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No...the notches were already stamped in place before assembly. The white dot setting is supposed to be 6 ohms (series) for the AR-5 mid, and the tweeter dot is less. The result is the pointers of the mid and tweeter knobs are in different places when set to maximum if they were installed properly.

Roy

That would make sense. They used a die-punch to make the two holes and the notches simultaneously. At least one pot had a detent setting made by deforming one coil of the resistor wire. It wasn't well defined and I didn't pay much attention to it. In the unlikely event I ever take them out again I will take a closer look and measure the resistance at the detent and verify if there is a detent on the other pot -- otherwise it is just a defect on the one coil.

I went back and looked at the damaged wire lead to the mid -- seems I over-dramatized it a bit as only five strands were broken out of 16; however, five more than should have been. It was not a performance issue at any rate as the leads on the drivers are much smaller.

I came across a solution on another forum for the back labels should I decide to remove them -- which was to take a hi-res photo and print out a new label.

A Euro-style pair of AR-5s slipped by me here on a local listing for $100 the other day which is ten times more than I paid for this pair!.... As us old-timers slip away I'm sure there will be more and more of these classic speakers showing up for those lucky enough to be in the right place at the right time ;)

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Nice job on the re-cap. So what do they sound like with the mylar/polyester caps? I don't think I saw any comments on that.

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Nice job on the re-cap. So what do they sound like with the mylar/polyester caps? I don't think I saw any comments on that.

Hmmmm, sound great to me, clean, clear, tight, but, would need to A/B them in a controlled environment to be any more specific. :unsure:

I have a friend that wants to hear them so I am planning to pack them along with the Ohms over to his place for a listen.

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Excellent thread Roger, thanx! Great pics, work and input from others. I am in the process of working out a deal on a set of these (oiled walnut) and will find a good bit of this useful.

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This may be a very amusing time to re-open a can of worms that I started back in Oct 2002, when this Forum's readership was considerably different than it is today. Many of the old members no longer seem to frequent these pages, and we have many new members.

That said, I'll just toss this out and wait for the reactions:

Posted 16 October 2002 - 08:58 PM

Suffice to say, the original AR speakers certainly elicited more than their share of controversial opinions. Many consumers and reviewers considered them to represent the very height of engineering excellence, accuracy, and uncolored, natural sound. But there was also the “anti-AR” crowd, who thought the speakers were dull, and lacking sparkle. This group would concede AR’s outstanding bass, but criticized them for their low efficiency and what they felt was a depressed high end.

The AR-3a has always been the favorite target of the anti-AR faction. “Too much bass,” “The tweeter level can’t be brought up to match the woofer,” “It needs a big, expensive amp to drive it,” etc. This criticism reached its public zenith with the infamous Consumer Reports review. (It’s fascinating, however, to note AR’s understated and classy response to this review, in sharp contrast to another well-known Massachusetts speaker manufacturer’s highly publicized, wildly histrionic reaction to the negative review of their “revolutionary” speaker.)

My feeling is that most of the criticism of the 3a came about because of professional envy, and the natural tendency of human nature to cast aspersions at the acknowledged leader in an effort to make up for one’s own shortcomings. The AR-3 and 3a speakers, from 1958-1972, were simply the industry performance leaders in virtually every objective, measurable, quantifiable basis of comparison that existed.

Yet there is an undercurrent of grudging favorable sentiment among the naysayers towards the AR-5. I have noted this recurring theme in the 35 years I’ve been following AR’s product development and marketing activities. Many of the same industry luminaries who have expressed derisive comments to me about the 3a have also said such things as “…but the 5 was actually a very good-sounding speaker. Better overall balance. The tweeter is not overwhelmed by the woofer the way it is in the 3a.” I have heard this many times from many people over the years. Even High Fidelity Magazine’s review of the 5 intimated a similar point of view: “…sometimes sounded tighter…more ‘immediate’ than the 3a…”

I’m curious if any other Forum members, especially the, ah-hem, “veteran” members, have experienced similar reaction to the AR-5 from non-AR aficionados.

BTW, the “woofer level” relative to the tweeter was not any higher in the 3a than it was in the 5, despite what critics might have said. The 3a’s bass extension was considerably deeper than the 5’s and the psycho-acoustic effects of deep bass on perceived midrange and high-frequency clarity come into play when comparing the two speakers. But that’s an entirely different subject…

Steve F.

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Well, I'll start by saying I have not heard either the 3, 3a or 5. However, if you like it play it - doesn't matter what others think. If you play it don't stop listening to other speakers as you may find something you like better.

I do have a late model of that other 'revolutionary' speaker (after trading in my series II). The first 2 models had a better sound than the baffled models. I'm not sure the effort to gain more treble was worth the end results.

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My feeling is that most of the criticism of the 3a came about because of professional envy, and the natural tendency of human nature to cast aspersions at the acknowledged leader in an effort to make up for one’s own shortcomings. The AR-3 and 3a speakers, from 1958-1972, were simply the industry performance leaders in virtually every objective, measurable, quantifiable basis of comparison that existed.

Good sound reproduction is very subjective issue. Speakers like Quad ESL-57 and Spendor BC1 were better speakers than AR3a in critical mid range, but they had limited output capability. Dual concentric models from marques like Altec and Tannoy may be colored, but point source design provided more focused soundstage . Their output capability is higher and distortion is much lower... but cabinet size can not be considered to be modest.

Coloration is also very subjective issue. BBC style low coloration cabinet provides low coloration level in critical mid range, but can sound little shy in LF. I auditioned couple of years ago current Spendor SP100R model and I was quite impressed by quality of reproduction... but SP100 did not deliver similar dynamic sound of drum set that my 1985 Tannoy LRM:s do. SP100 cab is slightly bigger, LF extension of SP100 is considerably better and both models do use 12" woofer. I think that SP100 is better speaker overall... but if you like to listen Gene Krupa and Ginger Baker? I think that lack of dynamics and lack of articulation is also one sort of coloration.

