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Loudspeaker directivity by Roy Allison


Howard Ferstler

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Berkovitz study (and consequently, early AR design) was flawed.

The paper itself demonstrates that to be the case, as I have repeatedly disclosed and discussed here in The Kitchen.

"Total power" has long since been repudiated, both as a design and listener preference metric, and the last I saw about it, CU has abandoned loudspeaker evaluation entirely.

I always refer back to the original Floyd Toole article where 16 or 20 speakers were listened to in controlled blind tests and rank ordered by listener preference, then measured in a variety of ways. When you see the power response curves of the systems ordered from best to worst you can easily see that there is no correlation between power response and ranking. Most of the most prefered systems have random holes in power response and all have a downward trend to power spectrum. Conversely, near the bottom of the rankings are a couple of systems with much smoother and flatter power response (but poor axial response).

Obviously not not an essential criterion.

Of course you can proclaim:

Toole was biased against wide dispersion speakers.

Toole's listening panel were equally biased (in a blind test).

Tooles listening rooms were atypical. (Curtains on the wall would prevent a good loudspeaker from sounding good?)

Nobody appreciates good music. Pop music doesn't warrant accurate reproduction. People prefer unnatural imaging precision to spaciousness (not something that Toole is a proponent of, actually). etc. etc.

Old beliefs die hard.

David

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Obviously not not an essential criterion.

So what does turn out to be essential measurement criteria? It doesn't have much affect on any decisions I might make about what to buy, just curious (yes, I've looked at the linked articles, but I'm not embarrassed to admit that most of their contents go way over my head).

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Since Toole et al. discovered that their ranking of speaker preferences was heavily weighted towards those with excellent on-axis FR, does that mean that speakers with nicely-controlled on-axis FR AND good far-field response might sound good, by their criteria?

I don't think Toole is saying that smooth far-field power leads to a bad sounding speaker; it's just that that alone does not make a good-sounding one. This may be the point of contention about early AR/Allison design theory and later-day (Toole etc.) on-axis proponents: that Allison felt far field predominates the perceived sound, whereas Toole feels on-axis is the prime determinate, but good far-field doesn't detract.

What people seem to overlook in this discussion is that AR presented the major benefit of their wide-dispersion domes as delivering greater placement flexibility of both the speaker and listener. Their 1970-71 lit--right smack dab in the middle of the 1967-1975 3a-5-2ax time period says it explicitly: ".....even sound coverage at all audible frequencies in all directions, not only side-to-side, but vertically as well.....whether heard directly in front or at an appreciable angle off axis."

That's how AR always presented their 'wide-dispersion domes' to the public--as having the benefit of listener and placement flexibility.

The so-called "general buying public" wasn't told about such things like AES papers and the like. Even later AR lit (1975) that showed the reverberant chamber power curves (as well as the individual driver on-axis curves) said quite clearly that speakers that measured well in both cases (on axis and power) would sound good in most situations.

Please, I'm not saying that those ARs did or did not measure well on axis or were or were not "wide dispersion."

The debate about their "near field havoc" and intrusive cab molding that inhibited their "wide dispersion" is well documented and I'm not looking to re-open that can of worms now.

I'm simply pointing out that AR presented wide dispersion as being mostly a placement/flexibility benefit.

That's how their ads read, and that's how their lit read.

Steve F.

P.S.--Another question for the Forum, especially the Pros here: If far-field power is not the thing, and near-field havoc plagued all the early ARs, why do they sound so good? "Polite" spectral balance? Nope--you can turn the treble down on another speaker and it will still sound like a garden-variety speaker, just with the treble turned down.

So what is it? Why do the 4x-6-2ax-5-and 3a sound so good? Why has their popularity held steadfast for 40+ years?

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What people seem to overlook in this discussion is that AR presented the major benefit of their wide-dispersion domes as delivering greater placement flexibility of both the speaker and listener. Their 1970-71 lit--right smack dab in the middle of the 1967-1975 3a-5-2ax time period says it explicitly: ".....even sound coverage at all audible frequencies in all directions, not only side-to-side, but vertically as well.....whether heard directly in front or at an appreciable angle off axis."

