History of AR and the 3a for XP-15B

[Steve F]

I’d like to try to put the AR-3a into a brief, but accurate, historical perspective so that XP-15B and others might better understand the importance and significance it holds in the history of audio and also why it appeals to aficionados of vintage equipment as much as it still does, 45 years after its introduction.

I apologize in advance if you already know this or are not interested, but here goes:

In the economic boom-times of post-WWII America, “high fidelity” music systems became popular, a staple possession in the rapidly-expanding number of middle-class households. The technology of the time was such that these systems were monophonic—single-channel, one speaker—and the speaker itself was usually a very large floorstanding model.

In 1954, Edgar Villchur (aided by his protégé, Henry Kloss) finished work on Villchur’s new “acoustic suspension” loudspeaker system, a method by which deep, distortion-free bass could be reproduced by speakers less than two cubic feet in volume—a “bookshelf” speaker. His new AR-1 was literally one-quarter the size of most speaker systems of the 1950’s. Not only was the new AR-1 acoustic suspension speaker smaller, but the actual quality of its bass reproduction in terms of extension and freedom from distortion was vastly superior to other competitive speakers. A quantum leap forward.

In 1958 when 2-channel stereo was invented and consumers were now being asked to find space for two speakers in their living room, the size and performance advantage of these new ARs made them a natural. The company flourished.

1958 saw the introduction of the AR-3. It used the same 12” woofer in the same-sized cabinet as the original AR-1, but Villchur had invented the industry’s first dome radiators: a new 2”dome midrange and a 1 3/8” dome tweeter. The new drivers offered unprecedented accuracy and smoothness of response in their respective frequency ranges and the AR-3 remained at the top of AR’s line from 1958 until the AR-3a’s introduction at the end of 1967. The -3 received enormous critical acclaim, and was widely-regarded as about the “best” speaker on the market by most serious audio writers and reviewers.

The AR-3a used newly-developed midrange and tweeter drivers, smaller than the 3’s, with improved power-handling and even wider dispersion than the already-excellent AR-3. The crossover point from woofer-to-mid was dropped from the 3’s 1000 Hz to 575 in the 3a and from 7500 to 5000 Hz for the mid-to-tweeter. This was a very low woofer-to-mid crossover point for that time period. These x-o points maintained very wide, even dispersion throughout the entire operating range of the speaker. In fact, one prominent reviewer at the time described the 3a as “perhaps the most non-directional forward-facing speaker we’ve ever tested.”

The 3a also receive excellent reviews and was heralded as a top-performer, a worthy successor to the AR-3. In fact, the 3a may be the most well-known and readily-identified speaker from AR’s “Classic” period (from 1954-1974).

Its marketplace impact was unsurpassed by any other AR speaker. The mid-‘60’s to mid-‘70’s was the time period when the stereo marketplace really came of age. This was when the Baby Boomers went to college in droves, and bought mountains of stereo gear. The 3a was king of the hill during that important time period, and the 3a was the target of all the competition, like Advent, EPI, and others. The 3a was the perfect representative of all that was right with AR at that time (superb, careful engineering, classy, understated ads/marketing, a no-nonsense appeal to sophisticated, knowledgeable consumers), and just as importantly, it was the perfect example of all that was wrong with AR. It was the victim of AR’s suicidal sales/marketing practices of that time, the ill-fated strategies that led to AR’s marketplace downfall. The 3a (like all AR speakers) was the object of disparagement in non-AR retailers, as they turned down level controls and drilled holes in the cabinets to ruin the acoustic integrity in order to push more profitable brands. AR did not pay proper attention to treating its retail dealer partners well, and as a result, they suffered from widespread mistreatment at the hands of dealers whose loyalty AR never won.

As to its sound, that’s a very personal issue. Suffice to say, AR never intended the 3a to have “precise imaging,” and anyway, the entire concept of 1980’s/1990’s-styled “audiophile imaging” was non-existent in 1967. If a more “modern” tonal balance and more precise imaging characteristics are your goal, then the AR-91, -58s, -78 LS, or -50t will probably be more to your liking.