Reviews and consumer reports can also be biased. How you read and make your own conclusions from reports is also subjective issue. It was mystery to me how there were so many troubles with our Jaguar X- and S-types, even they scored very well in J.D. Power surveys. Maybe we got two cars made on Friday the 13th.

Reduced HF level of AR original models was not necessarily handicap. Reduced HF might have reduced ill effects of tracking distortion and problems in early solid state amplifier design. If you listen amplifier like H/K Citation 12, which was very good design of early 70`s, you may find it pretty good in most respect. But... HF reproduction is something that might sound better slightly attenuated. It has puzzled me, why power handling issue of AR tweeter was not sorted with 2nd order hi pass filter before arrival of 11 and 3aImproved models.

So... it seems to me that success of AR3/AR3a models, as well as other AR original modes, has something to do with stereo. Two huge cabinets were too much for wife of average hifi nut. AR engineering was solid, even some better designs did exist. Huge manufacturing quantities and good advertising made it possible to make reasonably sized high quality products, that buyers could afford.

I have now AR2ax, AR3aImproved and AR5 models from mid 70`s to be refurbished. I do not know if they are ready for comparison within 2 months or 1 year, but there is no hurry. I do know that this comparison is difficult. Caps and pots can be replaced or repaired, but 40 years old drive units are not performing as they used in mid 70´s. Cab seams can be be air tight, but it is difficult to tell how firmly panels are bonded to each other. So... comparison can not reproduce how things were in mid 70´s, but it is fun anyway.

Best Regards

Kimmo

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...Good sound reproduction is very subjective issue. Speakers like Quad ESL-57 and Spendor BC1 were better speakers than AR3a in critical mid range, but they had limited output capability....

Best Regards

Kimmo

>"Good sound reproduction is very subjective issue. Speakers like Quad ESL-57 and Spendor BC1 were better speakers than AR3a in critical mid range, but they had limited output capability. Dual concentric models from marques like Altec and Tannoy may be colored, but point source design provided more focused soundstage . Their output capability is higher and distortion is much lower... but cabinet size can not be considered to be modest."

Kimmo,

Good sound reproduction shouldn't necessarily be "very subjective," as though that is the major or perhaps sole criteria for quality, but it should be the outcome of objective design goals and implementation of good engineering accompanied by subjective evaluation. Coincidentally, clean, accurate sound reproduction usually does sound "good," making it subjective, but that is not the goal of high-fidelity sound reproduction, just to make it sound "good."

The AR-3 was a perfect example of this characteristic: it measured superbly well, but it also sounded good. AR didn't begin selling this speaker because Ed Villchur listened to it and decided that it was a "good-sounding" speaker. It wasn't "voiced," as were so many other speakers of the day. Its sound wasn't spectacular or "impressive," but the AR-3 was proven to be highly capable and accurate, validated, subjectively, through AR's many Live-versus-Recorded Concerts in the 1960s (which, though criticized, have never been duplicated before or since with such success). Therefore, the AR-3 was able to subjectively mimic the sound of live instruments, but the quality of the AR-3 reproduction was grounded in the laboratory and anechoic chamber with objective testing and validation long before someone came along and said the sound was subjectively "good."

Neither the ESL-57 or (especially) the Spendor BC1 were better speakers than the AR-3a in the midrange. That is some sort of emotional sentiment not based in fact. This implies that they were flatter, smoother with less distortion, and this isn't true. It's true that the spectral balance of the AR-3a midrange midrange was reduced somewhat with respect to the woofer's output, and this made the speaker initially sound heavy (a change in the woofer crossover circuit around 1969 improved this), but the reproduction throughout the designated midrange passband from 575 Hz through 5kHz was extremely flat and smooth, ±2dB or better, on axis (see attachment). The driver did not have frequency-response issues, and that dome driver had very low distortion. It also had wider dispersion than either of the two speakers you mentioned. I would compare the measured response of the AR-3a throughout the midrange to either of those speakers; I know the ESL-57 is a very flat speaker in this regard, but it isn't better than the AR-3a's midrange driver (although the overall midrange balance of the ESL might be flatter).

>"Coloration is also very subjective issue. BBC style low coloration cabinet provides low coloration level in critical mid range, but can sound little shy in LF. I auditioned couple of years ago current Spendor SP100R model and I was quite impressed by quality of reproduction... but SP100 did not deliver similar dynamic sound of drum set that my 1985 Tannoy LRM:s do. SP100 cab is slightly bigger, LF extension of SP100 is considerably better and both models do use 12" woofer. I think that SP100 is better speaker overall... but if you like to listen Gene Krupa and Ginger Baker? I think that lack of dynamics and lack of articulation is also one sort of coloration."

No, coloration is a form of distortion, and there is no subjective qualification to it. Yes, high coloration is subjectively unpleasant, but coloration can be quantified through proper measurement techniques, and it is certainly audible. But there is no such thing as good coloration and bad coloration. The lack of "dynamics" or the lack of "articulation" are the result of bandwidth and power-handling limitations, not a form of coloration.

>"Reviews and consumer reports can also be biased. How you read and make your own conclusions from reports is also subjective issue. It was mystery to me how there were so many troubles with our Jaguar X- and S-types, even they scored very well in J.D. Power surveys. Maybe we got two cars made on Friday the 13th."

Most likely, Consumer Reports dinged the Jaguars because of reliability or durability issues. The Frequency-of-Repair results on this brand—despite the car's excellent reputation for engineering and quality—have been universally below par, and CU won't recommend a vehicle with poor reliability records. JD Power and Associates is a paid service to manufacturers—and they do a rigorous testing, but they won't say anything bad—whereas CU takes no money from any manufacturer. Therefore, JD Power is more likely to give a company decent marks, regardless, much like audio magazines used to give decent reviews to some products that weren't particularly stellar, mainly because of ad revenue from the manufacturers.

>"Reduced HF level of AR original models was not necessarily handicap. Reduced HF might have reduced ill effects of tracking distortion and problems in early solid state amplifier design. If you listen amplifier like H/K Citation 12, which was very good design of early 70`s, you may find it pretty good in most respect. But... HF reproduction is something that might sound better slightly attenuated. It has puzzled me, why power handling issue of AR tweeter was not sorted with 2nd order hi pass filter before arrival of 11 and 3aImproved models."

