The best possible replacement tweet

[Guest]

Can anyone tell me, if possible, what the power handling and frequency range specs were for the original 2" tweeter used in the early AR-4x? I've done everything possible to try to have the originals repaired but so far it's been futile as most reapir centers so repairing them "is not worth it. So I'll HAVE to them with the next best thing; using the originals are no longer an option. Has anyone opted for a different model/type/size tweeter while keeping the original crossovers - the universal 8" woofer is offered at Layne Audio for most AR models, so that shouldn't be a problem as a direct replacement.

[ar_pro]

I wonder how one of the Advent tweeters would be in the AR-4...they were pretty effective in the 2-way Advent designs. Another possibility is to wait for an inexpensive pair of 4s on eBay.

[administrator]

I've used a bunch of the new Advent replacement tweeters and I think they would be pretty severe overkill for the AR-4x. The magnets are (relatively) huge and you would have to cut the cabinet. As far as I can tell, the Advent replacements are nice drivers .. but I would look for something less expensive for a 4x replacement.

Mark

[tysontom]

>Can anyone tell me, if possible, what the power handling and

>frequency range specs were for the original 2" tweeter used

>in the early AR-4x? I've done everything possible to try to

>have the originals repaired but so far it's been futile as

>most reapir centers so repairing them "is not worth it. So

>I'll HAVE to them with the next best thing; using the

>originals are no longer an option. Has anyone opted for a

>different model/type/size tweeter while keeping the original

>crossovers - the universal 8" woofer is offered at Layne

>Audio for most AR models, so that shouldn't be a problem as

>a direct replacement.

The power-handling capability of the AR-4x is such that it will handle the unclipped power of most amplifiers designed for home-use, playing music or normal program material. This means that the speaker will handle clean peaks of probably 150 to 200 watts, but amplifiers of 30-60 watts-per-channel are well suited to this speaker.

The AR-4x, both throughout the bass, midrange and treble, was smooth and flat for a small, inexpensive loudspeaker. It is at least as good as, and perhaps better than, anything anywhere near its low price. And once again, in the mid-60s CU (Consumer Reports) wrote that the AR-4x's tweeter handled the upper ranges better than any other speaker ever put through their labs, no matter how big or expensive.

The best bet for the 2-1/2" AR-4x tweeter is to replace it with original NOS tweeters, rather than retrofit them with an alternative tweeter. I realize that this sounds difficult and may seem daunting, but there are many AR-4x's out there in the world -- many hundreds-of-thousands of AR-4x's were made, so I have to think that somewhere out there you should be able to find another pair and cannibalize the best drivers from all of them you can find. And these old speakers should be available at relatively low cost.

Retrofitting the woofer and tweeter with new-style or different drivers will create a speaker that will put out sounds, alright, but it may or may not sound as smooth and accurate as the original-driver AR-4x's. What made the original AR-4x so good was the accuracy and low distortion AR designed into this little inexpensive loudspeaker -- it was quite an achievement.

--Tom Tyson

[Guest]

I've thought about trying to locate another pair of 4x speakers - maybe at a garage sale, flea market, etc. If that's not an option that presents itself easily does anyone know of any particular make/model that they have found to be sonically compatible and acceptable? Like the tweeter (#12000060) mentioned in the past at AB Tech. I'm not giving up on looking just yet, but I may eventually have to put some sort of quality replacement tweeter in a walnut cabinet that has been refinished to perfect condition!

Layne Audio's website says, regarding the AR-4x model, that "replacement can easily be achieved by substituting the orignal tweeters with dome-style tweeters to provide much better sound" and that "the 2" cone tweeter, used in most models, was crossed over way too low, at 1200 HZ, so failure is common."

If anyone has any other recommendations please feel free to do so. And thanks Tom for providing me with some great information about these classic AR-4x speakers!

[tysontom]

>I've thought about trying to locate another pair of 4x

>speakers - maybe at a garage sale, flea market, etc. If

>that's not an option that presents itself easily does anyone

>know of any particular make/model that they have found to be

>sonically compatible and acceptable? Like the tweeter

>(#12000060) mentioned in the past at AB Tech. I'm not giving

>up on looking just yet, but I may eventually have to put

>some sort of quality replacement tweeter in a walnut cabinet

>that has been refinished to perfect condition!

