-174369-0-46582400-1421533868_thumb.

One of the speakers sounds great. The other one has woofer issues. It plays fine when it is on its back but when I install it in the cabinet it gets very muddy, distorted, muffled. I have been emailing with Roy on this and he feels sure that it is an unglued spider ring. I am going to take some time tomorrow and see if I can find a leak somewhere. I couldn't see it today as I was looking. The spider does have a couple of crinkles in it. I am not sure if these could cause the sagging problem?post-174369-0-15644100-1421533887_thumb.post-174369-0-81112400-1421533824_thumb.

I then will have to deal with the cracked black plastic frame on one of the grills.

Thanks again Roy for all of your help.

post-174369-0-16705700-1421533879_thumb.

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