The AR-3a's reduced high-frequency levels (with respect to the woofer and midrange output) was not intentional, but the natural outcome of drivers with lower sensitivity. The hard-dome tweeters almost universally have lower sensitivity than soft-dome equivalents, but the benefit is better dispersion. Compare, for example, the off-axis output of the AR-3a ¾-inch hard-dome tweeter to that of the newer AR-11 ¾-inch soft-dome tweeter. The AR-3a has broader dispersion, yet the AR-11 has 3-5-dB greater sensitivity throughout the operating range. It's a simple tradeoff: AR at the time chose to go with broader dispersion rather than higher sensitivity. One reason this was justified was that the spectral balance in a concert hall shows high frequencies broadly sloping downward, the higher in frequency you go, relative to the low- and mid-frequency balance. A rolled-off treble also reduced unpleasant LP surface noise during the day, so it was an added benefit for that as well.

>So... it seems to me that success of AR3/AR3a models, as well as other AR original modes, has something to do with stereo. Two huge cabinets were too much for wife of average hifi nut. AR engineering was solid, even some better designs did exist. Huge manufacturing quantities and good advertising made it possible to make reasonably sized high quality products, that buyers could afford.

No, the success of the AR-3 and the AR-3a models was not because they were small and had something to do with stereo; the success of AR loudspeakers was based on the quality and accuracy of reproduction and the ensuing reputation of the company, reviews and value. Stereo's presence in the late 1950s did make AR speakers much more popular, of course, in that very few people wanted to have large, refrigerator-sized loudspeakers flanking their living rooms. To my knowledge, there were no large loudspeakers being produced during the 1950s and 1960s that were equal in quality to the AR-3 (and later the AR-3a). None. By 1956, the AR-1 had put a huge "hurt" on the behemoth Klipschorn, Hartsfield, Patrician and other large horn-type speakers, and by the late 1950s, the AR-1—used in conjunction with JansZen 130 electrostatic tweeter—nullified the significance of the huge infinite-baffle Bozak B-310 Concert Grand. Arthur JansZen even chose the AR-1 over a 4-woofer Bozak for his reference system to promote his tweeter, showing that the single-woofer AR-1 had more potent, lower-distortion bass than even the B-310 (thought not louder). So, by the mid-1960s, AR's loudspeakers were dominating the landscape, and by 1966 AR had attained a market share of more than 32% of the domestic loudspeaker market. This was not because of "stereo," but it was because AR's speakers were superior in sound-reproduction quality and had established a reputation for this quality around the world.

—Tom Tyson

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With regard to Steve's post about the AR-5, I continue to notice something I posted awhile back. Even though it has the same sonic character as its siblings of the day, it is clearly less sensitive than all of them....regardless of what the "published specs" say. Between my own work and the assistance provided to Larry/"Vintage AR", I have had many opportunities to compare them, and I stand by my opinion that this did not help the plight of the AR-5 in the typical showroom. Further, in my opinion, if the mid control is turned to max it loses some of its charm. It should be noted that the 5's mid's white dot "normal" setting is considerably more attenuated than the 3a's. Of course, this has an effect on sensivity specs.

With that said, I very much like the sound of the AR-5, and can identify the difference in midrange character some people may prefer vs the 3a. If I were asked to recommend a model for acoustic and vocal reproduction at low to moderate volume levels, I would not hesitate to recommend the 5. If bass heavy music, pipe organs, or high volume levels are in the mix, the 3a is a better bet, imo.

Roy

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With regard to Steve's post about the AR-5, I continue to notice something I posted awhile back. Even though it has the same sonic character as its siblings of the day, it is clearly less sensitive than all of them....regardless of what the "published specs" say. Between my own work and the assistance provided to Larry/"Vintage AR", I have had many opportunities to compare them, and I stand by my opinion that this did not help the plight of the AR-5 in the typical showroom. Further, in my opinion, if the mid control is turned to max it loses some of its charm. It should be noted that the 5's mid's white dot "normal" setting is considerably more attenuated than the 3a's. Of course, this has an effect on sensivity specs.

With that said, I very much like the sound of the AR-5, and can identify the difference in midrange character some people may prefer vs the 3a. If I were asked to recommend a model for acoustic and vocal reproduction at low to moderate volume levels, I would not hesitate to recommend the 5. If bass heavy music, pipe organs, or high volume levels are in the mix, the 3a is a better bet, imo.

Roy

Thanks, Tom T, Steve F, and Roy C for your experience, insights and educated opinions. They pretty much follow mine. I don't remember if I auditioned the AR-3s back in the 70s when I bought my original AR-5s but I remember being attracted to the gossamer highs of the ESS Heils and somewhat overwhelmed by four JBL 100s on a Marantz 2270 at 3/4 volume playing Deep Purple's "Smoke on the Water" live version in a small room. I guess I bought the 5s because they matched my personality -- accurate, reserved, conservative, somewhat stuffy, requiring lots of power and preferring not to be over driven!

While it seems AR didn't adapt well to the changing marketplace, there is no questioning Villchur's inspiration -- the magic is still there after all these years. I wasn't aware of the history when I bought the speakers but I keep finding these gems on the web: http://www.stereophile.com/interviews/105villchur/

Lots of "boom squawkers" have come and gone but I wouldn't hesitate to buy an old pair of AR-3s if the opportunity presents itself or another pair of 5s, or any of the classic ARs.

Roger

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Just wanted to say that I've really enjoyed following this thread for several reasons, not least of which is that it originated as the first post by a new member, from a deep western state, concerning his renewed interest in the oft-overlooked AR-5 product.



Also, this discussion includes many excellent succinct statements, including these three:



* post 57, from Kimmo: ".........but it is fun anyway."


* post 59, from Roy: "....I very much like the sound of the AR-5......If I were asked to recommend a model for acoustic and vocal reproduction at low to moderate volume levels, I would not hesitate to recommend the 5."