In contemporary loudspeaker parlance, that's the very definition of constant directivity, no? The question is, "How wide," and we now know how to achieve that without adversely affecting imaging and/or soundstage.

As with flat power response, it may be argued that AR's NOT accomplishing the very wide dispersion they sought was to their advantage, and that Allison failed, by comparison, because he pursued these objectives to the extreme.

So what is it? Why do the 4x-6-2ax-5-and 3a sound so good? Why has their popularity held steadfast for 40+ years?

Indeed, and my primary point here is that we cannot begin to answer that one, either, so long as we continue to hold onto these outmoded design beliefs as immutable.... :)

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What people seem to overlook in this discussion is that AR presented the major benefit of their wide-dispersion domes as delivering greater placement flexibility of both the speaker and listener. Their 1970-71 lit--right smack dab in the middle of the 1967-1975 3a-5-2ax time period says it explicitly: ".....even sound coverage at all audible frequencies in all directions, not only side-to-side, but vertically as well.....whether heard directly in front or at an appreciable angle off axis."

That's how AR always presented their 'wide-dispersion domes' to the public--as having the benefit of listener and placement flexibility.

I've never overlooked it. In fact, it's one of the first things I check for when listening to new speakers. If I have to plant myself in a tiny "sweet spot" to get full benefit from a pair of speakers, they won't work for me. .

I don't think I really have any more of an idea "why" my speakers sound good to me today than I did when I bought them, and all the mutual sniping that goes on in here is certainly not helping in that area.

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I don't think I really have any more of an idea "why" my speakers sound good to me today than I did when I bought them, and all the mutual sniping that goes on in here is certainly not helping in that area.

I have suggested a major element of the "why" at least a couple of dozen times here; it's constant directivity, and we know how to do it better now....

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So what does turn out to be essential measurement criteria? It doesn't have much affect on any decisions I might make about what to buy, just curious (yes, I've looked at the linked articles, but I'm not embarrassed to admit that most of their contents go way over my head).

Thats what we talked about in the "Goals for an Ideal Loudspeaker Threads" parts I and II. My take on the subject:

http://www.classicspeakerpages.net/IP.Boar...ost&p=84172

Here is a really good article on the subjct by Sean Olive. He has done some excellent work where he has statistically found the link between different measurements and listener preference.

http://seanolive.blogspot.com/2008/12/part...oudspeaker.html

Most important parameters: Axial response smoothness, axial response flatness, power response smoothness (revealing of resonances) and bass extension.

David

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Since Toole et al. discovered that their ranking of speaker preferences was heavily weighted towards those with excellent on-axis FR, does that mean that speakers with nicely-controlled on-axis FR AND good far-field response might sound good, by their criteria?

I don't think Toole is saying that smooth far-field power leads to a bad sounding speaker; it's just that that alone does not make a good-sounding one. This may be the point of contention about early AR/Allison design theory and later-day (Toole etc.) on-axis proponents: that Allison felt far field predominates the perceived sound, whereas Toole feels on-axis is the prime determinate, but good far-field doesn't detract.

Steve F.

Nobody would claim that very smooth (but not flat) power response is going to make a loudspeaker sound bad. Achieving flat phase response won't make a speaker sound bad. Achieving extremely low distortion won't make a speaker sound bad. Yet, since all these achievements will cost money in development or bill of material cost, the question is always: will they make the speaker sound better? There is a very real danger that strivng for one will force us to diminish more important areas.

That is why I keep talking about "necessary and sufficient" criteria. In the design process what must you do to achieve a good ranking? And what would be superfluous?

In my opinion striving for a particular power response is not the real answer. I'll follow what Lipshitz and Vanderkooy found, that flat power is perceived as too bright, that holes in the power response are generally inaudible but that peaks can be audible. Although Toole doesn't state it as directly, his data shows it clearly: speakers can sound great with poor power response, they can sound poor with smooth and flat power response.

Not a necessary criterion and may preclude achieving others that are.

David

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The debate about their "near field havoc" and intrusive cab molding that inhibited their "wide dispersion" is well documented and I'm not looking to re-open that can of worms now.

