AR 11 Question

[Guest witnerd]

I recently had the good fortune of buying a pair of AR 11's that I am cleaning up. They have the foam grilles, which show a little disintegration, but are overall very nice!

I have a couple of questions. The first has to do with the logo plates. I have the second version with the black rectangles with silver lettering. On the pair I bought they sit a bit away from the wood and can be rotated. Is that how they should be? If not, how should they be?

My other question has to do with the woofers. They look beautiful, so I'm guessing they were either replaced or refoamed. Do they look as they should?

thanks!!

[KlausDK]

I have a couple of questions. The first has to do with the logo plates. I have the second version with the black rectangles with silver lettering. On the pair I bought they sit a bit away from the wood and can be rotated. Is that how they should be? If not, how should they be?

My other question has to do with the woofers. They look beautiful, so I'm guessing they were either replaced or refoamed. Do they look as they should?

Hi

The logo plate arrangement sounds OK to me, I have both versions of the ASR-11, and the aluminium/black ones is on a pin rather than a screw and mounted in a white plastic holder (bushing).

The woofers looks like later replacements (Tonegan), not as good as the original but much better than the replacement woofer you can buy today.

BRgds Klaus

[Guest witnerd]

Many thanks Klaus - I am not familiar with Tonegan woofers and would be interested in comments from you or anyone else regarding them. Thanks, Michael

[KlausDK]

Hi Michael

Take a look at this thread called " Evolution of and Replacements for the AR 11/12" Woofer", and you will be a lot wiser on the AR 12" woofer, pay special attention to post #7 by Tom Tyson, where you get a good overview.

http://www.classicspeakerpages.net/IP.Boar...?showtopic=1147

BRgds Klaus

[Guest witnerd]

Hi Michael

Take a look at this thread called " Evolution of and Replacements for the AR 11/12" Woofer", and you will be a lot wiser on the AR 12" woofer, pay special attention to post #7 by Tom Tyson, where you get a good overview.

http://www.classicspeakerpages.net/IP.Boar...?showtopic=1147

BRgds Klaus

Thanks again Klaus! Tonight I looked inside and was able to confirm those are Tonegan woofers (#12100032), as you said, although having read that thread, I am too much of a beginner to understand whether "The Tonegen (#1210003-2A from 1994) seems to have the stiffest suspension of all and of course no basket screen" is good, bad or indifferent....

I also took a shot of the caps, etc.. I imagine those are all original, but am hoping you or someone on this forum confirm this. Thanks again for your help! Michael

[KlausDK]

I also took a shot of the caps, etc.. I imagine those are all original, but am hoping you or someone on this forum confirm this.

Hi Michael

I think this quote from Tom Tyson's post sums it up pretty well:

"The Tonegen flat-side woofer, built as a service-replacement item in the early 90s, is also very close in every respect to the original woofer, and is interchangeable in all AR speakers using the flat-side 12-inch woofer. It has a slightly higher resonance due to its relatively low compliance, but the trade off is significantly higher power-handling capability. It is not quite as “warm” sounding as the earlier speakers, but works well as a replacement woofer. "

Which means that it is a pretty good replacement, but if you want the "correct" AR sound, you should work on getting two original woofers, but it is no panic.

The capacitors look all original to me, and therefore, you should use the opportunity to get new installed before you use the speakers, they can be way off their original values. Pay special attention to the quality of the 10 and the 40 uF caps, since they have the greatest influence on the sound.

BRgds Klaus

[Diamonds&Rust]

Thanks again Klaus! Tonight I looked inside and was able to confirm those are Tonegan woofers (#12100032), as you said, although having read that thread, I am too much of a beginner to understand whether "The Tonegen (#1210003-2A from 1994) seems to have the stiffest suspension of all and of course no basket screen" is good, bad or indifferent....

It's not really all that subjective or that "loose," in my experience. The original woofer designed specifically for the AR-10pi / AR-11 is the one you want if you have a choice. The later woofer, the same as the AR-9, was not really intended for a cabinet as small as a 3a / LST / 10pi / 11. The original free-air resonance isn't the only issue, but it was lower in the "correct" driver for that speaker. Been there, done that, worked "o.k." if "o.k." is what you're after. If you want it to sound like it was supposed to sound - get an older driver.

Would I throw the woofers you have in the garbage? No. Someone with an AR9 missing a woofer might benefit from them. If you can pick-up a pair of the original foam-roll woofers for a 3a / LST you will hear a difference in both the lower midrange and absolute bass extension. The *best* driver is the original, early 10pi / 11 driver. It's slightly different than the 3a woofer and different than the later woofer used in the 10pi / 11. Late production 3as probably used that woofer, too, since AR didn't seem to keep different iterations of the 12" woofer in stock for different speaker systems.

