AR-3a Improved, Are they worth repairing??

[Juan9568]

Hi guys, I'm new to the site. I've been reading a lot about these speakers but I still haven't got the opportunity to test them at full potential.
This is my situation. I got from my uncle his pair of AR-3a improved dated July 28th 1986 (or what is left from them). They where stored in terrible conditions, misused with an 8 Ohm Sansui 9090DB receiver, and "serviced" lately by a killer technician. The tweeters and mid range drivers are gone. Crossover circuits has been "bypassed" (killed). Both woofers are alive, they just need a refoam.

Do you think is it worth to restore them? or it would be a total waste of money? I love the woofers on these ones, I wouldn't wanna throw them away...

I would need to rebuild the crossovers and get the replacements for both tweeters and mid range drivers.

 

Here are some pictures

[JKent]

No--not worth it. Send them to me and I'll dispose of them 

Welcome to the CSP! I think you have a couple of options: Easiest thing would be to sell the woofers and the the crossovers and put the money toward some other speakers.

The other option, if you feel up to the challenge and an addictive new hobby would be to undertake a restoration. First step would be to download and review the AR3a restoration guide linked at the beginning of the AR section. Then you'd have to refoam the woofers, restore the crossovers, replacing those 3 black caps, find some 3a or 10Pi or 11 mids and maybe the Hi-Vi tweeters, Then there will be some work fixing up the cabinets. It's a big project but can be quite rewarding and I'm guessing you have some attachment to these, since they were your uncle's.

Lots of help available here.

btw, that "technician" should be publicly flogged!

-Kent

[Juan9568]

Thanks Kent!

Does the AR-3a and Improved version share the same crossover??

I'm still thinking of selling the woofers but I don't wanna do it yet. It depends on how much money I'd need to use for the restoration. I'm could spend up to $600 or less, not more.

Is there any OEM or alternative drivers that I could use ??

Getting originals is nearly imposible for me as there's no market for where I live.

Thanks!

Juan

[JKent]

Hi Juan

RoyC is the guy to talk to. The 3a Improved crossover is different. Here's a schematic 

 

And the cabinet is different, and the grille (do you have them?) and the logo. But 90% of what's in the 3a restoration guide is applicable.

As for drivers, you can use the later mids I mentioned (10pi, 11) and there may be more. AR-3a mids can be about $150 each but the 10pi and 11 are identical and seem to sell for under $100 each. I don't know what other AR mids may be appropriate. The Hi-Vi tweeter is a good replacement and inexpensive. If you are doing the work yourself a rought guess would be $200-300 for the mids and tweets, maybe $50-75 for the capacitors, $20 for a set of woofer foams (or maybe $100 to have Bill LeGall do them). Those are very rough estimates. Again, Roy is the guy to talk to. He may have most of the parts you need, can give expert advice, and is also very qualified to refoam your woofers.

Also look at this thread. John O'Hanlon (johnieo) knows a lot about this speaker. He mentions that the Improveds did not use the same tweeter as the original 3a. It's a ferrofluid cooled model, pictures A-22 or A-24 in the AR-3a restoration booklet. He also mentions that AR-10pi and AR-11 tweeters Are perfect replacements. Google "AR-3a Improved" and you will find more good info.

Where are you located? There may be a CSP member close by who could help.

-Kent

[JKent]

Here's a more accurate breakdown:

The 150uF cap may be fine. Here are Madisound prices: A new Bennic 150uF NPE is $3.70. Carli Mylar 20uF is $5.95, 10uF is $2.75, 6uF is $1.80. So about $16 worth of caps per speaker. Hi-Vi Q1R tweeter is $18.80. You need a coil with that, 0.05mH I think (it's .05 for L-pads, .07 for pots. The improveds have switches so I'm not certain. Madisound .05mH is $2.30. 

Your existing coils and resistors are fine. The switches are probably fine but may need a bit of De-Ox-It.