I'm simply pointing out that AR presented wide dispersion as being mostly a placement/flexibility benefit.

That's how their ads read, and that's how their lit read.

Steve F.

In large part this ongoing debate is about our pulling bits from AR and Allison to "prove" our own broader beliefs. We are in danger of overstating what Vilcher and Allison believed from fairly limited evidence.

Allison and Berkowitz did talk about power response in their study of the Boston sound rooms, but if you stand back and ask "what were the priorities in the design of early AR products?" it would be something different.

  • AR was the first company to print actual (run on GenRad equipment) response curves of some aspect of their system's performance.
    That aspect was the on and off axis free field (anechoic) response of their individual drivers under ideal (no cabinet) conditions.
    It did not include real cabinet effects which would have made the curves unpublishable.
    It did not include the actual blending between the drivers which would have made the curves unpublishable.

Viewed from the evidence, the engineering objective at AR was to get very flat direct field response from each individual driver and crossover. The 0 degree curve was flattest and the off axis curves were close behind. That is what they achieved, it was ahead of what others were achieving at the time, and nobody else was printing real machine run response curves.

The concepts of "concert hall rolloff" or "only measure in the reverberent field" appear to me to be rationalizations of the engineering aspects they couldn't perfect at the time. These were aspects awaiting engineering advances from the 70's and 80's.

Why would anybody argue that engineering advances since then haven't been true progress? If Linkwitz Riley crossovers, low diffraction cabinets and and ability to design around the 2pi to 4 pi effects are now (not then) commonplace, how is that not desirable progress?

If Vilcher could have achieved a speaker with better direct field response at the time (and could have sold a very different looking grille-less system) do you really think he would have passed on it?

I don't.

So what is it? Why do the 4x-6-2ax-5-and 3a sound so good? Why has their popularity held steadfast for 40+ years?

Not going near that one.

David

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Why would anybody argue that engineering advances since then haven't been true progress? If Linkwitz Riley crossovers, low diffraction cabinets and and ability to design around the 2pi to 4 pi effects are now (not then) commonplace, how is that not desirable progress?

David

The answer is clear and painfully simple. While it is true that ALL of the electrical problems have been solved and comoditized to the point where they are cheap (in the real world, not the high end audiophile fantasy world) compared to their cost in prior eras, and that the existing paradigm of loudspeakers has been better mathematically modeled and refined, and that available materials are better than ever, the underlying problem is no closer to solution than it ever was. That problem as orginally stated was to reproduce the audible experience of hearing live music which at the time meant acoustic, not electronically amplified musical instruments. The problem has so thoroughly and completely beaten those who have attempted to solve it, and beaten them in virtually every aspect of it, that they no longer even acknowledge that the original problem is the one they are still trying to solve. Instead they have defined a different problem which is achievable because it is defined by the limits of what they can do and that is to produce products the market likes within the context of the market's experience and what is available to it. But to those who still remember the original problem and what was promised or at least hoped for one day in the dim future possibly within their lifetimes, people like Genek, Gordon Holt, and many others, the failure of an entire industry with all of its resources of money, technology, and mountains of hype, the results thus far has come as a bitter disappointment. In those terms, the current products are as much failures as those of the prior eras were no matter which you find more entertaining. For those who are still familiar with the sound of real music, the current state of the art just doesn't cut it and the gap between what is expected and what is possible remains vast. Toole is among this failure's greatest apologists and among the strongest advocates for redefining what the problem is. The fact is that progress from the most basic research to product development in light of that task is pathetically paultry since Villchur's admittedly contrived LvR demonstrations. That was the best that could be done then, and claims to the contrary, it is not clear that even that which in itself is inadequate could be as successfully repeated today.

BTW, I disagree with Allison about the ability of loudspeakers to reproduce concert hall quality bass. With careful equalizaton, AR9 and possibly a few other speakers can reproduce concert hall bass at the SPLs it would be heard live in most of the audience. That is among my experiences with it.

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Not going near that one.

Then I submit that you are missing the point of this website. But don't feel bad about it, your're not the only one.