>

>Layne Audio's website says, regarding the AR-4x model, that

>"replacement can easily be achieved by substituting the

>orignal tweeters with dome-style tweeters to provide much

>better sound" and that "the 2" cone tweeter, used in most

>models, was crossed over way too low, at 1200 HZ, so failure

>is common."

>

To each his own, but I definitely disagree that substituting original with dome tweeters will provide better sound in the AR-4x. It will give it much greater output, brighter sound, etc., but that does not make it better. Remember: the balance of the speaker is important, the relation of the woofer to the midrange. There is some disagreement regarding the crossover. AR's technical data suggests a 1000 Hz. crossover, yet the Hirsch-Houck review stated 1200 Hz. In any event, it is academic: the lower the crossover, the better! It means that the woofer is not getting up into the midrange-treble area where it cannot respond cleanly, and the woofer has poor dispersion. AR always tried to get the woofer crossed over as low as possible, and the 2-1/2-inch tweeter was very capable at these frequencies. The power-handling for this speaker was just fine for a small, two-way speaker. AR did not have problems with tweeter burnouts any more with this speaker than with any other system, and usually the problems were with people over-driving their speakers, or due to amplifiers going into overload or clipping.

>If anyone has any other recommendations please feel free to

>do so. And thanks Tom for providing me with some great

>information about these classic AR-4x speakers!

I noticed a pair of AR-4x's for sale on e-Bay:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewI...item=1391853841

If you could get these cheap enough, you could get the best drivers from the combination of four speakers and end up with a fine, original pair of AR-4x's!

--Tom Tyson

[Steve F]

Remember: the

>balance of the speaker is important, the relation of the

>woofer to the midrange. There is some disagreement

>regarding the crossover. AR's technical data suggests a

>1000 Hz. crossover, yet the Hirsch-Houck review stated 1200

>Hz. In any event, it is academic: the lower the crossover,

>the better! It means that the woofer is not getting up into

>the midrange-treble area where it cannot respond cleanly,

>and the woofer has poor dispersion. AR always tried to get

>the woofer crossed over as low as possible, and the

>2-1/2-inch tweeter was very capable at these frequencies.

>The power-handling for this speaker was just fine for a

>small, two-way speaker. AR did not have problems with

>tweeter burnouts any more with this speaker than with any

>other system, and usually the problems were with people

>over-driving their speakers, or due to amplifiers going into

>overload or clipping.

>--Tom Tyson

I agree completely with Tom's position. If non-original tweeters are used, you'll have a speaker, but it won't be an AR-4x.

The 1968/9 brochure (the one with that introduced the AR-5, and pictured it in pre-production form with a side-by-side midrange and tweeter), as well as the later 1971 brochure (Von Karajan/Ellis 3a, Fiedler 5, NY studio 2ax, Judy Collins 4x) both stated the 4x's crossover as 1200Hz.

When I was a teenager in the mid-60's, my father bought 4x's to replace his floorstanding 15" Goodmans three-ways. The 4's were astonishingly superior in every way--deeper, smoother, more natural, more musical. The 4x established a standard of high performance for "small" speakers that was far beyond anything that came before it, and went a long way to making truly superb stereo sound available to a wide audience, without overwhelming the listening room with large boxes.

Our system was powered by a Sherwood S7900 receiver, conservatively rated at 60w RMS per channel. Our 4's worked flawlessly for years, without ever blowing a tweeter.

Remember also, AR-2x's--that's 2x, NOT 2ax-- made after 1970 (with the new red-lettered "AR-2x" logo) used the same 2 1/2" tweeter as the 4x, so if you could find a pair of those, you'd have your replacement tweeters.

Steve F.

[Guest]

Yeah, I guess everyone is pretty much correct regarding my keeping the speakers as original as possible....Hell, if I waited this long I could wait a little longer right? In the meantime, I'm thinking about paoosibly contacting AB Tech (AR's recognized affiliate forold and new speaker parts) to see if they have anything suitable for this model as I seem to recall someone mentioning P/N#12000060 - a 2.5" tweeter - as a suitable replacement. Fortunately, the original 8" woofer can be easily reconed or replaced for this model. These tweeters, though, are a real pain in the ass though!