As I said, mids sort of depend on the whims of ebay OR if you can get some from a CSP member. I see two 10pi mids on ebay now for $90 each (I have 10pi mids from Roy in my 3a's). Add in new foams and your total cost could be ~$300 for DIY or ~$400 if you send the woofers out.

The cabinets will be a challenge. CSP member Glenn is the expert on patching veneer. Or if you are less fussy you can make some good repairs with walnut color Mohawk epoxy sticks.

If the grilles are gone you can make new frames. I don't know what the original fabric looked like but there are many choices in that department. I "think" the originals were linen, like the 3a and if so the best choice is the "lambswool" color 18 count linen from 123 Stitch. It's a little pricey but beautiful. It also comes in other colors. A cheap substitute is 28 count "Irish Linen" cross-stitch fabric from Michael's craft store. It's about $8 a roll. You need 2 rolls and there are always 40% off coupons available. Or, the euro-look Improveds may be nice with black cloth. Best choice: Let the wife pick out the cloth 

-Kent

 

[Juan9568]

Thanks for all this info, this is really helpful!

I will start working on it as soon as I can. I'll also try to contact RoyC

About the AB switch I'll be needing a replacement cause what is left is just the plastic part. What kind of switch is it?

Unfortunately I'm in Argentina (south america)...far far away from the US, so I don't think any CSP member could help me this time. 

 Juan

[JKent]

Wow! I don't know if we have any members in SA. I visited your beautiful city a couple of years ago.

According to the schematic the switch is a standard DPDT (dual pole dual throw) toggle switch. Probably available in BA at an electronic parts store, hardware store or auto parts store. Something like this https://www.parts-express.com/dpdt-heavy-duty-toggle-switch-spade-connectors--060-452

[JKent]

Well, I feel a little foolish. My original reply was based on the assumption you were in the US. I just heard from RoyC and he said that it may be a lost cause. The cost of drivers and other parts being sent to Argentina could be prohibitive. He also mentioned that your woofer cones look odd. Whoever "worked" on those totally butchered them and it may not be practical to try to restore them. Sorry if I gave you false hope.

[Juan9568]

Uhh....yes, that was my first impression...If at least I had the drivers it would be a different thing....

Still...i won't fire up the barbecue yet...

Thanks Again!

[RoyC]

Juan,

The  AR-3a Improved was a short lived model sold during the transition from the AR-3a to the AR-11. Below is the only photo I have of an intact crossover, with some important connections buried in glue. Based on your photos and the missing drivers, your speakers would be expensive and difficult to restore.

Roy

[djcheung]

Here is one not very clear co of my 3a Improved.

[Robert_S]

On 6/19/2017 at 3:35 PM, JKent said:

Also look at this thread. John O'Hanlon (johnieo) knows a lot about this speaker. He mentions that the Improveds did not use the same tweeter as the original 3a. It's a ferrofluid cooled model, pictures A-22 or A-24 in the AR-3a restoration booklet. He also mentions that AR-10pi and AR-11 tweeters Are perfect replacements. Google "AR-3a Improved" and you will find more good info.

Hello,

Regarding John's comment on the AR-3a Improved tweeter, he acknowledged that he was mistaken in his belief that the tweeter used was the ferrofluid cooled version. It was, as evidenced to date, the same tweeter as used in the AR-3a.

For more on the subject of the AR-3a Improved, the topic/thread linked to above may prove useful.

Robert_S

[JKent]

1 hour ago, Robert_S said:

It was, as evidenced to date, the same tweeter as used in the AR-3a.

oooops. Sorry.

So I'll go back to suggesting the Hi-Vi.

[Juan9568]

4 hours ago, JKent said:

oooops. Sorry.

So I'll go back to suggesting the Hi-Vi.

Thanks for all this info!. I'm about to get rid of the woofer and cut the cabinets in pieces......As RoyC pointed out, this would be a difficult and expensive restoration..Unless, there  is some alternative Mid Range drivers that I could use...