For those who have bookmarked this forum and may not have visited the home page recently, the mission statement of CSP says, "Specializing in Acoustic Research and its New England Progeny." This is not AudioKarma, DIYAudio, or any of the other countless sites devoted to pro and con discussions of different audio theories or how to build or hotrod your own speakers. It's the equivalent of a site devoted to the care, feeding, restoration and history of Atwater Kent radios, Chevrolet Corvettes or Hummel figurines, but with management that is a lot more tolerant than those other sites'. Just try going to one of them and posting about how antique radios don't fit modern consumer tastes, how the '63 split window Vette gets worse gas mileage than and doesn't corner as well as a 2010 Nissan Altima or how Hummel hasn't kept up with the times by adding digital speech to its figures and see how fast the forum administrator there blows your account off the membership list.

While the site sees a fair amount of traffic from people who have to rationalize their preferences by deluding themselves that AR's designers were the only ones in audio history who ever "got it right," and by people who just bought classic ARs because they were so famous, are disappointed with their sound and want to know how to mod them to sound more like the Bose cubes they have in their living room, most of CSP's regulars have wandered into an audio dealer or two in the past couple of decades, have noticed that the world has passed our preferences by and are not losing any sleep over it.

The debates over speaker measurements and listener preferences in the Kitchen have been providing entertainment for a fair number of readers, though the statistics are a bit misleading because about half the views on the counter are your administrators monitoring the threads. For those who think a large number of views is a measure of interest, the most viewed AR-related thread in the Kitchen to date has been "In Praise of AR3a's," with 11,590 views. It comes nowhere near "8 Ohm Tweeter, Pots or L-pads," in the Acoustic Research forum at 25,354 views, and I promise you that half of those views are not your administrators monitoring the thread.

A discussion of what characteristics of classic New England speakers have made them them as appealing as they are to many people for many years is exactly where our more technically knowledgeable posters ought to be going. And when you're done with that, how about something in Mods and Tweaks about how to make a pair of Insignia bookshelf speakers from Best Buy mimic the sound of the AR-4x?

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painfully simple.... no closer to solution than it ever was.....has so thoroughly and completely beaten those who have attempted to solve it.... beaten them in virtually every aspect of it, that they no longer even acknowledge that the original problem is the one they are still trying to solve.... the failure of an entire industry with all of its resources of money, technology, and mountains of hype.... has come as a bitter disappointment.... are as much failures as those of the prior eras were.... just doesn't cut it and the gap between what is expected and what is possible remains vast. Toole is among this failure's greatest apologists ... the most basic research ..... is pathetically paultry.... Villchur's admittedly contrived LvR demonstrations..... it is not clear that even that which in itself is inadequate could be as successfully repeated today.

Hey Soundminded, where have you been for the last month? I was beginning to miss your usual rant!

David

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QUOTE (speaker dave @ May 28 2010, 04:17 AM) *

Not going near that one.

Aw, c’mon Dave, give it a shot.

In the meantime, I will:

I think there are several factors at play here, some technical and some emotional.

I think that in their day, the 4x-6-2ax-5-3a series of speakers was arguably at or near the top of what could be achieved at the time, in terms of frequency range, deep bass quality (flatness of bass FR, low THD, etc.), and lack of overall ‘nastiness’—ARs tended not to offend with a too-forward midrange or a shrill, edgy treble.

To replay ‘quality’ music from the, say, early 60’s to the early ‘70’s (various classical recordings, Dave Brubeck and Miles Davis, early Beatles, etc.), AR speakers sounded very nice. It was easy to understand their popularity at that time.

Why did they sound good? Perhaps we, as listeners, could hear through the near-field havoc and the diffraction, and actually get a sense, a quick aural glimpse, if you will, of the essential quality of those early drivers. Yes, put an x-o into the mix and surround them with some intrusive cabinet molding and all bets might be off, but the essential, intrinsic quality of those early domes and cones was pretty darn good. Very good individual FR, very low distortion, very wide dispersion. Maybe we heard that for the faintest of seconds, and it made an indelible impression on our auditory memories.

I suspect—very strongly— that that is part of the explanation.