I don't know if they were cutting costs, or cutting warranty replacements, or what, but the system was originally designed with a different tweeter and different woofer - the midrange changed a little, too, but I can't hear a difference between one generation of midrange and another. The difference in the tweeters is audible, but perhaps not earthshaking. The woofer is another story. If you can get early woofers, and you want your 11s to sound their best - do it.

I also took a shot of the caps, etc.. I imagine those are all original, but am hoping you or someone on this forum confirm this. Thanks again for your help! Michael

Those capacitors *have* to go. They are the originals. They were manufactured by Callins. We've measured enough of them to know that they are *highly* suspect. In fact, it would be miraculous if they were still good. There are older capacitors that hold-up better, there are newer that hold-up better, but those you have --- well, they just have to go. Sooner would be better than later.

As to what to replace them with? I'm not getting involved in that discussion again - but some find a poly cap with a small 0.1 to 0.3 Ohm resistor in series produces a good result - some find they like the poly caps without the resistor - some will say replace them with modern non-polar electrolytics - some like the expensive caps - some like the cheap - some like mylar - some... You know what I think? I think getting new capacitors in there is the most important thing - and the rest of it is arguable.

[Guest witnerd]

It's not really all that subjective or that "loose," in my experience. The original woofer designed specifically for the AR-10pi / AR-11 is the one you want if you have a choice. The later woofer, the same as the AR-9, was not really intended for a cabinet as small as a 3a / LST / 10pi / 11. The original free-air resonance isn't the only issue, but it was lower in the "correct" driver for that speaker. Been there, done that, worked "o.k." if "o.k." is what you're after. If you want it to sound like it was supposed to sound - get an older driver.

Would I throw the woofers you have in the garbage? No. Someone with an AR9 missing a woofer might benefit from them. If you can pick-up a pair of the original foam-roll woofers for a 3a / LST you will hear a difference in both the lower midrange and absolute bass extension. The *best* driver is the original, early 10pi / 11 driver. It's slightly different than the 3a woofer and different than the later woofer used in the 10pi / 11. Late production 3as probably used that woofer, too, since AR didn't seem to keep different iterations of the 12" woofer in stock for different speaker systems.

I don't know if they were cutting costs, or cutting warranty replacements, or what, but the system was originally designed with a different tweeter and different woofer - the midrange changed a little, too, but I can't hear a difference between one generation of midrange and another. The difference in the tweeters is audible, but perhaps not earthshaking. The woofer is another story. If you can get early woofers, and you want your 11s to sound their best - do it.

Those capacitors *have* to go. They are the originals. They were manufactured by Callins. We've measured enough of them to know that they are *highly* suspect. In fact, it would be miraculous if they were still good. There are older capacitors that hold-up better, there are newer that hold-up better, but those you have --- well, they just have to go. Sooner would be better than later.

As to what to replace them with? I'm not getting involved in that discussion again - but some find a poly cap with a small 0.1 to 0.3 Ohm resistor in series produces a good result - some find they like the poly caps without the resistor - some will say replace them with modern non-polar electrolytics - some like the expensive caps - some like the cheap - some like mylar - some... You know what I think? I think getting new capacitors in there is the most important thing - and the rest of it is arguable.

Thanks for your informative response!

[Guest Jeffy]

Hello,

A newbie here. I have also just acquired a set of AR-11b through a death in the family, RIP.

The grilles and woofers I believe are original... and likely are the caps. The grilles look good. The woofers need replacement surrounds; they have been ordered from Speakerworks.com.

For the caps... I'm not even really sure where to start. I know replacements will be needed, but what about ESR? How do you know what resistor value to put with the caps?

Attached are some pictures of the speakers.

Thanks,

Jeff

[Diamonds&Rust]

Good looking pair of speakers, Jeff. I'm sure you'll enjoy them for years.

I know replacements will be needed, but what about ESR? How do you know what resistor value to put with the caps?

I can’t tell you if there is a lot or a little or *nothing* going-on with ESR and capacitors.

We can tell you that if you replace the capacitors with polypropylene caps your speakers are going to “brighten.” But none of us can tell you by how much, or in which frequencies exactly, or anything else definitive.

ESR isn’t the only issue. Capacitance isn’t the only issue, either. In fact, we haven’t scientifically isolated an issue, yet. ESR is one of those “standard specs” of a capacitor and so it, and C (capacitance), are easy conversation starters. Frankly, I’ll tell you that ESR is not as simple a concept as I thought. If it were resistance (real, broadband, resistance), a capacitor would have a simple “resistance” and we could entirely avoid the word “equivalent.” That’s an esoteric conversation you don’t want to get started with.