With the 3a, AR very intentionally tried to deliver wide dispersion and a smooth far-field power response. Since ferro-fluid-cooled tweeters (standard-issue today, but non-existent in the mid ‘60’s until AR invented that as well in 1975) didn’t exist, drivers with small-diameter voice coils (like the 3a’s ¾” dome) could only handle a limited amount of power. This, of course, limited their maximum output. AR willingly sacrificed the more ‘hot’-sounding tweeter that they could have gotten with a larger cone tweeter and went with a very small diameter dome, since that provided the widest dispersion. (Dispersion is primarily a function of driver diameter vs. frequency being reproduced.)

Many competing companies took a different approach, and AR suffered at retail in ‘A-B’ comparisons because of their design philosophy: the wider-dispersion nature of their non-ferrofluid-cooled tweeters meant a somewhat subdued total HF output capability in exchange for very wide dispersion, while the wide dispersion itself meant that much high frequency energy would be lost in the relatively large ‘dead’ spaces of the typical dealer speaker demonstration room. ARs fared much better in the average home listening environment. A common comment was, “Wow! They didn’t sound like that in the store!” Add to that AR’s poor dealer relations and lack of profitability, and AR faced a tough retail situation in the 60’s and 70’s.

But AR’s fans were very loyal. They loved the tight, deep, low-distortion bass. They enjoyed the un-gimmicky, unhyped sound through the midrange and treble. The look of the Classic ARs—especially the 3a with its wide ‘picture-frame’ molding—was thought to be especially nice.

AR aficionados would characterize the 3a’s sound as smooth and natural, not exaggerated, not “showy.” Yes, there was ‘something’ about the 3a’s midrange which sometimes could sound ‘thick,’ or ‘heavy.’ But on balance, the 3a holds a very unique place in audio history, it was very highly regarded in the profession, and its popularity—for acoustic/historical/emotional reasons—remains undiminished.

I hope this puts the AR-3a in a little better context for you, so you can understand why it is held in such high regard.

Steve F.

[JKent]

Great write-up Steve!

[dynaco_dan]

I’d like to try to put the AR-3a into a brief, but accurate, historical perspective so that XP-15B and others might better understand the importance and significance it holds in the history of audio and also why it appeals to aficionados of vintage equipment as much as it still does, 45 years after its introduction.

I apologize in advance if you already know this or are not interested, but here goes:

REM: No need to ever apologize Steve for telling us about our hobby.

REM: A superb write-up, Steve.

1958 saw the introduction of the AR-3. It used the same 12” woofer in the same-sized cabinet as the original AR-1, but Villchur had invented the industry’s first dome radiators: a new 2”dome midrange and a 1 3/8” dome tweeter. The new drivers offered unprecedented accuracy and smoothness of response in their respective frequency ranges and the AR-3 remained at the top of AR’s line from 1958 until the AR-3a’s introduction at the end of 1967. The -3 received enormous critical acclaim, and was widely-regarded as about the “best” speaker on the market by most serious audio writers and reviewers.

REM: My understanding is that the AR-3 was particularly talented with jazz and similar music. Very successful with with live versus recorded demonstrations as I understand it.

REM: As a side note they used Dynaco electronics for those demos.

The AR-3a used newly-developed midrange and tweeter drivers, smaller than the 3’s, with improved power-handling and even wider dispersion than the already-excellent AR-3. The crossover point from woofer-to-mid was dropped from the 3’s 1000 Hz to 575 in the 3a and from 7500 to 5000 Hz for the mid-to-tweeter. This was a very low woofer-to-mid crossover point for that time period. These x-o points maintained very wide, even dispersion throughout the entire operating range of the speaker. In fact, one prominent reviewer at the time described the 3a as “perhaps the most non-directional forward-facing speaker we’ve ever tested.”

REM: I feel that the AR-3A tweeter could be interchanged with the AR-3 without modification.

REM: After Roy Allison revealing that the AR-3 and the early AR-2AX tweeter are one of the same.

REM: It makes tweeter scarcity not an issue for the foreseeable future at least.