There’s also the no-nonsense, engineering-heavy, intellectual approach that AR took with its products, its advertising, and its literature. This had a certain undeniable appeal to those people who liked to ‘know’ that the speakers they choose were well-designed, in accordance to what were thought to be the highest technical standards of the day. Choosing AR speakers conferred a particular ‘credibility’ on their owner.

Then there’s the ‘aural accommodation’ aspect of things. We just got used to how ARs sounded and tended to hold that sound up as a standard of comparison. Brighter? Edgier? Boomier? No good. No matter that ‘brighter’ may have, in fact, been more linear or less diffracted. It wasn’t what we were accustomed to, so it wasn’t as ‘good.’

Then, of course, there’s the emotional side of it. We want AR speakers to sound good. We like them. We associate them with pleasant things in our past, be they family memories or college days or “speaker wars” with our friends, or whatever those days were to you as an individual. Our mind’s “ear” flattens out all kinds of FR dips and peaks and we remember them sounding better than they actually did. Speaker Dave’s experience with pulling out a venerable Snell classic and comparing it to a current TOTL Snell and the classic sounding ‘broken’ is a perfect example. We’ve all been there.

This is a hobby, after all. Wanting classic ARs to sound good and defending them is fun, and it’s what makes a hobby enjoyable. Logic does not have to enter the picture at all, ever. Nothing ever needs to be “proven,” there is no “court of law” here and if we like the old speakers, no justification or further explanation is necessary.

Advent, Dynaco, EPI, JBL, and even KLH didn’t engender this kind of response in their owners. Only AR. I think these are among the reasons that they’ve remained so popular to this day.

Steve F.

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Hey Soundminded, where have you been for the last month? I was beginning to miss your usual rant!

David

I'm hardly surprised that anoyone in the business of making or selling this stuff would say that pointing out that the emperor has no clothes on is ranting. Progress in this industry is measured by the fact that you can now manufacture a pair of two way speakers each having a 5 inch woofer and a 1 inch tweeter and charge $4000 for it with a straight face like Merlin does and people will say and believe it is the greatest thing since sliced bread. Twenty years ago for a two way 8" speaker you could only charge around $1500 to $2000 and get away with it. So that's progress. Of course there's always Peter Qvortrops' high end TOTL 8" two way speaker that sells for $150,000 the last time I looked. I guess it depends on the price of silver and Russian Birch at any moment. Some would argue it is better than AR4x, others would say it's the other way around. I only heard it once and I'm still on the fence about it. I didn't have a chance to do an AB comparison but I was not impressed. I'd say high end audio equipment today is priced at about 50 to 100 times what it's actually worth. Small wonder it's a dying industry. Still at those profit margins you only have to sell a few units a year to stay in business....if you operate out of your garage like some people do. Zzzzzzz.

BTW, what's wrong with Snell AII among other things is that its off axis radiation at around 7-9 Khz is so great compared to its frontal radiation that reflections in that range are louder than the direct field in all but the deadest rooms. That gives it a very interesting and pleasing coloration. Having discovered it purely by accident through experimentation with other speakers I enjoyed listening to it for about a day and then never cared to hear it again. AIIIi does the same thing, it has to do with the polyurethane glued to the front of the tweeter.) Once I knew what it was and how it was done, I lost all interest in owning one. What's interesting about the AR tweeter is that its equivalent could easily be manufactured today simply by changing the geometry of the dome. Nobody cares to because that is not what is in vogue at the moment.

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But to those who still remember the original problem and what was promised or at least hoped for one day in the dim future possibly within their lifetimes, people like Genek, Gordon Holt, and many others, the failure of an entire industry with all of its resources of money, technology, and mountains of hype, the results thus far has come as a bitter disappointment.

Please try not to put words in other peoples' mouths. I have not experienced any "bitter disappointment" in modern speaker listening. At worst I would describe myself as "unenthused."