* post 60, from Roger: ".........I bought the 5s because they matched my personality."



Still, it's been a little surprising to me that there has not been more commentary on Roger's unique cabinets. Not only have I never seen any AR speakers with an after-market application of plastic laminate, but I've also never seen AR-5's in unfinished pine (yes, it was an offered option, but it is a rare finish on a somewhat rare model). Unlike the AR-2's that often had one long surface without veneer (requiring horizontal placement, consistent with the dual tweeter dispersion), these AR-5's have one of the smaller surfaces without laminate, indicating that the original owner always used them in the vertical position. In the more distant pics (post 14), the faux walnut surprisingly looks reasonably convincing, but what struck me right away was the lack of mitered corners along the front edges. Even though my own woodworking skills are rather limited, it occurred to me that with a bit more care in creating miters at these corners, the objective of "re-creating" the more popular oiled walnut look might have been far more successful.



Really great thread.


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Dear Tom,

Thank you for your detailed reply. Steve F´s can of worms has now been re-opened.

I agree that good sound reproduction should not be subjective. Unfortunately it is impossible to hear how speakers, amplifiers or even cables do sound on their own. If we are listening music from stereo set, source, music, amplifier, cabling, stands, acoustical and electrical environment do have some effect how and what we hear. Acoustical environment and power amplifier interface is likely most important to how speakers do perform. It is also quite difficult to know how source material should sound. Acoustics of recording place, microphones, microphone amplifiers, mixers and producer will alter the original sound anyway. If we do not know how our recording should sound, comparison can not be objective.

Objective measurements can explain quite much how system or speakers do sound. You will find some measurements made to Spendor BC1 recently. http://troelsgravesen.dk/vintageBC1.htm

You may note how on axis response is within +- 1dB 200-3000 Hz and HF up to 20K without grille is +- 3dB. Cumulative spectral decay does not look bad either for 20 years old used speaker.This information is not enough for determining if speaker is good or bad. Phase response and directivity do have considerable effect to imaging capability of speaker.

I can agree that there is not good or bad coloration. But... if you look at Harwoods 1977/3 BBC RD Report http://downloads.bbc.co.uk/rd/pubs/reports/1977-03.pdf , you will note that ear is more sensitive to mid range coloration. Something like -20 dB is enough at 200Hz but -30dB cabinet coloration figure is needed at 5KHz. My comment about lack of articulation was inaccurate, but I hope that you will understand what I did mean.

Sloping spectral balance of concert hall has been used on many speakers. If we try to archive correct balance in living room, this means that recordings must be equalized to take this sloping balance in account. If recordings are made this way, truly flat speakers are not flat anymore. How we do listen to the music will influence quite much to desired dispersion characteristics of speaker. If we like to read newspapers while listening music wide dispersion would be desirable. If we like to listen more intensively and wish to concentrate to soundstage, narrower or closer listening window might be more desirable as this will lessen ill effects of room acoustics.

50 000 000 fans can not be wrong. Smaller size and stereo were certainly not only reason for 32% market share of AR. As I said, good engineering and mass production provided good and accurate speakers to peoples on both sides of Atlantic. Comparison to BC1 is a bit unfair, even BC1 was introduced few years before latest incarnation of AR3. Maybe it is more accurate to say that AR3aImproved was last European face lift to 3a, not entirely new model.

As I do not understand too much about speaker design, it is nice to have this opportunity to discus about AR design. I appreciate very much vintage designs. Old designs were seldom replaced next year with new improved (cheaper to make) models. If something is good for 5-20 years continuous production run, original design must be good.

As I am younger than experts on this site, I do not understand completely how things were in 50`s er even in 70´s. But, I like to learn how and why things were made in these days... and how AR3a compares to AR5 and Ar2ax.

It is nice to note that this site is open to discussion....

Best Regards

Kimmo

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Dear Kimmo,

>"I agree that good sound reproduction should not be subjective. Unfortunately it is impossible to hear how speakers, amplifiers or even cables do sound on their own. If we are listening music from stereo set, source, music, amplifier, cabling, stands, acoustical and electrical environment do have some effect how and what we hear. Acoustical environment and power amplifier interface is likely most important to how speakers do perform. It is also quite difficult to know how source material should sound. Acoustics of recording place, microphones, microphone amplifiers, mixers and producer will alter the original sound anyway. If we do not know how our recording should sound, comparison can not be objective."

The point I was trying to make is that—within the realm of high-fidelity sound reproduction and as the name implies—speakers, amplifiers and cables should not introduce any personality of their own, at least not intentionally. The object of high-fidelity equipment is to be a neutral as possible without interjecting sounds of its own; i.e. the accurate recreation of the reproduced sound. This is one reason that AR speakers were so popular through the years: natural sound reproduction without the introduction of too many sounds of their own. Naturally, many things will affect this reproduction, such as room acoustics and the original recording hall and so forth, but the reproduction chain should treat the input signal in a neutral fashion without introducing new sounds of its own. These new sounds—not a part of the original recording—would then be considered "coloration." Another way to put it is that the reproducing equipment should not "add to" or "subtract from" the original program material.

>"Objective measurements can explain quite much how system or speakers do sound. You will find some measurements made to Spendor BC1 recently. http://troelsgravese.../vintageBC1.htm

You may note how on axis response is within +- 1dB 200-3000 Hz and HF up to 20K without grille is +- 3dB. Cumulative spectral decay does not look bad either for 20 years old used speaker.This information is not enough for determining if speaker is good or bad. Phase response and directivity do have considerable effect to imaging capability of speaker. I can agree that there is not good or bad coloration. But... if you look at Harwoods 1977/3 BBC RD Report http://downloads.bbc...rts/1977-03.pdf , you will note that ear is more sensitive to mid range coloration. Something like -20 dB is enough at 200Hz but -30dB cabinet coloration figure is needed at 5KHz. My comment about lack of articulation was inaccurate, but I hope that you will understand what I did mean."