The 3a also receive excellent reviews and was heralded as a top-performer, a worthy successor to the AR-3. In fact, the 3a may be the most well-known and readily-identified speaker from AR’s “Classic” period (from 1954-1974).

REM: Consumer Guide reviewed the AR-3A and KLH Twelve speaker systems and commented, choose between them, as they are the very best available at that time.

REM: I was not informed as to KLH speakers here in Vancouver and was not aware that the KLH Twelve is roughly twice the size of the AR-3A, ruling out bookshelf positioning.

Its marketplace impact was unsurpassed by any other AR speaker. The mid-‘60’s to mid-‘70’s was the time period when the stereo marketplace really came of age. This was when the Baby Boomers went to college in droves, and bought mountains of stereo gear. The 3a was king of the hill during that important time period, and the 3a was the target of all the competition, like Advent, EPI, and others. The 3a was the perfect representative of all that was right with AR at that time (superb, careful engineering, classy, understated ads/marketing, a no-nonsense appeal to sophisticated, knowledgeable consumers), and just as importantly, it was the perfect example of all that was wrong with AR. It was the victim of AR’s suicidal sales/marketing practices of that time, the ill-fated strategies that led to AR’s marketplace downfall. The 3a (like all AR speakers) was the object of disparagement in non-AR retailers, as they turned down level controls and drilled holes in the cabinets to ruin the acoustic integrity in order to push more profitable brands. AR did not pay proper attention to treating its retail dealer partners well, and as a result, they suffered from widespread mistreatment at the hands of dealers whose loyalty AR never won.

REM: I still remember a large local hifi salon demonstrating AR-3A's against Double Advents and a whole host of much more expensive floor standing speakers.

REM: The tweeters were not functioning in either AR-3A but when sitting back and comparing it was not so obvious to me or my big brother. They really put on a great show, that is for sure.

REM: This took place when I was working at the local AR warantee depot.

REM: I did check the speaker level controls when the owner stepped out of the room.

As to its sound, that’s a very personal issue. Suffice to say, AR never intended the 3a to have “precise imaging,” and anyway, the entire concept of 1980’s/1990’s-styled “audiophile imaging” was non-existent in 1967. If a more “modern” tonal balance and more precise imaging characteristics are your goal, then the AR-91, -58s, -78 LS, or -50t will probably be more to your liking.

With the 3a, AR very intentionally tried to deliver wide dispersion and a smooth far-field power response. Since ferro-fluid-cooled tweeters (standard-issue today, but non-existent in the mid ‘60’s until AR invented that as well in 1975) didn’t exist, drivers with small-diameter voice coils (like the 3a’s ¾” dome) could only handle a limited amount of power. This, of course, limited their maximum output. AR willingly sacrificed the more ‘hot’-sounding tweeter that they could have gotten with a larger cone tweeter and went with a very small diameter dome, since that provided the widest dispersion. (Dispersion is primarily a function of driver diameter vs. frequency being reproduced.)

But AR’s fans were very loyal. They loved the tight, deep, low-distortion bass. They enjoyed the un-gimmicky, unhyped sound through the midrange and treble. The look of the Classic ARs—especially the 3a with its wide ‘picture-frame’ molding—was thought to be especially nice.

AR aficionados would characterize the 3a’s sound as smooth and natural, not exaggerated, not “showy.” Yes, there was ‘something’ about the 3a’s midrange which sometimes could sound ‘thick,’ or ‘heavy.’ But on balance, the 3a holds a very unique place in audio history, it was very highly regarded in the profession, and its popularity—for acoustic/historical/emotional reasons—remains undiminished.

I hope this puts the AR-3a in a little better context for you, so you can understand why it is held in such high regard.

Steve F.

[tysontom]

I’d like to try to put the AR-3a into a brief, but accurate, historical perspective so that XP-15B and others might better understand the importance and significance it holds in the history of audio and also why it appeals to aficionados of vintage equipment as much as it still does, 45 years after its introduction....

...I hope this puts the AR-3a in a little better context for you, so you can understand why it is held in such high regard.

Steve F.