[Carlspeak]

I'd like to add a qualifed dissenting comment to the discussion. By qualified I mean that if, and only if, you want to retain that 'original' AR4 sound, by all means find that 2" original tweeter and pop it in. However, if you want the truly best possible replacement tweeter with superior sonics, detail and air, then I also feel as one of the previous responders recommended, that you should get a good quality dome tweeter and cross it over in the 2-3 kHz region for the followng reasons:

1) I don't understand the reasoning for putting 95% of the sonic workload on the poor tweeter in favor of not 'overworking'that precious woofer. If you xover at 1 kHz, then the remaining 19 kHz of the useful sonic spectrum is carried by the tweeter. Check out the woofer and make sure it doesn't start to roll off at 1 kHz. Most two way woofers can go to 3-4 kHz before they fall off.

2) If those 2" or so cone tweeters were so good, why aren't they in common use today? Instead, the superior 2-way speakers being built and sold today use dome or ribbon tweeters crossed over in the 2-3 kHz region.

3) While your at it, buy top quality mettalized polypropylene caps for the tweeter, whichever one you choose. Check out North Creek. They offer some of the best audiophile caps and resistors available today. If you go for that dome tweeter don't worry about it overpowering the woofer. You can pad it with a good quality, non-inductive resistor so it's output spl closely matches the woofer. f your not sure what value to choose, I can help with that. However, don't buy one of the cheap l-pads and try to "tune" the tweeter. The sonics you paid for in the tweeter will be lost in the sliding wiper mechanism of l-pad.

Good luck whichever way you decide to go with your tweeter replacement decision.

Carl, The SpeakerDoctor

[tysontom]

>I'd like to add a qualifed dissenting comment to the

>discussion. By qualified I mean that if, and only if, you

>want to retain that 'original' AR4 sound, by all means find

>that 2" original tweeter and pop it in. However, if you want

>the truly best possible replacement tweeter with superior

>sonics, detail and air, then I also feel as one of the

>previous responders recommended, that you should get a good

>quality dome tweeter and cross it over in the 2-3 kHz

Dear Carl, The SpeakerDoctor,

First of all, I think it is great to have diverse opinions (qualified or unqualified) on these subjects, and certainly no one answer is the only answer. Discussions such as these are very important to these forums. Furthermore, it is not dissenting to dissagree, even if you are wrong.

There might be a rationale in retrofitting the original 2-1/2-inch cone tweeter with a new dome tweeter, if one is looking to change the sound. Like every loudspeaker ever made, the AR-4x was by no means perfect, and it could always use improvements. Yet to change the tweeter and still maintain the proper spectral balance and to do it right, you would need to re-design the crossover completely, and you would need the resources of an anechoic chamber, lots of test equipment and so forth. Hell, why not just get some plans from AudioXpress or Joe D'Appolito or someone, and build one from scratch? This way, you could possibly build a great little speaker that would have the proper spectral balance, and you would not have to measure all the parameters of the old AR woofer, cabinet, etc. All those details for a kit speaker would be available with the drawings and plans supplied.

When AR introduced the AR-4x in 1965, they were not looking for "superior sonics, detail and air." I don't think those descriptions existed then. AR was looking for sonic accuracy, "high-fidelity" sound and the best means to achieve this within the 1965 state-of-the-art of the $57 selling price. For my money, I would take "accuracy" any day over "detail and air," but this is my viewpoint. Maybe I'm wrong, but I think the reason for high-fidelity sound reproduction is to recreate, as closely as possible, the original sound, not to create a new experience. After all, that is the definition of "high fidelity."

There were dome tweeters -- pioneered in the AR-3 -- in existence when the AR-4x was introduced, but cost for dome tweeters was prohibitive, of course, and AR needed to find an alternative. The little AR-designed-and-built 2-1/2-inch cone tweeter was a special design, and it was treated and "worked over" until AR was able to achiever virtually flat (actually slightly rising) response right out to 20 kHz., and off-axis response was excellent, too, for a cone driver. At 15 kHz., and 30-degrees off axis, the tweeter was only about 6 or 7 dB down! This would be good performance for any tweeter. The most important thing was that the tweeter had unusually smooth and uniform response, a hallmark of accuracy.

>region for the followng reasons:

>1) I don't understand the reasoning for putting 95% of the

>sonic workload on the poor tweeter in favor of not

>'overworking'that precious woofer. If you xover at 1 kHz,

>then the remaining 19 kHz of the useful sonic spectrum is

>carried by the tweeter. Check out the woofer and make sure

>it doesn't start to roll off at 1 kHz. Most two way woofers

>can go to 3-4 kHz before they fall off.