The problem with many measurements made today is that they only tell part of the story. For example, a 1-meter, on-axis, frequency-response measurement of a loudspeaker is a very popular (and important) means of testing, yet while it is very important to speaker designers for checking consistency and for detecting issues or problems with designs, it does not give an adequate picture of how a speaker will sound in a room. Some designers will tell you that they can detect the spectral balance and in-room sound—even the acoustic-power response—of a speaker by simply taking this measurement, and perhaps some astute engineers can do this. But it is easy to demonstrate the fallacy of the simple full-spectrum, sine-wave frequency-response measurement (gaited or anechoic) by simply moving the microphone from one position to another, higher or lower, changing the distance to the speaker, and taking the same measurement again. The results will be different every time, even with modern gaited measurement equipment or the even more definitive anechoic-chamber measurements. Peaks and dips move up and down the frequency domain. So what then is correct? The goal, of course, is to have a speaker with excellent measure frequency response that also demonstrates excellent acoustic-power response well back in the listening environment, not always an easy goal. Some of the newer constant-directivity horns approach this goal.

>"Sloping spectral balance of concert hall has been used on many speakers. If we try to archive correct balance in living room, this means that recordings must be equalized to take this sloping balance in account. If recordings are made this way, truly flat speakers are not flat anymore. How we do listen to the music will influence quite much to desired dispersion characteristics of speaker. If we like to read newspapers while listening music wide dispersion would be desirable. If we like to listen more intensively and wish to concentrate to soundstage, narrower or closer listening window might be more desirable as this will lessen ill effects of room acoustics."

If you go to a concert hall, or a jazz session, or even a rock concert, the music you hear is usually a highly mixed combination of direct and reflected sound. Arguments flow back and forth about this, but tests over the years—especially by esteemed acoustics experts such as Leo Beranek—have shown clearly that once you are back some distance from the performers, you are predominantly in the field of reflected energy. This is especially true of non-sound-reinforced performances such as classical-music concerts and even jazz productions in large venues without the benefit of banks of loudspeakers reinforcing the sound. So, if you go to a concert and sit anywhere other than on the first row, you are likely to get mostly reflected sound with at least enough direct, first-arrival energy to be able to tell the direction of the source of the music. This is the way it should also sound in your listening room, and it takes speakers with wide dispersion to be able to recreate the ambience of a concert hall if you listen back in the room. Speaker with very directional midrange and tweeter drivers often will appear more "focused" or "realistic" or whatever, when listened to in close proximity. They will have what seems to be a less diffuse sound, and they will "image" better than speakers with very wide dispersion. The downside of these speakers (and I have owned quite a few with these characteristics) is that once you get well back into the reverberant field in your listening room, these speakers become less three-dimensional, and they can actually sometimes even sound dull because the sound is not dispersed adequately to project back into the reverberant field. So, you have to pick your poison: do you want that "imaging" characteristic or do you want the spaciousness of the more diffuse sound. It's not easy to have both, but a few speakers—notable the all-conquering Acoustic Research AR9—have managed to accomplish both pretty well.

So... back to the question of how well the AR-5 compares with the AR-3a. This was a good discussion started by Steve F, and he answered it pretty well I think. The AR-3a's deep bass does tend to call attention to itself more than the less-potent AR-5 bass, and perhaps this is part of it. A generally heavier bass output is apparent with the 12-inch woofer, and it is more apparent than the bass output of the AR-5 or AR-2ax, but there are no issues with regard to transient response, flatness of response or anything else regarding either system.

I have attached another anechoic-chamber test measurement on the AR-3a midrange driver showing its extremely flat on-axis response through much of its operating band. There is very little deviation from flat.

—Tom Tyson

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So... back to the question of how well the AR-5 compares with the AR-3a. This was a good discussion started by Steve F, and he answered it pretty well I think. The AR-3a's deep bass does tend to call attention to itself more than the less-potent AR-5 bass, and perhaps this is part of it. A generally heavier bass output is apparent with the 12-inch woofer, and it is more apparent than the bass output of the AR-5 or AR-2ax, but there are no issues with regard to transient response, flatness of response or anything else regarding either system.

I have attached another anechoic-chamber test measurement on the AR-3a midrange driver showing its extremely flat on-axis response through much of its operating band. There is very little deviation from flat.

—Tom Tyson

Tom,

There is a difference in the character of the lower mid response between the 5 and the 3a. I don't think it has anything to do with the quality of the AR-3a and AR-5 midrange drivers. I'm sure it has more to do with the mid/woofer interaction in the crossover region, and how the woofers deal with the mid frequencies.

Roy

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Tom,

There is a difference in the character of the lower mid response between the 5 and the 3a. I don't think it has anything to do with the quality of the AR-3a and AR-5 midrange drivers. I'm sure it has more to do with the mid/woofer interaction in the crossover region, and how the woofers deal with the mid frequencies.

Roy

Roy et al,

This forum is fabulous, and Roy I so much enjoy your succinct responses here and in other forums! It speaks to your knowledge and passion for these wonderful vintage specimens. The fact that you are willing to share your experience in such an unselfish way speaks to the person, and I am very happy to have "met" you in these forums.

Geoff

p.s. ra.ra I have clarified my post in the other thread about Estate sale AR-3s

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Tom,

There is a difference in the character of the lower mid response between the 5 and the 3a. I don't think it has anything to do with the quality of the AR-3a and AR-5 midrange drivers. I'm sure it has more to do with the mid/woofer interaction in the crossover region, and how the woofers deal with the mid frequencies.

Roy

Hmmmm...in order for this to be a factual matter of 'mid/woofer interaction in the crossover region and how the woofers deal with the mid frequencies,' there would probably be some actual, tangible measurement artifact that we could all see and point to. An "Aha!" artifact.

But I'm not aware of one. Is the FR of the 5 and 3a measurably and visibly different from each other in the 500-700 Hz (the crossover) region? Not in any test I've ever seen or review I've ever read.

Neither woofer is anywhere near its directional region either: Taking 13560 and dividing by the effective pistion diameter of the driver (say 9" for the 5, and 10" for the 3a's "small" 12" woofer), neither will become directional until at least 1300-1500 Hz. They cross over a full octave below that, so that's not the issue.