Steve's brief historical sketch on AR and the AR-3a in response to "XP-15B's" initial inquiry about the AR-3a was excellent. I hope that it will clarify the overall perspective of AR speaker sound quality for "15B." I would like to address just a couple of comments made by XP-15B specifically about the AR-3a. My comments are not intended to disproved XP-15B's ideas, but simply to clarify them in relation to the AR-3a.

Here goes:

"For years I have lived with a pair of vintage, AR-3a loudspeaker… What I have loved about the AR-3a is that the overall picture is smooth, even-handed, and highly musical. They are not the perfect speaker. In fact, speakers in general, represent a series of compromises."

This was an interesting post by "XP-15B" and reminiscent of many we have heard in the past. His assessment was predictable but naïve and appears to demonstrate a lack of understanding of acoustics in home-sound reproduction. It also overlooks the varied design goals of loudspeaker designers over the years. "15B" seems conflicted about the sound of the AR-3a and can't understand why the speaker sounds the way it does. By the way -- and this is very important XP-15 -- the AR-3a does not have any "uncontrolled resonances" within its normal operating output-energy levels. If you apply 2,000 watts to it, you might get some "uncontrolled resonances," otherwise known as distortion. Otherwise, forget the "uncontrolled-resonances" theory.

"The original tweeter lacks refinement and sophistication on a number of levels. A suitable replacement is necessary.

Well, no. The original AR-3a tweeter does not lack refinement or sophistication when it comes to smoothness, lack of distortion, off-axis dispersion and smoothness of sound reproduction. The physical appearance and the use of foam suspension on a flush-mounted hard-dome tweeter may seem "unsophisticated," and the spectral balance of the AR-3a with reduced on-axis output gives the speaker a reticent, laid-back character. But as we all know, the ¾-inch hard-dome AR-3a tweeter -- in its original state -- remains pretty much unsurpassed in overall performance except for the Allison tweeter. Can anyone name a single tweeter, other than the Allison: One tweeter that is measurably smoother overall with better off-axis performance? Simply shoving in another tweeter into the AR-3a tweeter hole without crossover changes will not improve results as much as creating an imbalance in sound output. It may initially sound good, but in the long term it will probably result in listener fatigue due to improper integration with the original system. That said, it is important to remember that there are few existing AR-3a tweeters that are still in original-operating condition, meaning that the suspensions have deteriorated.

"The AR-3a does not image well. The drivers are recessed into a cavity and are not lined up straight, nor are they mirror-imaged. This issue could potentially be solved by making a new baffle for the front, mounting the mid driver in the center and making a headpiece for the tweeter. Were it not for other unsolvable issues with the speaker, I would consider doing this. For the time being, I've installed a layer of carpet felt around the drivers to minimize diffraction and to help in bringing things more into focus."

Correct. The AR-3a is not supposed to image well and wasn't designed to "image," to use that nebulous term. If "15B" craves imaging, this is not the speaker for the task. Get a speaker with an 8-inch, highly directional midrange driver. AR speakers were designed to have flat-power response, not flat on-axis response, in the reverberant listening environment. Taken further, it is well known that each AR driver is pretty much "ruler-flat" measured individually in an anechoic chamber, but when these drivers are integrated with the system and measured within at one or two meters on axis, up-close, in a typical listening environment, there will be a lot of interference, lobing and diffraction, but these effects are not audible in the far field. This is easily demonstrated by moving a microphone around to different positions during a near-field measurement, and the peaks and dips move around to different frequencies. The result is that an AR-3a looks like a "mess" when measured this way. But when the AR-3a is measured back in the normal listening environment for which it was intended (i.e., AR-3a back against the front wall with the listener well back in the listening room in a sort of isosceles triangle arrangement), is a very smooth, effortless and pleasing sound reproducer. So why does the AR-3a sound so good, smooth, accurate, when listened in a typical listening room? How is this mystery possible? The reason is that most listeners don't listen simply to first-arrival sound, but to the reverberant sound energy that is reflected in the room. These trends have changed through the years, but when the AR-3a was king, people put the speakers back against the front wall and had listening positions well back in the room.