Well, first of all, you are by no means putting 95% of the sonic workload on the "poor tweeter" by crossing it over at 1000 or 1200 Hz. It's not as if the tweeter must carry 95% of the amplifier power -- nothing of the kind. Most of the current goes to the woofer, as this is where most of the air is moved. A lower crossover -- e.g., 1200 Hz. vs. 3,000 or 4,000 Hz -- means that the tweeter can reproduce sounds that are uniformly dispersed. Yes, the power-handling capability of the AR-4x is reduced somewhat by the lower crossover, but the AR-4x was not meant to be a public-address speaker, so you cannot bring down the house with the speaker. It gives up very little, however, for use as a home-type music loudspeaker. On the other hand, all eight-inch woofers become directional up around 3-4 kHz., and the AR-4x woofer's response becomes fairly ratty (breakup modes) above 1 kHz. even on axis. This ragged response is "coloration," pure and simple. Also, an eight-inch woofer designed to work well down into the relatively deep bass -- and the AR-4x is flat down to about 60 Hz. and down only 12 dB around 32 Hz. -- usually cannot continue to respond well in the higher frequencies. It's a trade off. Certainly, more modern woofers can do a better job at this compromise.

>2) If those 2" or so cone tweeters were so good, why aren't

>they in common use today? Instead, the superior 2-way

>speakers being built and sold today use dome or ribbon

>tweeters crossed over in the 2-3 kHz region.

>Carl, The SpeakerDoctor

Since the AR-4x was designed, there have obviously been great advances in driver design, materials, etc. AR would surely have used a dome back then if it could be done within the limitations of cost constraints.

In the end, however, wouldn't it just be cheaper to just go out and build a brand-new kit speaker with all the special polypropylene caps, dome tweeters, etc.? By the time you replaced all that stuff in a 37-year-old AR-4x, you could probably save money by building a new kit speaker from scratch. I don't mean to make the AR-4x seem like it is a sacred cow or something, but the reality is that it was good enough originally to warrant rebuilding as new, rather than trying to re-invent the wheel. The old AR-4x parts are out there, and can be found. Yet to redesign the AR-4x, one would have to have access to anechoic chambers, the necessary test equipment -- let alone engineering knowledge -- and so forth to retrofit the drivers with different designs and have it sound balanced and accurate.

--Tom Tyson

[ar_pro]

This is exactly to the point...is the idea to rebuild & restore a classic, or use it as the foundation for an "improved" (read: different) loudspeaker? Whatever remains after installing a new dome tweeter is no longer an AR-4, right?

[Guest]

Man, what did I start here? Just to lighten things up a little bit, I had the opportunity of speaking to an elderly gentleman named Louis Gerring this morning who once was part owner of a "hifi shop" in NYC in the 1950s and 1960s. He told me that he delivered a pair of early original ARs from his shop on a hand-truck to a musician about seven blocks away - "A skinny kid who I thought was Dave Brubeck at first... He lived on the fourth floor over at the Brevoort over by Washington Square...This was right before Christmas 1958." As it turned out, this "skinny kid" was the late Buddy Holly (he didn't know who Buddy Holly was until he died a few months later, but he said the singer gave him a $20 tip which was quite a bit of money back in 1958 and thought he still had the AR delivery receipt somewhere in his files). Back to the point of AR4x speakers: He did mention (after I told him I was trying to restore an old pair odf AR4x models and trying to ocate some original tweeters) that the AR4 and 4x were pretty controversial because of its size, sound, and speaker choices even when it was in its introductory years. He said that the AR4 and AR4x were "the speaker of choice to own for college kids in their dorm rooms in the 1960s...Most of the people we sold them to were college kids here in the city and over at Columbia...Couldn't stock enough of those little bastards back then."

Obviously these AR4x speakers are still controversial due to their size, sound, and speaker choices (as I'm finding out). I didn't mean to cause such extensive discussion about these particular AR speakers, but if they were as popular as it seems by all these posts I am learning more than I thought I would! After all I only wanted to know about tweeter replacement, but now that I heard most of the discussions I'm intent on keeping these AR4x original as I've located a pair someone is willing to sell off due to below standard cabinet conditions. However, AB Tech has informed me that they do carry replacements for the AR4x models. I was wondering if anyone has used these replacements or knows anything about them as I was informed that they were compatible with the original 8" inch woofer and 4x crossover design. I hope so as I'm going to give them a try while also grabbing those other 4x speakers I located just in case!