Is the 3a's heavier, larger woofer "slower" than the 5's? Does it have poorer transient response, causing it to sound "thick" in comparison to the 5?

Nope. The 3a's woofer has never been measured or shown in any objective test to be sub-par in these aspects of performance.

I'll stick by my original resoning: the 3a's deeper bass than the 5 results in a different spectral balance than the 5, exascerbated by the Classic AR's already reticent high end.

The proof to my ears is this: When playing a 3a, advance the treble control to about 2:00 (perhaps 4 dB or so), and voila! The 3a sounds about perfect! No thickness, no heaviness, no "slowness." More "proof" to my ears: Later AR 12" 3-ways that used the same or very close to same 1 1/2" dome mid (the 11, 91, 58s) all sounded great. No thickness or slowness in the mid region. Reason? The highs were stronger in those FF-cooled models compared to the 3a. It's a spectral balance issue, not a woofer-midrange crossover region response or interaction issue.

The 3a's and 5's FR through the midrange is fine. The x-o region is fine. The 10" and 12" woofers both have excellent transient response and neither is anywhere near directional--not even close--by their 525/575 or 550/650 x-o points.

Again--just boost the treble about 4 dB when playing a 3a and all its problems magically disappear. Like waving a wand--the "thickness" is gone.

That's my take. As Kent so accurately says, YMMV.

Steve F.

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In the 1960s time after time AR3 and AR2ax sounded muffled, muted, lacking in treble, bland, call it what you like. Some generous people called it "polite." Phooey on politeness. My reference was and remains live unamplified performances of acoustic instruments. With musicians in my house and owning 3 pianos and assorted violins and violas, having attended countless live concerts I have the sound of live acoustic instruments well drummed into my head. One time I had a chance to directly compare the sound of AR3 with KLH model 17 for an extended period. AR3's bass was clearly far superior but from there on up there was no contest. KLH model 17 won hands down. Therefore I was surprised at what was until recently an unexplainable strong similarity between live music and recordings played through AR3 at the two demos I heard IHF trade shows in NYC in the 1960s. In the first one played against a guitar I was directly on axis and the AR3 was imperceptibly brighter than the guitar. In the second, Tom's statements to the contrary notwithstanding, The AR3s were on or near the floor while the nickelodeon was high on a table. The AR3 speakers flanked the table and AR4xs flanked the AR3s. The tonal similarity however was remarkable with full treble. In addition to most people operating these speakers with their controls in the "dot" position which is not their flattest response, as I now understand it Roy Allison who conducted the demos boosted the treble control on his Dynaco PAS3X preamplifier. This flattened the FR considerably. It was typical for audiophiles to always operate their preamps in the flat position and the obsession was so great, equipment manufacturers of better preamplifiers put a tone control bypass button on their equipment and then eliminated tone controls altogether. The last thing in the world an audiophile would consider is a graphic equalizer. That may be for the better since most in my experience don't know how to make the best use of them, expect instant results, and invariably fail. Nor are automatic equalizers called "room correction" particularly effective in correcting FR errors to the satisfaction of my ears. Having restored a pair of AR2axs when first turned on and played flat they had the same defective sound I'd remembered from the 1960s. However, with judicious adjustment of the level controls, tweeter full up, midrange slightly below the dot setting and appropriate equalization to boost the bass and treble and cut a small peak in the midrange AR2ax proved itself to be an outstanding performer with very high accuracy and not requiring outboard supplemental tweeters as all other speakers including AR9s do IMO. Placed diagonally in room corner AR2ax has the same treble sound everywhere in the room. In fact AR2ax's 3/4" tweeter has far better dispersion than AR9's recessed tweeter. Additionally AR2a and AR2ax (I have both now) demonstrated astonishingly clear and powerful bass. As of now with proper equalization I'd say AR2ax is clearly superior in every way to KLH model 6. I also have two pairs of those. However, it should also be noted that while AR2ax has outstanding bass it is not in the same league with AR9. You'd have to go some to equal that even today.

The argument about HF rolloff of sound heard in concert halls to rationalize classic AR speaker performance by Villchur in the 1960s and the same argument used to design speakers for BBC in the 1980s is a flawed argument. These measurements were based on steady state response to what is clearly a transient phenomenon. The first arriving sound at the listener is the same you'd hear close up or out of doors with the strongest high frequency components that give sound their clarity and characteristic timbre. As the reflections die out the high frequency overtones die out faster than the middle and low frequencies. This can be seen in any text on concert hall acoustics in a graph of RT versus Frequency. By 8 kHz RT is usually about 50% of what it is at 1 KHz. Therefore unless you recreate the acoustics of a live venue you cannot accurately recreate the tone of instruments heard there. Most speaker designers today opt for brighter sounding speakers even though they are also wrong for recreating concert hall and opera house tonalities. At the current state of the art of home hi fi, the industry has not recognized this fact let alone addressed it. People seem happy enough with the current flaws in their equipment...for at least a week or two after they buy them when they start shopping for their replacements.