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Progress in this industry is measured by the fact that you can now manufacture a pair of two way speakers each having a 5 inch woofer and a 1 inch tweeter and charge $4000 for it with a straight face like Merlin does and people will say and believe it is the greatest thing since sliced bread. Twenty years ago for a two way 8" speaker you could only charge around $1500 to $2000 and get away with it. So that's progress. Of course there's always Peter Qvortrops' high end TOTL 8" two way speaker that sells for $150,000 the last time I looked. I guess it depends on the price of silver and Russian Birch at any moment. Some would argue it is better than AR4x, others would say it's the other way around. I only heard it once and I'm still on the fence about it. I didn't have a chance to do an AB comparison but I was not impressed. I'd say high end audio equipment today is priced at about 50 to 100 times what it's actually worth. Small wonder it's a dying industry. Still at those profit margins you only have to sell a few units a year to stay in business....if you operate out of your garage like some people do. Zzzzzzz.

You may be surprised to find that I agree nearly 100% with your opinions on the high end audio business. I just don't see that as being indicative of the state of technical progress.

Unfortunately the market for good value sensibly priced gear has dried up, so I am installing digital theaters and reminiscing about the good old days. Others are trying to sell $150,000 speakers. Gotta make a living.

BTW, what's wrong with Snell AII among other things is that its off axis radiation at around 7-9 Khz is so great compared to its frontal radiation that reflections in that range are louder than the direct field in all but the deadest rooms. That gives it a very interesting and pleasing coloration. Having discovered it purely by accident through experimentation with other speakers I enjoyed listening to it for about a day and then never cared to hear it again. AIIIi does the same thing, it has to do with the polyurethane glued to the front of the tweeter.) Once I knew what it was and how it was done, I lost all interest in owning one. What's interesting about the AR tweeter is that its equivalent could easily be manufactured today simply by changing the geometry of the dome. Nobody cares to because that is not what is in vogue at the moment.

Not aware of this but it sounds interesting. Regarding the ubiquitous 1" dome tweeter of today. I think it became the standard because its bandwidth fits the audio range nicely. It has good axial response to 20kHz and allows easy 2-way systems with typical woofers and a 3k crossover. Power loss in the top Octave; I guess we're all Heathens.

I'm hardly surprised that anoyone in the business of making or selling this stuff would say that pointing out that the emperor has no clothes on is ranting.

I'm guessing that anybody, inside or outside of the industry, would consider your previous post a rant.

David

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QUOTE (speaker dave @ May 28 2010, 04:17 AM) *

Aw, c’mon Dave, give it a shot.

In the meantime, I will:

I think there are several factors at play here, some technical and some emotional....

Steve F.

Hi Steve,

Nothing to quibble with here. I agree with your sentiments.

I think everyone here is a fan of AR. There are just different ideas of how sacred to hold the early designs and published works.

I collect old watches. I'm always amazed that their accuracy is pretty fair considering an all mechanical technology. Their movements are a thing of beauty and craftsmanship. It costs considerably to duplicate their mechanical quality today. And old cameras. They are slow to use but you can get good results: a Tessar or Color Skopar or Sumicron lens is sharp enough for prints of any practical size.

I had an old Corvair 1964 Spyder. The turbocharged one. I remember it as fun to drive and fairly fast. But in the back of my mind I know that if you put one in my driveway tonight, I would discover that it was only fast compared to my wife's slug of an MGB, the handling was treacherous, the seats didn't fit, it was noisy, etc.

If someone tells me they love the sound of their AR3a or 2a, well great! Was it the all time highpoint of speaker design and things were all down hill since then? Really?

David

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You may be surprised to find that I agree nearly 100% with your opinions on the high end audio business. I just don't see that as being indicative of the state of technical progress.

Unfortunately the market for good value sensibly priced gear has dried up, so I am installing digital theaters and reminiscing about the good old days. Others are trying to sell $150,000 speakers. Gotta make a living.

Not aware of this but it sounds interesting. Regarding the ubiquitous 1" dome tweeter of today. I think it became the standard because its bandwidth fits the audio range nicely. It has good axial response to 20kHz and allows easy 2-way systems with typical woofers and a 3k crossover. Power loss in the top Octave; I guess we're all Heathens.

I'm guessing that anybody, inside or outside of the industry, would consider your previous post a rant.