"The 12" bass/midrange is run up too high, resulting in chesty, whompy, colorations that bleed into the midband. This effect is especially obvious if you, for example, listen to a female vocal on a pair of Quad ESL 57 electrostatic loudspeakers and then compare with the AR-3a. You can hear, quite obviously, the woofer bleeding into the lower registers of the voice and polluting it's clarity and effortless quality."

No, again. The AR-3a is not out of control, "giving colorations that bleed into the midband." The 12-inch woofer in the 3a is actually well-behaved and easily within its clean-operating pass band. However, XP-15B is right that the crossover on the AR-3a would be ideally lower in frequency for better dispersion and integration with the midrange -- the exact thing that was done in 1978 with the all-conquering AR9. Consumer Reports noted a heaviness in the AR-3as lower midrange/upper bass when they initially evaluated the speaker some years back, but their finding was questioned, and they also found issues with both the midrange driver and the woofer, so it appeared to be more of a crossover issue.

--Tom Tyson

[kirk57]

Very interesting history, but a bit distressing reading this:

it is important to remember that there are few existing AR-3a tweeters that are still in original-operating condition, meaning that the suspensions have deteriorated.

Sorry this is a bit OT, but I have to ask:

Having searched the CSP archives, I've concluded that

1) most if not all of the original tweeters have deteriorated

2) there really is no modern equivalent replacement (quite possibly because the design goals of the originals are not the design goals of 'modern' drivers)

So my question is, given that I just got my AR-3a's, how (short of inventing a time machine) do I know how the things are really supposed to sound? The only options seem to be new tweeters that change the basic sound signature of the speaker (even with crossover mods), or using likely deteriorated/out of spec original tweeters.

[tysontom]

Very interesting history, but a bit distressing reading this:

Sorry this is a bit OT, but I have to ask:

Having searched the CSP archives, I've concluded that

1) most if not all of the original tweeters have deteriorated

2) there really is no modern equivalent replacement (quite possibly because the design goals of the originals are not the design goals of 'modern' drivers)

So my question is, given that I just got my AR-3a's, how (short of inventing a time machine) do I know how the things really supposed to sound? The only options seem to be new tweeters that change the basic sound signature of the speaker (even with crossover mods), or using likely deteriorated/out of spec original tweeters.

Kirk57,

It is not known exactly what the attrition is for the AR-3a tweeter. The foam under the dome nearly always deteriorates, but the foam suspension may remain effective on some tweeters. The AR-3 tweeter uses a slightly different formulation, and it might not be as adversely affected.

There are indeed several good replacement tweeters. Several members on this site have successfully replaced the tweeters with newer units with slight changes to the crossover, and they get good results. No replacement is exactly equal to the old one in dispersion, but nearly all of the new ones have increased on-axis energy, which "brightens" up the sound of the speaker somewhat. These are very worthwhile replacements.

Also, the basic spectral balance of the speaker will not be grossly changed if the replacement tweeters are small-diameter domes with the added crossover changes. Therefore, the AR-3a will still sound close to the original if this is done properly. The point we have been trying to make, however, is that you should not just stick in any tweeter and think it will work properly. Take the advice of the people on this site, and open the document "Restoring the AR-3a" on this site as well for further insight.

--Tom Tyson

[dynaco_dan]

Steve's brief historical sketch on AR and the AR-3a in response to "XP-15B's" initial inquiry about the AR-3a was excellent. I hope that it will clarify the overall perspective of AR speaker sound quality for "15B." I would like to address just a couple of comments made by XP-15B specifically about the AR-3a. My comments are not intended to disproved XP-15B's ideas, but simply to clarify them in relation to the AR-3a.

Here goes:

--Tom Tyson

Hi Tom

Great writing and clarification as always.

[kirk57]

Kirk57,

It is not known exactly what the attrition is for the AR-3a tweeter. The foam under the dome nearly always deteriorates, but the foam suspension may remain effective on some tweeters. The AR-3 tweeter uses a slightly different formulation, and it might not be as adversely affected.