The Hi-Vi tweeters are not that expensive ($18.80), do you know if there's something for the mids in that price range??

[Glitch]

Juan,

A full restoration might very well be expensive, but unless you have your heart set on originality, you have other options.  You already have the most expensive parts of a speaker with the woofers and cabinets.  You also already have the most expensive part of the crossovers, the inductors.  I don't know your budget, but there are many "modern" components that you could substitute for the missing pieces and have a nice set of speakers.  It might be worth asking the same questions in a DIY speaker building forum before you take a saw to the cabinets.

I've built several pairs of speakers based on old woofers and cabinets with Chinese made tweeters.  You can get very good value for your money with careful shopping.  For instance, digging around a "popular auction site" can yield you a set of dirt cheap foam surrounds from China.  The only drawbacks are that the shipping time is long and the woofers aren't original (but more original than the woofers being in a trash can).  Your could order the other parts you need from a discount speaker parts website.  Stick with non-polar electrolytic capacitors and low cost, highly rated (based on customer feedback) drivers.  You may be pleasantly surprised about how good a $15 tweeter can sound.  

For the cabinets, some wood filler and black paint can make most anything look presentable.  Pick a grill cloth that is in line with your taste, install this neatly, and nobody will ever know about the other choices you made or how expertly you did the other work.  

The hardest part of the speaker design, properly matching the cabinet size to the woofer characteristics, is already done for you.  Set the mid/woofer crossover value to something close to the original.  Set the mid/tweeter crossover value to something close to whatever the driver manufacturers recommends.

This project could be a lot of fun (if you like doing this kind of stuff).

Glitch

 

[Juan9568]

Hi, I'm still looking into this repair but I have 3 questions.

• What type of resistors do I need for the crossover? I know is 1 Ohm, 1.5 Ohm, 10 Ohm and 1 Ohm but what about the wattage?
• About the Hi-Vi tweeter replacement it is recommended that I use a .7mH Coil in parallel to the tweeter but what gauge should it be?
• Any clue on the midrange replacement?

I wanna get all the components right

Thanks!

[ar_pro]

Resistors are cheap. Go with a 25 watt-type if possible.

I believe Parts Express recommends an 18 gauge coil for use with the HiVi tweeter.

 

[RoyC]

Juan,

First of all, I disagree with an earlier post stating that properly matching the cabinet size to woofer characteristics is the "hardest part of the speaker design".  There is much more to it, but that isn't the point of this thread. Just know that replacing the tweeter and midrange drivers with something other than original drivers will not result in anything like the original speaker. The HiVi tweeter replacement was studied and tweaked to make it similar to the original tweeter with models utilizing variable level controls. The switches in your speakers are not versatile enough to work as well with these tweeters.  Adding aftermarket midrange drivers would require re-designing the crossover to have any hope of sounding like the original arrangement. The bottom line is you can make some modern drivers fit the unusually large AR cabinet holes resulting in fully functional speakers, but matching the original crossover details will not result in the original sound.

Btw, the coil used with the HiVi tweeter  is .05 to .07mH, not .7mH...big difference. I corresponded with Parts Express when I first came up with the HiVi arrangement suggesting that .07mh would be a good starting point. Since then I've found .05mh to work a bit better (and is more readily available)...and nothing larger than 18ga or 20ga is needed.

Unless used in the woofer circuit, 10 watt rated resistors (or higher) will work fine.

Roy

[Juan9568]

44 minutes ago, RoyC said:

Juan,

First of all, I disagree with an earlier post stating that properly matching the cabinet size to woofer characteristics is the "hardest part of the speaker design".  There is much more to it, but that isn't the point of this thread. Just know that replacing the tweeter and midrange drivers with something other than original drivers will not result in anything like the original speaker. The HiVi tweeter replacement was studied and tweaked to make it similar to the original tweeter with models utilizing variable level controls. The switches in your speakers are not versatile enough to work as well with these tweeters.  Adding aftermarket midrange drivers would require re-designing the crossover to have any hope of sounding like the original arrangement. The bottom line is you can make some modern drivers fit the unusually large AR cabinet holes resulting in fully functional speakers, but matching the original crossover details will not result in the original sound.