[Steve F]

>>1) I don't understand the reasoning for putting 95% of the

>>sonic workload on the poor tweeter in favor of not

>>'overworking'that precious woofer. If you xover at 1 kHz,

>>then the remaining 19 kHz of the useful sonic spectrum is

>>carried by the tweeter. Check out the woofer and make sure

>>it doesn't start to roll off at 1 kHz. Most two way woofers

>>can go to 3-4 kHz before they fall off.

>Well, first of all, you are by no means putting 95% of the

>sonic workload on the "poor tweeter" by crossing it over at

>1000 or 1200 Hz. It's not as if the tweeter must carry 95%

>of the amplifier power -- nothing of the kind. Most of the

>current goes to the woofer, as this is where most of the air

>is moved. A lower crossover -- e.g., 1200 Hz. vs. 3,000 or

>4,000 Hz -- means that the tweeter can reproduce sounds that

>are uniformly dispersed. Yes, the power-handling capability

>of the AR-4x is reduced somewhat by the lower crossover, but

>the AR-4x was not meant to be a public-address speaker, so

>you cannot bring down the house with the speaker. It gives

>up very little, however, for use as a home-type music

>loudspeaker. On the other hand, all eight-inch woofers

>become directional up around 3-4 kHz., and the AR-4x

>woofer's response becomes fairly ratty (breakup modes) above

>1 kHz. even on axis. This ragged response is "coloration,"

>pure and simple.

>

>--Tom Tyson

Tom is quite correct here. We do not hear in a linear-frequency fashion; instead, we respond to the sonic spectrum in octaves. There are roughly 10 audible octaves spanning from 20-20,000 Hertz (“Hz”), or as they were formerly called “cycles per second” (CPS). Each octave (a musical octave, as in “doe, ray, me, fah, so, la, ti, doe”) is a doubling or halving of frequencies. So 20-40Hz is an octave, 40-80, 80-160, 160-320, 320-640, 640-1280, etc.

So as you can see, the AR4x woofer crossing over at 1200Hz, far from only handling “5% of the sonic workload” as someone mentioned earlier, is actually handling almost 6 of the 10 audible octaves, or SIXTY PERCENT of the “sonic workload.”

Drivers become directional (their dispersion narrows) with increasing frequency. When the wavelength of the frequency being reproduced is longer than the effective radiating diameter of the driver, the driver will tend to “beam” that frequency straight ahead, like a flashlight beam, instead of dispersing it widely in all directions.

There is a formula for determining at what frequency directionality becomes a problem: take the number 13560 and divide by the frequency. The answer gives you the wavelength in inches of that frequency. Compare that to the diameter of the driver, and you’ll see whether or not that driver will have wide dispersion up to that frequency.

For example, let’s say a two-way speaker with an 8” woofer crosses over to the tweeter at 2500Hz. Divide 13560 by 2500 and you get 5.424 inches. So, no, an 8” woofer will not disperse widely to 2500Hz. A little reverse 9th-grade algebra, and presto! We find out an 8” woofer is good only to about 1695Hz. AR understood this, and made the correct design decision to engineer a tweeter that could extend low enough in frequency, and cross over before the woofer became directional. The AR-4x’s design ensures a wide, uniformly-dispersed midrange that translates into smooth, accurate sound for listeners seated at different locations around the room. That was their goal. The goal of a tightly-focused “soundstage” (whatever that inexact, ethereal term is supposed to mean), where only one listener is in the sweet spot, is accomplished with a different speaker designed to achieve a completely different result.

So it turns out that the “popular advice” by the Johnny-come-lately’s to cross over the AR-4x at 3 or 4000Hz is not such good advice after all, if the objective is to preserve the 4x’s design intent.

Steve F.

[Carlspeak]

>

>>>1) I don't understand the reasoning for putting 95% of the

>>>sonic workload on the poor tweeter in favor of not

>>>'overworking'that precious woofer. If you xover at 1 kHz,

>>>then the remaining 19 kHz of the useful sonic spectrum is

>>>carried by the tweeter. Check out the woofer and make sure

>>>it doesn't start to roll off at 1 kHz. Most two way woofers

>>>can go to 3-4 kHz before they fall off.