There are indeed several good replacement tweeters. Several members on this site have successfully replaced the tweeters with newer units with slight changes to the crossover, and they get good results. No replacement is exactly equal to the old one in dispersion, but nearly all of the new ones have increased on-axis energy, which "brightens" up the sound of the speaker somewhat. These are very worthwhile replacements.

Also, the basic spectral balance of the speaker will not be grossly changed if the replacement tweeters are small-diameter domes with the added crossover changes. Therefore, the AR-3a will still sound close to the original if this is done properly. The point we have been trying to make, however, is that you should not just stick in any tweeter and think it will work properly. Take the advice of the people on this site, and open the document "Restoring the AR-3a" on this site as well for further insight.

--Tom Tyson

Tom-

I appreciate the response.

I've read the "Restoring the AR-3a" doc over many times, and would certainly follow the recommendations there if I need to replace the tweeters. Until then, I'll just hope that my originals ones are still fairly close to being in proper working order....

[tysontom]

Hi Tom

Great writing and clarification as always.

Hi Vern!

Thanks for your comments!

--Tom

[tysontom]

Tom-

I appreciate the response.

I've read the "Restoring the AR-3a" doc over many times, and would certainly follow the recommendations there if I need to replace the tweeters. Until then, I'll just hope that my originals ones are still fairly close to being in proper working order....

Kirk57,

You bet. When it comes to the 3a tweeter, if it appears to be working okay and sounds fine, don't worry about it. I think that what we're trying to say is that these 40-year-old AR-3as will probably not meet original specs, but they still sound fine in most cases. I have several sets of AR-3as (some on loan to relatives), and all of them (and a pair of AR-LSTs) have good-working tweeters. I'm sure that they would not meet original specs, but they don't have problems or audible distortion, so I am staying the course.

Besides, just positioning the speakers properly in your listening room will probably have more effect on the sound you hear than an out-of-spec tweeter.

[RoyC]

Kirk57,

You bet. When it comes to the 3a tweeter, if it appears to be working okay and sounds fine, don't worry about it. I think that what we're trying to say is that these 40-year-old AR-3as will probably not meet original specs, but they still sound fine in most cases. I have several sets of AR-3as (some on loan to relatives), and all of them (and a pair of AR-LSTs) have good-working tweeters. I'm sure that they would not meet original specs, but they don't have problems or audible distortion, so I am staying the course.

Besides, just positioning the speakers properly in your listening room will probably have more effect on the sound you hear than an out-of-spec tweeter.

As always, great perspective from Tom and Steve.

I agree with Tom regarding the tweeters. Having spent a number of years working on the replacement tweeter issue, I would like to add some other comments.

As soon as XP-15B installed the Seas tweeter without any crossover modifications his speakers ceased being AR-3a's. I'll defer to Tom's post above regarding that, and try to clarify below.

There are three primary issues when looking for the ideal replacement tweeter:

-The first is the unusually big cabinet hole for those who are looking for an easy "drop-in" replacement.

-The second is that every viable modern replacement tweeter (without exception) has a frequency response that extends much further into the midrange than the unique original AR tweeter. This requires modification to the original crossover to bring the tweeter (regardless of how "good" or expensive it is) even close to the original tweeter's response. The original tweeter would be defined as a "super tweeter" today as its primary contribution is at very high frequencies. It mechanically rolls off very quickly using a very simple series capacitor crossover.

-The third is capturing the elusive dispersion characteristics of the original tweeter.

The HiVi Q1R tweeter, which I first mentioned as a possible alternative (with a slight crossover modification) to the original, is only recommended as a replacement when original tweeters are not available. It is NOT intended to be a modification to improve the 3a or any of its siblings. It is simply a way to approach the tonal balance of the original design, and hopefully allow the speakers to continue to be useful in a satisfying way.

Recent experimentation with several modern dome tweeters, including the HiVi tweeter and XP-15B's Seas tweeter, suggests that none of them act the same as the original tweeter at the very highest frequencies (over 5000hz). Further, a 30% to 50% reduction in the tweeter crossover capacitor value may also be necessary (along with the previously recommended .05mh parallel inductor) to prevent the new tweeter from producing an imbalance in the upper midrange. This imbalance overemphasizes the upper midrange, and exacerbates what XP-15B is describing in the lower midrange. It is most noticeable at higher volume levels.