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In the library on this site there is a page which compares the FR of AR3a, AR5, and AR2ax. It is in the AR3a series frequency response and specifications. For some reason I can't cut and paste a link to it. These curves tell the story of what I hear. You can see right off the bat the low on axis output of the tweeter compared to the midranges and woofers. Despite the woofer having low sensitivity, AR3a tweeter pays the penalty of low on axis output for much better dispersion at the highest frequencies than contemporary tweeters that beam their high frequencies often making them shrill and piercing on axis. Look very carefully at the difference in the FR of the high end of the woofer for AR3a and AR5. There is more output from AR5 where it crosses over to the midrange dome, that is the dip where they have the same output is less for AR5 than for AR3a. AR2ax shows the crossover design defect where a 2 to 3 db peak at the woofer midrange crossover is to be expected from the graphs. And it is audible. The superiority of the AR3a woofer driver at the lowest frequencies over the AR2ax/AR5 driver is also obvious with AR 5's and 2ax's rolloff starting at a higher frequency and never making it to the left side of the graph which is 10 hz. It is also steeper than AR3a's. This points out a fact AR grappled with as well as all other speaker designers. A loudspeaker driver is a resonant device having a useful bandwidth of about 2 1/2 to 3 octaves. To cover 10 audible octaves with 3 drivers something always has to give and always did. AR9 killed the problem off with a fourth driver making it easy to cover the entire audible range. The added benefit of the super woofer design just added frosting to the cake. This low end capability results in a strange phenomenon unique in my experience to AR9, it can "take over" a room if you let it. It is unfortunate IMO that AR9 did not incorporate the tweeter section of LST using the same wide dispersion tweeters in multiples. I think if Roy Allison had a hand in it, it would have. To correct this I had to add 11 additional outboard tweeters per channel. They fire indirectly to create substantial high frequency reflections coming from above and to the front and sides of the listener the way AR LST does. With judicious equalization and use of the level controls AR9 is an excellent speaker by any standards. It's one flaw IMO is that it is not a direct reflecting speaker in my case between 200 hz and 6 kHz. To eliminate this flaw I'd have to design a speaker from the ground up. Altering AR9 to achieve these results with 4 additional LMRs and UMRs per channel would be an even more daunting task for me. OTOH, one day I might just try it.

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Soundminded - how were you able to decide upon a firing pattern for your additional AR-9 tweeters?

Does your set-up replicate the LST's pattern?

How about the tweeters that fire upward, and to the sides - how are they arranged?

Is their individual or group output adjustable in any way? Would you be able to take a photo of the set-up?

We've tried back-to-back AR-9's (with one woofer pair disconnected per channel), and have also observed an "opening up" of the overall sound, with the rear-most speaker pulled out at least 3' from the wall.

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The tweeters are each 3/8" mylars. Unfortunately they are not adjustable, not in this configuration. Back in 1987 I went to a consumer audio show for the first time in a very long time. I liked the clarity of many speakers I heard and noticed that many high end speakers had a rear firing tweeter. I'd played with a 10 band graphic equalizer with my AR9s for years with no success. No matter how I adjusted it, it just never sounded right. I decided to take a chance. I went to Radio Shack and bought a pair of 3/8" 8 ohm mylar tweeters and placed them on top of the AR9s pointing straight up. I keep the AR9s against the wall behind them exactly as recommended by AR. I liked with I heard. Then I added another pair and another pair. Adjusting the program controls to LMR-3, UMR-6 and TW to -6 and using 10 band graphic equalizer (took 2 years) I got much better results. That's how it stayed until about 2008 when I acquired 175 4 ohm Sanyo 3/8" mylar tweeters at 28 cents apiece from Parts express. These were meant as snap ons for 6 X 9 car speakers. I arranged them to hang from each other vertically 4 per side firing sideways. I wired them in a 2 series strings which were wired in parallel combinations to keep the overall impedance a reasonable 8 ohms. (remember this is in parallel with three other 8 ohm outboard tweeters and the AR tweeter. I have never damaged or shut down an amplifier this way.) With 3.3 mfd caps for the whole bunch, the same used for each of the RS tweeters something was very peculiar. I'd created a duplicate of the strange sound I'd heard and remembered from the Snell Type AII and AIIIi. It was clear what was happening, a too strong lateral reflection at probably around 6 kHz or so created this coloration. This is done acoustically by the single Snell tweeter by gluing a piece of polyurethane to the center of the tweeter dome compromising its on axis output. I listened to it for a few hours, lost interest in it and never cared to hear it or Snell type A again. Eventually I settled on 2.2 mfd raising the crossover frequency of these 8 tweeters and the peculiar sound disappeared. Re-equalization has remained the same for the last 6 years with no plans to ever change it. With Bose 901 the opposite happened. That system is bi-amplified. At about the same time I added two of these tweeters per channel in series and placed them on top of the speaker aimed at the ceiling. This in addition to the four I'd also added horizontally 3 rear and one firing forward but the forward one having a resistor bridge network that cuts its output 75% compared to each of the rear firing tweeters. It is amazing how little sound these tweeters put out but what a powerful difference they make. I've concluded that while the human ear is not nearly as sensitive to these high frequencies as it is to midrange sounds, it makes great use of what it gets. Small differences in FR, loudness, and angle of arrival of these sounds mean a lot to what I perceive. Adjusting them for the room and matching the rest of the speaker system requires a lot of patience and perseverance. In the case of Bose 901 that took 4 years.

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Tom,

There is a difference in the character of the lower mid response between the 5 and the 3a. I don't think it has anything to do with the quality of the AR-3a and AR-5 midrange drivers. I'm sure it has more to do with the mid/woofer interaction in the crossover region, and how the woofers deal with the mid frequencies.

Roy

Hmmmm...in order for this to be a factual matter of 'mid/woofer interaction in the crossover region and how the woofers deal with the mid frequencies,' there would probably be some actual, tangible measurement artifact that we could all see and point to. An "Aha!" artifact.

But I'm not aware of one. Is the FR of the 5 and 3a measurably and visibly different from each other in the 500-700 Hz (the crossover) region? Not in any test I've ever seen or review I've ever read.

Neither woofer is anywhere near its directional region either: Taking 13560 and dividing by the effective pistion diameter of the driver (say 9" for the 5, and 10" for the 3a's "small" 12" woofer), neither will become directional until at least 1300-1500 Hz. They cross over a full octave below that, so that's not the issue.

Is the 3a's heavier, larger woofer "slower" than the 5's? Does it have poorer transient response, causing it to sound "thick" in comparison to the 5?

Nope. The 3a's woofer has never been measured or shown in any objective test to be sub-par in these aspects of performance.

I'll stick by my original resoning: the 3a's deeper bass than the 5 results in a different spectral balance than the 5, exascerbated by the Classic AR's already reticent high end.

The proof to my ears is this: When playing a 3a, advance the treble control to about 2:00 (perhaps 4 dB or so), and voila! The 3a sounds about perfect! No thickness, no heaviness, no "slowness." More "proof" to my ears: Later AR 12" 3-ways that used the same or very close to same 1 1/2" dome mid (the 11, 91, 58s) all sounded great. No thickness or slowness in the mid region. Reason? The highs were stronger in those FF-cooled models compared to the 3a. It's a spectral balance issue, not a woofer-midrange crossover region response or interaction issue.