>

>Wow! looks like I really stirred up a hornets nest! Haven't seen this many postings on a subject in a while! Anthony V was right: lighten up guys. I was just trying to help him find the best tweeter and wish him well in his quest for a suitable replacement cone tweeter in the 2 to 2 1/2 in range now that he has made his choice. I certanly learned a lesson on where the priorities lie here in the classic discussion area: the gear comes first and the music comes second. Listening to all the excellently recorded music of today with a 60's or 70's vintage speaker is (to me) depriving oneslelf of all the detail and nuance in those great recordings. So be it.

>>Well, first of all, you are by no means putting 95% of the

>>sonic workload on the "poor tweeter" by crossing it over at

>>1000 or 1200 Hz. It's not as if the tweeter must carry 95%

>>of the amplifier power -- nothing of the kind.

You're right about the amplifier power. However, that isn't what I was referring to. Maybe I should have writtn frequency band workload. And dividing up the sonic spectrum into octaves is nice but we don't listen in octaves. We listen to a continum of the frequency spectrum.

Most of the current goes to the woofer, as this is where most of the air

>>is moved. A lower crossover -- e.g., 1200 Hz. vs. 3,000 or

>>4,000 Hz -- means that the tweeter can reproduce sounds that

>>are uniformly dispersed. Yes, the power-handling capability

>>of the AR-4x is reduced somewhat by the lower crossover, but

>>the AR-4x was not meant to be a public-address speaker, so

>>you cannot bring down the house with the speaker. It gives

>>up very little, however, for use as a home-type music

>>loudspeaker. On the other hand, all eight-inch woofers

>>become directional up around 3-4 kHz., and the AR-4x

>>woofer's response becomes fairly ratty (breakup modes) above

>>1 kHz. even on axis. This ragged response is "coloration,"

>>pure and simple.

>>

>>--Tom Tyson

>

>

>Tom is quite correct here. We do not hear in a

>linear-frequency fashion; instead, we respond to the sonic

>spectrum in octaves. There are roughly 10 audible octaves

>spanning from 20-20,000 Hertz (“Hz”), or as they were

>formerly called “cycles per second” (CPS). Each octave (a

>musical octave, as in “doe, ray, me, fah, so, la, ti, doe”)

>is a doubling or halving of frequencies. So 20-40Hz is an

>octave, 40-80, 80-160, 160-320, 320-640, 640-1280, etc.

>

>So as you can see, the AR4x woofer crossing over at 1200Hz,

>far from only handling “5% of the sonic workload” as someone

>mentioned earlier, is actually handling almost 6 of the 10

>audible octaves, or SIXTY PERCENT of the “sonic workload.”

>

>Drivers become directional (their dispersion narrows) with

>increasing frequency. When the wavelength of the frequency

>being reproduced is longer than the effective radiating

>diameter of the driver, the driver will tend to “beam” that

>frequency straight ahead, like a flashlight beam, instead of

>dispersing it widely in all directions.

>

> There is a formula for determining at what frequency

>directionality becomes a problem: take the number 13560 and

>divide by the frequency. The answer gives you the wavelength

>in inches of that frequency. Compare that to the diameter of

>the driver, and you’ll see whether or not that driver will

>have wide dispersion up to that frequency.

>

>For example, let’s say a two-way speaker with an 8” woofer

>crosses over to the tweeter at 2500Hz. Divide 13560 by 2500

>and you get 5.424 inches. So, no, an 8” woofer will not

>disperse widely to 2500Hz. A little reverse 9th-grade

>algebra, and presto! We find out an 8” woofer is good only

>to about 1695Hz.

So, what are you telling me Steve, that the 2" tweeter will only be good to about 6780 Hz? What's good for the goose isn't good for the gander?

AR understood this, and made the correct

>design decision to engineer a tweeter that could extend low

>enough in frequency, and cross over before the woofer became

>directional. The AR-4x’s design ensures a wide,

>uniformly-dispersed midrange that translates into smooth,

>accurate sound for listeners seated at different locations

>around the room. That was their goal. The goal of a

>tightly-focused “soundstage” (whatever that inexact,

>ethereal term is supposed to mean), where only one listener

>is in the sweet spot, is accomplished with a different

>speaker designed to achieve a completely different result.

>

>So it turns out that the “popular advice” by the

>Johnny-come-lately’s to cross over the AR-4x at 3 or 4000Hz

>is not such good advice after all, if the objective is to

>preserve the 4x’s design intent.

Remember guys - it's the music that counts, not the gear. The great music of the world will endure long after all the AR's and KLH's have been relageted to the cellar or elsewhere.