David

The 1" tweeter is ubiquitous because it can be made to have a resonant frequency low enough to match up with a small woofer and handle enough power to provide adequate output at its crossover frequency. If you don't give a hoot about off axis response it doesn't matter. Compared to the AR3a tweeter, the off axis reponse of the typical 1" dome tweeter pure and simple stinks being down about 10 to 15 db at 15 khz 30 to 45 degrees off axis. Small wonder you have to put your ears in a "sweet spot" to hear the highest octave assuming you can still hear those frequencies. AR3a's tweeter was down 5 db at 15 khz 60 degrees off axis by comparison. Even AR's engineers didn't think that was enough, the rationale for the LST and then later Allison's design an expression of that inadequacy. Had dispersion been adequate in their view, it would not have been necessary to go to the expense of building the enclosure with angled panels. That and not a need to compete against Bose 901 was the reason for it IMO, a pair of LSTs costing over twice what 901 cost. This was in keeping with AR's philosophy of maximum dispersion.

The reason most manufacturers do not want to build three way systems is that it would take one more driver and about 3 to 5 more crossover component parts. In AR3a those crossover parts only cost a few dollars even at retail.

It is a sad commentary on manufacturers that they sell speakers costing thousands of dollars and then tell you that you have to buy an additional subwoofer to hear the lowest octave or two of sound. It is an even sadder commentary on the market that willingly buys into it. IMO a speaker system which does not attempt to cover what its maker considers the full audible range of frequencies pertinent to the music it is supposed to reproduce is not selling anything that can legitimately be called a high fidelity loudspeaker system. Like the rest of the system, the manufacturer throws it over the wall and leaves it for the end user to figure out what to do with it.

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Was it the all time highpoint of speaker design and things were all down hill since then? Really?

By whose standards? The modern science of consumer market research began sometime around the 1880's; since then manufacturers in every industry have spent untold person-hours and funds attempting to predict what consumer preferences will be once a product actually hits the shelves, and every industry is littered with the bones of those that didn't "get it right." Is the highpoint of speaker design the high, lofty technological achievement, or the one that sells 500,000 units with a 30% net ROI?

For an individual consumer thinking about buying speakers, it's neither; it's the one that most appeals when the time comes to pull out the checkbook or credit card. So for any number of potential speaker buyers who have not heard anything in 30 years that they found more appealing than their old speakers, be they ARs or JBLs, the answer to your question may very well be "Yes. Really." And then they go spend their money on a trip to a new theme park instead, hopefully one where you have installed something.

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As usual, Zilch, you don't have your facts straight. In 1966 -- just a couple of years after the last AR-3 Live-vs.-Recorded concert you so often malign -- AR had 32.3% commercial-loudspeaker market-share by unit volume. Contrast this with your favorite horn company, JBL: their market share was a paltry 5%. By 1969, second year after the AR-3a was introduced, AR had 27.8%, but JBL had fallen to 3.4%. In 1970, AR had declined to 20%; JBL steady at 3.9%. AR's market-share percentages certainly began to drop in the mid-to-late 80s and into the 90s, but it was still significantly above the west-coast crowd. So let's face it: during the heyday of high fidelity, only west-coast "movie-theatre sound" devotees seemed to be happy with the JBL "horn" sound. True music lovers didn't need their sound punched through a perforated theatre screen. In contrast, the more self-effacing, natural-sound reproduction from ARs, Advents, KLHs and Allisons kept the sales of east-coast, "Massachusetts-style" speakers miles above the harsh-sounding west-coast speaker designs of that period. It wasn’t until the end of high-fidelity sound, as we know it, that JBL made any inroads into the market, and by this time it was probably too late. Fortunately, JBL had Harmon Industries and the professional sound market to keep it afloat. So, Zilch, by denigrating AR's fine reputation you are simply attacking "success." So what's the point?

By the way, I don't think anyone would praise or blame Ken Kantor for the overall fortunes or failures at AR. His contributions were more subtle, and I don't think he affected the sales numbers at AR until the early 1990s with the AR-303 and so forth.