The 3a's and 5's FR through the midrange is fine. The x-o region is fine. The 10" and 12" woofers both have excellent transient response and neither is anywhere near directional--not even close--by their 525/575 or 550/650 x-o points.

Again--just boost the treble about 4 dB when playing a 3a and all its problems magically disappear. Like waving a wand--the "thickness" is gone.

That's my take. As Kent so accurately says, YMMV.

Steve F.

Steve,

The difference is not dramatic, but it is real. It is a coloration difference relative to vocals, and I have no doubt this is what is being referred to in the old reviews. The crossover slopes are very gradual in these old beasts...lots of overlap. if you don't think these woofers with very high crossover points have an influence on most of the midrange, you are kidding yourself. Just try playing a pair of 3's, 3a's, 2ax's, or 5's with the woofers disconnected! Of course we could use equalizers or tone controls to change things, but that is not the point. :)

Seriously, I know what you are saying. I am just pointing out that the difference mentioned in past reviews were not imaginary, based on many comparisons I have made in recent years of a wide variety of 5's and 3a's.

If we really want to open a can of worms we can discuss whether there are some differences between the cloth surround woofer AR-2ax and 3a vs later iterations of these models, even though we know published measurements do not address this. Again, not dramatic, but they exist, imo...

Roy

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Hmmmm, very interesting..... since you guys are taking this thread all over the place :rolleyes: my AR-5s are sounding better than ever and they are not even positioned properly sitting in the middle of the room with less than optimal spacing.

I read a comment the other day that said, take an audiophile to a live performance and the first thing they say is: "Where are the highs?" I used to say, where are the musicians? but hey, that was just the backwater I was living in.

My second wife taught strings and composition at the local university and as a consequence there was never any music in the house except the sound of her students. I went for long periods with little or no music other than what I would bump into in the course of daily life. Most of the music I did listen to was by major orchestras and/or major label recording artists. Of course I was weaned on analog sound but never missed the flaws of vinyl. At one point I started buying high end reel to reel recordings.

I never had major cash flow to buy back to back AR-9s, etc., and I don't think most people do so any argument about the lack of realism in Villchur's designs goes over the head of most of us. It is not that I don't have the technical expertise to appreciate it -- it is just irrelevant to me as I'm sure it was to Eddie. He did his thing and moved on. Roy Allison moved on but never reached the audience that the classic ARs did.

The magic is still there in the classic ARs with all the flaws and I'm loving it at the moment. Any coloration caused by the crossovers and interference between the drivers at that point in the spectrum and the perceived falloff of the higher frequencies is lost on me. My hearing certainly isn't what it used to be, I doubt it was ever flat, and I'm losing the ability to locate sounds spatially, so the entire experience is a subjective one.

Once again, these speakers, the AR-5s, match my personality but I may have to track down some 3s just to stay in the discussion ;)

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Roy et al,

This forum is fabulous, and Roy I so much enjoy your succinct responses here and in other forums! It speaks to your knowledge and passion for these wonderful vintage specimens. The fact that you are willing to share your experience in such an unselfish way speaks to the person, and I am very happy to have "met" you in these forums.

Geoff

p.s. ra.ra I have clarified my post in the other thread about Estate sale AR-3s

Thanks, Geoff....This forum is a great place. It is really a team effort, with an exceptional knowledge base to draw on.

Keep us posted on your AR-5 project!

Roy

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Seriously, I know what you are saying. I am just pointing out that the difference mentioned in past reviews were not imaginary, based on many comparisons I have made in recent years of a wide variety of 5's and 3a's.

Absolutely agreed. The difference is real. It's just my opinion that the difference is mostly caused by a spectral balance difference, not a "problem" with FR in the x-o region or any big differences between the 10" and 12" woofers with respect to their midrange performance, directionality at the top end of the passband (neither is anywhere near directional at the x-o point), or woofer transient response.

I'm a scientific kind of guy. I like verifiable, repeatable explanations for differences in audible performance.

My comment about advancing the treble control when playing the 3a wasn't a flippant comment or "cheating." The 3a's "thickness" does indeed go away when the 3a is outputting a little more treble energy.

The question is, "Why?"

Advancing a treble control that increases the output above, say, 6kHz, has no effect whatsoever on the woofer's FR or its interaction with the dome mid or the system's transient response in the 300-600 Hz region or the system's directional characteristics in the 300-600 Hz region. (That's the "thickness" or "slowness" region.)

Advancing the treble control--which changes the 3a's spectral balance as perceived by the listener--eliminates the 3a's so-called thickness.

Having greater tweeter output--as available from the 11/91/58s FF-cooled tweeters--did the same thing as advancing the treble control did on the 3a: no "slowness" or "thickness."

It's spectral balance, not a woofer-mid FR or interaction issue.

IMO anyway. I've been wrong before, but like I said, I like verifiable, repeatable, tangible scientific explanations. When it's said that there's a woofer-to-mid "interaction" issue--but that "interaction" is not defined, not measured, not visible and tangible, only"suspected" or "felt"--then my suspicions are raised.

I want an explanation that's tangible, measurable, visible.

The spectral balance explanation is scientific, it's measurable, it's repeatable, and it's tangible. Give the 3a 4 dB more treble above 5kHz, and the so-called "thickness" evaporates.

But there's enough "magic" in speaker design that we still don't know that there may well be some other "interaction issues" at play that we simply aren't able to identify, quantify and measure--yet.

Love this discussion.

Steve F.

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Thanks, Geoff....This forum is a great place. It is really a team effort, with an exceptional knowledge base to draw on.

Keep us posted on your AR-5 project!

Roy

Roy, you hit the nail on the head. ARs 30% plus market share was a team effort unmatched by any other company since.

Steve F: Would love to throw out some stereophonic theory questions for speculation but maybe should start a new thread. Will muse on that for awhile since I'm on another journey today... :)

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