Btw, the coil used with the HiVi tweeter  is .05 to .07mH, not .7mH...big difference. I corresponded with Parts Express when I first came up with the HiVi arrangement suggesting that .07mh would be a good starting point. Since then I've found .05mh to work a bit better (and is more readily available)...and nothing larger than 18ga or 20ga is needed.

Unless used in the woofer circuit, 10 watt rated resistors (or higher) will work fine.

Roy

Yes I know I will never get the original sound, that's almost impossible but it doesn't bother me much as I never listened to these speakers when they where new....I was maybe 2 years old so I can't remember

What I do recall is that the woofers have a very deep and strong sounding bass, so I would like to take advantage of it and throw in some ok sounding Highs and Mids just to get these set of speakers working.

You're right about the coil, thats a huge difference!

So, 10 watt or more for the mids and highs and the one for the woofer should be??

 

[RoyC]

9 hours ago, Juan9568 said:

Yes I know I will never get the original sound, that's almost impossible but it doesn't bother me much as I never listened to these speakers when they where new....I was maybe 2 years old so I can't remember

What I do recall is that the woofers have a very deep and strong sounding bass, so I would like to take advantage of it and throw in some ok sounding Highs and Mids just to get these set of speakers working.

You're right about the coil, thats a huge difference!

So, 10 watt or more for the mids and highs and the one for the woofer should be??

 

25 watts or more...but, given what you have to work with and your present intentions, I would not use any resistors in the woofer circuit. In fact, you are moving so far away from the original design I suggest eliminating the entire "Improved" crossover. Very little of it (butchered or otherwise) will be of any practical use with new tweeters and mids.

I recommend using the AR-3a crossover as a starting point, which, among other things, could replace the entire switch/resistor arrangement with 8 ohm L-pads. This will simplify things and provide many more settings, There are even a few components you can salvage from your old crossovers. (Imo, the Improved was not an "improvement" over the original 3a to begin with.) This approach would provide a reasonable direction, and have a much greater chance of a satisfactory outcome.

As it stands, I'm not aware of any modern dome mid you can use in this project. If you don't substantially change the crossover points you would have to go with cone mid drivers...and with any new driver you will most likely have to modify the cabinet holes. You could save yourself lots of work and likely frustration by acquiring AR dome mids dating from the late 60's through the 80's. Though a bit costly, Ebay's "Vintage_AR" has a variety of them and ships internationally.

Roy

[JKent]

9 hours ago, RoyC said:

You could save yourself lots of work and likely frustration by acquiring AR dome mids dating from the late 60's through the 80's

Just be careful. AR2ax "mids" are actually tweeters and are not what you want. The 10pi or 11 are ideal, as I mentioned earlier, or other options as Roy mentioned. AR-91/92? Maybe you should check here or PM Roy before purchasing anything. 

9 hours ago, RoyC said:

I recommend using the AR-3a crossover as a starting point, which, among other things, could replace the entire switch/resistor arrangement with 8 ohm L-pads. This will simplify things and provide many more settings, There are even a few components you can salvage from your old crossovers.

Roy--What about building the simpler AR-3 crossover?

One more thing Juan: Are you sure those woofers are both good? If they're the raison d'être for this project you want to be sure they're good.

-Kent

[ra.ra]

Ambitious idea?....yes, perhaps, but some of the recent comments (like AR-91/92 drivers) here reminded me of this great thread. Perhaps a pair of Hi-Vi tweeters could be substituted in order to reduce the cost of new parts? I really loved this excellent project by ar_pro, although I would have been inclined to include some tone controls.   