--Tom Tyson

While I agree with you about the poor performance of JBL speakers for accurately reproducing "serious music" I don't think the number of units sold comparison is fair. JBL did not offer anything anywhere near the price of AR4x (or KLH 17.) The least expensive speaker they made as I recall was the L66 Jubal which was I think a 3 way 12" system. I believe it was even more expensive than AR2ax, probably closer in price to AR3/3a. Therefore it would be unreasonable to expect that a highly budget minded segment of the market, the college crowd for example would have been able to consider buying JBL speakers as an alternative to AR. Perhaps someone else has more data on what they offered in that era.

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This was in keeping with AR's philosophy of maximum dispersion.

Careful, now, that's viewed by some here as Zilch patent pejorative. :)

IMO a speaker system which does not attempt to cover what its maker considers the full audible range of frequencies pertinent to the music it is supposed to reproduce is not selling anything that can legitimately be called a high fidelity loudspeaker system.

But that doesn't imply that it must all be in one cab. In fact, distributed bass has been demonstrated to have significant advantage in normalizing the low-frequency wavefield in small spaces. Packaging that and the mid/high drivers separately is an effective approach.

[Not so much if that mid/high comprises a 3.5" driver in a 4" cube, perhaps.... :P ]

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"But that doesn't imply that it must all be in one cab. In fact, distributed bass has been demonstrated to have significant advantage in normalizing the low-frequency wavefield in small spaces. Packaging that and the mid/high drivers separately is an effective approach."

This is quite correct, of course, since the requirements for placement in a room for best bass performance and the placement requirements for optimum mid-high propagation/imaging are often at odds with each other. This is why full-range towers without Allison/AR-9 woofer placement can be tricky.....

Although, TBT, it always seems to be worse in theory than it is in practice. I've usually gotten very good results with full-range speakers exercising common-sense placement practices. Never really thought any of my systems was 'ruined' by the Allison mid-bass floor-bounce dip.

Steve F.

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Although, TBT, it always seems to be worse in theory than it is in practice. I've usually gotten very good results with full-range speakers exercising common-sense placement practices. Never really thought any of my systems was 'ruined' by the Allison mid-bass floor-bounce dip.

Same here.

Does anybody remember, historically, whether the tiny satellite/subwoofer scheme was introduced for home theater or if someone came up with it for music prior to that?

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Same here.

Does anybody remember, historically, whether the tiny satellite/subwoofer scheme was introduced for home theater or if someone came up with it for music prior to that?

The first subwoofer I'm aware of was part of the Infinity Servo-Statik 1 system ($1800) and then the 1A (Around $4000.) It included its own servo amplifier specifically designed for that system. The first satellite sub system I'm aware of came from Cambridge Soundworks. The rest were copycats. Bose was into it early on. There was no home theater in those days, just music and television. Someone familiar with the history of Cambridge might remember when they introduced it, probably sometime in the late 1970s or early 1980s. Home theater came into its own as a result of the VCR which provided audio outputs that could be hooked up to a separate sound system. When stereo and then high fidelity were introduced to VCRs that was a crucial development.

There were early attempts to marry large panel type speakers to woofers, KLH9 and AR1W but the lack of available active crossover networks, equalizers, or other suitable hardware and the high cost of amplifiers and the heat they generated made that impractical. Martin Logan electrostatic hybrids are more successful recent such efforts although IMO it is not a very accurate speaker. The development of efficient inexpensive high powered plate amplifiers with built in crossover networks and equalizers has greatly increased the practicality of subwoofers. Dayton (Parts Express) offers what seems to be a very good one at a reasonable price that can be bought as a kit.

JBL has a video on its web site explaining Toole's findings regarding the optimal number (4) and placement of subwoofers in a room to obtain the most uniform bass response. With very low bass frequencies, even AR9's room response can can change radically when you move just a foot or two closer or further away from a wall. Also moving AR9 just a few inches can radically change the in room system bass response.

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I remember the Infinity and others of its era. But those were intended to to augment fuller-range speakers that usually went down into the 40-60 Hz range on their own. I was thinking specifically of when we first saw the satellite/sub scheme in which the sub takes over everything under 100-200 Hz and the satellites have no woofers at all.

I just looked up the history of Cambridge Soundworks, and it was founded by Henry Kloss in 1988, so if sub/satellites came before that it had to have been by someone else.

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