Common sense tells you (or me, or anyone who thinks about it a second), that if ESR were “resistance” per se, 0.1 Ohms of resistance would be inaudible. Your midrange drivers may have a DC resistance differential greater than 0.1 Ohms between them. It should take about .375 Ohms across a your tweeter to make a 3/4db change in output. Theoretically, you can’t hear 3/4db, but most skeptics to the audibility of different components insist that levels be matched to 1/10db or the tests are declared invalid. So, which is it? I can’t say. I don’t even care.

About the only useful thing I can tell you about the ESR issue is that it is counter-intuitive. In the old capacitors, the *physically smaller* capacitors we have measured generally have a higher ESR than the larger. That makes sense for reasons I won’t go into here. 0.1 on the big ones, 0.3 on the small ones should get you in the ballpark.

Want your mind blown? How about if I were to tell you that some clearly, clearly, bad capacitors with all sorts of nasty issues have ESR numbers so low you’d think they were brand new audiophile models?

Having said that, you need to understand that electrolytic capacitors start changing / failing, as soon as they are made. (You don’t have to take my word for this - look at the expected life, expressed in thousands of hours, on any electrolytic capacitor’s data sheet.) Some fail faster than others and there are many different ways they can fail and the different ways they fail show-up as increases / decreases in various standard capacitor measurements - but a measurement of “x” in one cap may be showing a failure while the exact same “x” in another capacitor of the same “C” might be exactly on spec. The “x” doesn’t denote failure. The “change in x” may point to a failure that has nothing to do with “x” itself.

So what to use, what to use? We’re not “there” yet. We can’t explain this, yet, and if any capacitor manufacturers have a clue, they aren’t telling. All sorts of exotic claims are made, but nobody provides any numbers to back-up their claims, hence the whole assumption that cap differences don’t exist and manufacturers of “super exotic capacitors” are duping us into lining their pockets.

I’m not convinced of that, yet. I can understand why a manufacturer that believes it knows why its capacitors are “superior” would not be quick to publish “why.” I assume that once the issue is defined, anyone could turn a $0.50 capacitor into a $35 capacitor.

On the other hand... it sure looks like some of them sell their wares at “Suckers-R-Us.” I wouldn’t pay more for a pound of sugar based on nothing more than the assurance of the seller that this pound in the yellow bag is superior to that pound in the blue bag “because it tastes better.” I’d want to know what is different. Capacitor manufacturers do little but make assertions about “sound” and superiority. But notice, none of them are asserting a superior ESR number. Why? Because modern poly caps (all of them) have ESR so low that it might as well be zero.

But guess what? Some old bad capacitors have measured ESR < 0.02 Ohms! That’s 2/100ths of one Ohm for the decimally impaired. You can hear that? “O.k., SuperEar, tell me what else you can hear. Maybe someone in Sweden turning-on their ASKO dishwasher, for instance?”

Bottom-lining it, once again, *some* people find adding .1 to .3 Ohms to a polypropylene capacitor achieves a pleasant result. *Some* don’t find the resistance necessary. *Some* find they like expensive caps, *some* don’t, and still others swear they *can’t* hear a difference between their old electrolytic capacitors which tested “good” and new ones of any sort. *Some* find poly caps offensive unless attenuated with resistors. Since none of us has measured data which can explain this, nobody can tell you, for certain, what to do with your speaker and your capacitors.

Some sophisticated A/B/X tests have shown that you can’t hear a difference in capacitors in electronics and that was extrapolated into crossovers, too. (Which is idiocy, or deafness, or a limitation of the electronics or source. Even those of us who seriously doubt capacitor manufacturer claims have to admit there is a difference, even if it IS 0.01 Ohms of ESR - madness I tell you, madness!)

But let’s say the “too bright” crowd is right. Put a resistor on the cap and that problem goes away. If the “you don’t need a resistor” crowd is right - and the resistor makes no difference - then by all means, add the resistor since it doesn’t make a difference. If the “I can’t hear any difference between the old caps and new polys” crowd is right, add the resistor because it won’t make but a 3/4db difference anyway and your furniture is going to change things that much. If the “polys brightened my system and I like it” crowd is right, add the resistors and you’ll never know what brightness you are missing so it won’t matter and it’ll sound great to you - because it'll get better, brightness aside. If the “You are an idiot, Bret. The ESR of 0.02 Ohms was an important crossover design element,” are right (uh-huh, yeah, right) then add .1 Ohms and be done with it. You can’t hear either value across the woofer, anyhow.

In other words, putting 0.3 Ohms on the tweeter 0.1-0.3 Ohms on the midrange, and 0.1 Ohms on the woofer is o.k. no matter what’s going on in reality.