 

[Glitch]

Roy:  Of course there "is much more to speaker design".  Perhaps, my statement would have been better stated as the woofer/cabinet matching as the hardest part of "speaker building" instead of "speaker design".  For many people, soldering together crossover components is much easier than building a suitable cabinet from scratch.  Starting with a well-designed and matched woofer combination goes a long way.  Combining this with a properly sealed cabinet and the right amount of fiberglass stuffing, and one would be pretty much guaranteed good bass response.  The mid/highs are trickier.  There are many ways to tackle this problem.  There are many modern, solid 3-way DIY designs that could be used as a starting point.  One could use the high/mid crossover design from DIY setup.  The low/mid crossover design from the AR could be used as a starting point.  This crossover frequency is designed for the woofers in question and has the added benefit to be at a low enough frequency where the crossover design is relatively forgiving.  It would be fairly easy to pick mids/tweeters that are more efficient that the original/missing AR parts.  The final speaker voicing for the mid/high could be dialed back using L-pads or adding resistors.

JKent:  You make a excellent point about verifying that the woofers are good.  It would be prudent to take this step regardless of whether the goal is a full restoration or a resto-mod.

Juan:  If you decide to go the resto-mod route, be sure to buy a sealed back midrange.  It might also be worth sending an email to the fine folks at Parts Express to see if they could make specific driver recommendations.  It sounds like you have reasonable expectations about what you will end up if you pursue the project.  I'm quite confident that whatever you do, you will end up with a set of speakers that sound much better than what you currently have.  

Anyone:  Can you comment on the chances for success of sourcing used, 50 year old AR drivers?  My experience with vintage parts is that it can be difficult to find two drivers that match.  It is ever harder to find two drivers that match AND are close to the original performance specifications.  From what I've read, some AR mids/tweeters are experiencing the ravages of time.  How much consideration should be given to this when planning a restoration?  

As a side comment:  I think that it is a great accomplishment to restore a pair of vintage speakers to their original aesthetics and performance.  This is not an easy thing to do.

 

[RoyC]

4 hours ago, JKent said:

Just be careful. AR2ax "mids" are actually tweeters and are not what you want. The 10pi or 11 are ideal, as I mentioned earlier, or other options as Roy mentioned. AR-91/92? Maybe you should check here or PM Roy before purchasing anything. 

Roy--What about building the simpler AR-3 crossover?

One more thing Juan: Are you sure those woofers are both good? If they're the raison d'être for this project you want to be sure they're good.

-Kent

Hi Kent,

I was careful to suggest AR dome mids. The 2ax mid is a cone mid. AR dome mids have held up very well, especially the back-wired versions manufactured after the mid 70's...the difference being that the magnet was screwed, as opposed to glued, in place. Juan would be better off with any generation of AR dome mid rather than any modern replacement. The crossover and interaction with his woofers is already known. Anything else is a crapshoot and will require crossover work.

The later AR-3 crossover could also be a worthy effort, and certainly a more reasonable starting point for the inexperienced. Even though the later woofer is not as well suited to the 3 crossover, the results would likely be better than just slapping a couple of modern tweeters and mids into the cabinets and hoping for the best.

Glitch...I think I know what you are saying. My point, however, is the existing crossovers in Juan's speakers, are simply not worth the effort of restoring if different drivers are used. The project ultimately becomes one of creating a new speaker system around the woofers, which requires at least some knowledge of how crossovers work. This is why someone can replace existing drivers with costly replacement drivers and end up with mediocre sounding speakers, and someone who knows their way around crossovers can use very inexpensive drivers and achieve a much better outcome. My opinion is that Juan needs a better starting point than just the AR woofer/cabinet combo.

Roy

[genek]

Since these cabinets appear to be vinyl covered and not wood veneer, there's not much that can be done as far as "restoring asthetics." If these fell into my hands, I'd probably paint the cabinets black, seal up the mid and tweeter ports and replace the crossovers with a good quality subwoofer plate amp. Then start shopping for a pair of later small AR models with dome tweeters (TSW-110/210 or 208/218V)