>

>Steve F.

[Steve F]

>>>>1) I don't understand the reasoning for putting 95% of the

>>>>sonic workload on the poor tweeter in favor of not

>>>>'overworking'that precious woofer. If you xover at 1 kHz,

>>>>then the remaining 19 kHz of the useful sonic spectrum is

>>>>carried by the tweeter.

I certanly learned a lesson on where the priorities lie here in the classic discussion area: the gear comes first and the music comes second.

And dividing up the sonic spectrum

>into octaves is nice but we don't listen in octaves. We

>listen to a continum of the frequency spectrum.

Actually, we DO listen in octaves, whether or not that information seems non-intuitive. It's simply the way the human auditory brain-ear system processes sound. It's not me saying it, and it's not my opinion. Dust off your first-year college acoustics textbook. There it is. That's what audio engineers mean when they talk about "octave to octave balance." The distance between 200-400Hz is the same to the ear as the distance between 5000 and 10000Hz. They're both an octave apart. That's just how humans hear.

As far as old equipment is concerned, I think ar_pro had it exactly right when he said, "the idea to rebuild & restore a classic."

I love music, AND I enjoy old, classic audio equipment. The two interests are independent of each other, and speaking for other Forum members, interest in one does not preclude or diminish interest in the other.

There is no representation on this site that a 1960's-vintage speaker is always superior to the best of today's equipment. But some of the older speakers were actually better than their designers realized at the time, and with modern, well-recorded music, an old speaker--correctly, painstakingly engineered and assembled with an eye to craftsmanship that is often lacking today--can sound surprisingly good.

Studying about those old products and restoring them as closely to original as possible is a great, satisfying hobby.

Regarding AR's engineering design choices, they always aimed for smooth energy response at the listening position. This design direction dictated, among many other things, as low a woofer to midrange crossover (in a three-way) or woofer to tweeter crossover (in a two way) as practical, within the normal constraints of good engineering practice, usability/reliability, and project budget targets.

If you look at AR's woofer to tweeter crossover frequencies in their two-way speakers, they're consistently lower than most of today's two-way speakers. AR believed in wide, even midrange dispersion, and the low crossover accomplished that goal:

AR-2 2000Hz

AR-2x 2000Hz

AR-2x (after 1970)1200Hz

AR-4 2000Hz

AR-4x 1200Hz

AR-6 1500Hz (first production)

AR-6 1800Hz (later production)

AR-7 2000Hz

Has the speaker art advanced in the last 40 years? Of course. Do you have to prefer the way old AR speakers sound compared to your favorite speaker from today? Of course not.

Simply recognize that there was something special about the speakers from that era that all of us Forum members--Tom, Toasted, Charger, ar_pro, Anthony, Dale, and the rest of us-- find fascinating.

Steve F.

[ar_pro]

>Simply recognize that there was something special about the

>speakers from that era that all of us Forum members--Tom,

>Toasted, Charger, ar_pro, Anthony, Dale, and the rest of

>us-- find fascinating.

>

>Steve F.

A fine letter, with many accurate observations. I initially encountered Acoustic Research products when I was a college freshman (1968), listening to hifi systems in my friends' homes. These setups were invariably assembled by their no-nonsense fathers, and primarily consisted of AR (speakers & turntables), Dynaco, McIntosh, and Shure. In retrospect, there was just something RIGHT about these companies and their products - even the high-end Mac equipment was within the reach of most budgets (people actually saved up for things then), and the Dyna stuff provided maximum value for the money, with superb performance available at kit prices. My first AR product was the turntable, followed by a single AR-2ax (an orphan that was purchased from a Radio Shack sales floor for $50) - six months later, I shoulder-carried its brand-new partner 8 city blocks through the snow to the closest bus stop. And when my little Lafayette amplifier took out the tweeters, a drive to NYC's ancient Cortlandt Street (where the new WTC was going up) produced same-day repair from the authorized AR service center...the technician even took it upon himself to provide a new pair of matching brass emblems for my speakers, as the orphan was previously without a nameplate. There really was "something special" about AR products and customer service then - certainly special enough to make that college kid a life-long fan!

[Guest]

Correct me if I'm wrong, but wasn't the area used to build the World Trade Center well known as an electronics district in NYC years ago? Where, in NYC, would someone be likely to find some vintage audio parts and components today?