The ULTIMATE reality is that we are restoring speakers, some of which are almost 50 years old. Any solution is okay EXCEPT leaving a bad cap in the speaker.

Hope that helps you avoid an ulcer.

[Diamonds&Rust]

Hello,

A newbie here. I have also just acquired a set of AR-11b through a death in the family, RIP.

The grilles and woofers I believe are original... and likely are the caps. The grilles look good. The woofers need replacement surrounds; they have been ordered from Speakerworks.com.

For the caps... I'm not even really sure where to start. I know replacements will be needed, but what about ESR? How do you know what resistor value to put with the caps?

Attached are some pictures of the speakers.

Thanks,

Jeff

Jeff,

I take back everything I said. Everything. Ever.

Here we have the final, clinching proof of what makes capacitors sound different and, as you will read, why ONE capacitor manufacturer above all others has the BEST sounding capacitors of all time. A statistically non-significant, sometimes non-majority, has said so.

http://www.madisound.com/manufacturers/claritycap/mr.php

That link was sent to me by a forum member who shall remain nameless to protect the innocent; but if he weren't nameless his name would be Roy.

Read the white paper, critically.

There may be something to this, but I can't tell from what they publish. Certainly their listening tests were... fairly un-impressively conclusive.

I suspect I won't be taking the plunge to do a $2,000 listening test on any of my AR speakers.

[Mexicomike]

I think I'll dust off the perpetual motion machine I built a few years ago. I'll bet those Clarity Cap guys could sell a bunch of them and I could afford to buy the Brooklyn Bridge. The owner, a former Nigerian cabinet minister, sent me an email offering to sell it and the price is too good to pass up!

[Guest Jeffy]

Wow! Diamonds&Rust, that was quite the response! It sounds like you've got a pretty good handle on what works in the 'real world' vs. the 'theoretical world' for these crossovers.

I think I'll replace the old caps with some Dayton caps from partsexpress... unless there are any big objections?

[Guest Jeffy]

oh wait, I meant to say I'll get those clarity caps unless there are any big objections

[r_laski]

>>I think I'll replace the old caps with some Dayton caps from partsexpress... unless there are any big objections?<<

Not an objection, but a warning and a recommendation.

I tried using Dayton caps in an AR-90 crossover. I did not like the results at all. To me, they sounded no better than the out of spec original caps when I conducted a subjective listening test of a Dayton recapped AR-90 against an originally capped AR-90.

I replaced the Daytons with Solens and North Creek (no longer available) caps and the difference was remarkable. I posted more information on this in this forum way back when I did this.

I recommend you buy the Dayton caps if thats what you want to use and recap only one of your AR-11s. Then do your own listening tests comparing the Dayton recapped AR-11 against the originally capped AR-11.

If you like what you hear, stick with the Dayton caps. If not, you can return any unused Daytons to Parts Express and try something else. Maybe some of their Solens.

The Daytons are relatively small and you might be able to mount them where the original caps are. Solens and others are much bigger and you may have to rearrange things on the crossover board to fit them in.

[r_laski]

I received a request from a forum member for some pictures of AR-11 crossovers I rebuilt that are no longer available in my previous postings since the overhaul of the forum.

I've attached them here to share with all forum members. Hope they help anyone recapping their AR-11.

Rebuilt AR-11 Single board crossover.

Original two-board AR-11 crossover.

This is the only picture I could still find for this crossover rebuild. The woofer caps are not shown. They are located at the front of the bottom board.

This one's for you Klaus

Rich

[Diamonds&Rust]

It sounds like you've got a pretty good handle on what works in the 'real world' vs. the 'theoretical world' for these crossovers.

I'm sorry I gave you that impression. I've only tried five or six capacitor iterations, and I did come-up with an absolute favorite of my own. Most of what I know I've learned from the people on this forum who I have come to respect as perfectly reliable witnesses. I'm perfectly willing to admit that their experiences are just as valuable, and sometimes more experienced, than my own.

I have just reported a quasi-marriage of all of the collective wisdom around here. Had I been basing my response solely on my experience, my advice would have been slightly different.

I think I'll replace the old caps with some Dayton caps from partsexpress... unless there are any big objections?

Listen carefully to what Rich is telling you. I have no experience whatsoever with Dayton capacitors, but Rich is one of the several people whose words to take very seriously. Not only does he have an opinion, but it isn't one of those blind opinions based on what he thinks he knows. He's been there / done that, several times. In fact, he went quite a bit further in his admittedly subjective tests than he tells. It was time consuming and no small amount of trouble.

Rich has much experience with the AR-11.

You may as well benefit from it.

Bret