For the time being it is best to stick with the original tweeters unless there is an obvious problem or they are missing. Many folks restoring these older AR models believe there is a problem when they cannot seem to clearly hear what is coming out of the tweeters. That is the way the system was designed! Add to that the fact that many restorers of these old beasts have "older" ears, which complicates matters even more.

Roy

[soundminded]

There's an endlessly repeated mantra that such and such a speaker is not a perfect speaker, that the perfect speaker hasn't been invented yet, that a pulsating sphere or some other such thing would create a perfect speaker. I think this notion lacks insight into the basic nature of the problem of a recording/reproducing high fidelity sound system which incorporates many elements from the selection and placement of microphones, the recording venue, the arrangement of musicians all the way through to the sound arriving at the listener's ears. The loudspeaker is only one element in that chain, there being many others each with its own variables that affects the final outcome.

The first problem is is to define what a high fidelity sound system is supposed to achieve. If it is what has been called "accurate reproduction" the next question is what does that mean? The question has more than one correct answer. The sound of acoustic instruments heard at a live venue? The sound as they would be heard in your room? I make a distinction between two different kinds of recordings although it isn't necessarily a sharp one. One kind is what I think of as documented sound. This even where the signal is manipulated is intended to create an end sensation as closely as possible to hearing a live musical performance. The other is what I call manufactured sound, an effort to create a pleasing result that doesn't necessarily reflect any possible live performance. Both have the goals of being commercially successful but they cater to different markets. Many of us are consumers in both markets. For this second market, the term accuracy therefore has no meaning. Accuracy and any other subjective evaluation can only be determined by the listener based on memory. This is true even for rapid fire A/B comparisons and live versus recorded comparisons.This is because sound is an event experienced in time and you can't experience two of them simultaneously and make any sense of it.

Taken in that context, there are no perfect sound systems commercially available today. AR3 demonstrated to me on two occasions that under highly contrived circumstances and in a very specific context, it could come very close to achieving the goal of second definition of accuracy I gave above. But not without other elements used to achieve that goal, namely not merely the way the recording was made but electrical manipulation of the signal, namely a treble boost on the playback preamplifier. There is nothing wrong with this, it's part of a system. The availability of low cost multiband graphic equalizers can to a great degree reduce the differences between loudspeaker systems and remove otherwise objectionable resonances that are created somewhere in the system. But there's much more to solving the problem than that and they can't all be solved by trying to create the perfect loudspeaker. AR3 and AR3a proved benchmark products that were capable of achieving excellent results at modest cost reliably in a wide variety of circumstances if you knew how to use them to their best advantage. Most of us didn't. The obsession of keeping tone controls flat is just one of the ways users of these products compromised what they had to offer. More later.

[XP-15B]

I love Acoustic Research. The company's products have brought me much, much enjoyment.

[dynaco_dan]

I love Acoustic Research. The company's products have brought me much, much enjoyment.

Hi there

Amen to that statement.

[Aadams]

The availability of low cost multiband graphic equalizers can to a great degree reduce the differences between loudspeaker systems and remove otherwise objectionable resonances that are created somewhere in the system. But there's much more to solving the problem than that and they can't all be solved by trying to create the perfect loudspeaker. AR3 and AR3a proved benchmark products that were capable of achieving excellent results at modest cost reliably in a wide variety of circumstances if you knew how to use them to their best advantage. Most of us didn't. The obsession of keeping tone controls flat is just one of the ways users of these products compromised what they had to offer. More later.

Soundminded has pointed out something that I have noticed. Once I got my AR3a pair sounding "right" I was able to use a graphic equalizer to make a pair of DCM Timewindows (with a subwoofer) sound remarkably similar to the ARs. (Timewindows have a tweeter arrangement like an Allison 1). I can't believe all the years of frustration that could have been avoided if I had not been so adamant about not using tone controls or outboard processors.

JMTC after months of lurking. This a great board.

Thanks

Abigail