70 replies to this topic

[Steve F]

Although I basically agree with Tom here, I’d like to look at things from a slightly different perspective.

It’s easy to fall into the trap of thinking all loudspeaker/acoustic knowledge/experience has existed all along, and to the same degree. So it’s very natural to simply pose the question “Couldn’t AR just tell from their measurements?” and equally natural to simply answer, “AR understood this phenomenon but had a different design philosophy at that time….”

I would offer for consideration the distinct possibility that AR did not fully appreciate the significance of driver interference and cabinet diffraction in the early-to-mid ‘60’s. (That was when the 2ax-3a-5 were designed. They may have appeared on the market in the late 60’s, but they were designed in the mid ‘60’s.)

I would say that the 3a’s drivers were mounted as they were—diagonally staggered—as much for mechanical/fitting convenience as any other reason. That the interference/radiation pattern was nearly the same horizontally as vertically was a coincidence, not a design goal. If it were a design goal, then the 2ax would have been that way also. It wasn’t.

AR continued to demonstrate that they didn’t consider it to be of significance right through the 10 Pi-11-12 ADD models. Those had their mids and tweets mounted all “wrong”—side by side, a la the 2ax—even though their cabinets were cosmetically intended, unambiguously, to be vertical, with that walnut trim strip at the bottom of the 11-12 (the door at the top of the 10 Pi) going side-to-side.

I submit that the 9 and the Vertical Series was not as much a simple “change of heart” by AR as it was a new awareness of that vertical mounting/interference design aspect—an awareness that simply didn’t exist to anywhere near that degree (if at all) in the mid-‘60’s. With the Verticals, AR finally realized that, yes, you could have wide dispersion, excellent far-field power response AND clear, almost interference-free near-field response, all at the same time.

That knowledge didn’t exist in 1965 the way it did in 1977. The collective understanding in any field advances with time, and as observers after the fact, we all tend to compress that in retrospect.

Steve F.

[michiganpat]

could be very true, that the knowledge wasn't there, and it might not have been there just because at the time imaging wasn't a big deal or even a consideration; soundstage and spaciousness were, which the driver placement of the 2 & 3 series, from what I've read at least, may have had some advantages...heck, through the mid 60's (when the classic AR's were designed), the bulk of popular recordings were still primarily mixed in mono..reading interviews with George Martin & Paul McCartney, they spent a lot more time mixing the mono mix of the beatles early albums, and the stereo mix was a real afterthought (obvious in listening to a lot of the stereo mix of early recordings, where you'll hear stuff like paul's voice out of the right speaker, and his bass out of the left

[RoyC]

Your comment about the 303 vs. the 11 is interesting. In what ways did you prefer the 303?
Steve F.

Well, it was only a brief comparison, and by no means scientific. The unanimous impression among 3 of us was that the 303 had a smoother, more open, response through the midrange, especially noticeable with vocals. We preferred the 303's deep bass response slightly as well. The 303 woofer has a rubber surround, and is a close cousin to the wonderful NHT 1259 12 inch woofer. It should be noted that its woofer has the advantage of operating in a slightly larger cabinet. The AR-11 did have the advantage of level controls, and the 303 had none...which brings me back to the question: Did the AR-58 series have level controls?

Perhaps the 58 could match the smoother midrange of the 303, but I would be very surprised if it could match the bass response. I have mixed, matched, and measured all of the various versions of the AR 12 inch woofer, and have never found the AR-9, nor the later Tonegen woofer, to be the equal of the earlier iterations with regard to bass response (in a 3a size cabinet). The AR-9 and Tonegen woofer, however, both reach further into the midrange, which may contribute to an improvement in that regard. Whether by design or not, Q of .5 or .6 is quite low, and in my experience will not provide the subjective reverberant bass response associated with earlier AR speakers. In the AR-9 era, AR had much larger speakers with greater bass response, so could it be that this was not a priority for the AR-58?

It is interesting that the mirror-imaged AR 303 had the tweeter and midrange vertically placed, but they were offset relative to the woofer. There is a school of thought that believes this arrangement is preferable to having the high range drivers equidistant from the baffle edges.

Roy

[mluong303]

Hi Steve

The reason for AR-58s crossover point set at 700Hz was due to the limitation of the AR-58s midrange which has Fs of 604Hz in comparison to the AR-3a/AR-11 midrange that has Fs of 485Hz so you can push it down to 525Hz crossover point still be OK.

AR-3a Improved and AR-11 sound much closer to the original AR-3a with foam surround woofer than AR-58s. So don't rush out to find a pair of AR-58s and hope for it to out do the AR-3a sound. You will be disappointed! Personally I love the AR-58s for it represents the end era of the AR-3a family. Its vertical driver arrangement made more sense to me than the classic AR-3a or AR-10Pie/AR-11 look. I never listen to my AR speakers placed horizontally and certainly not shove them into bookshelf by any mean. I also like the 58Bx and 58Bxi because these two models sound very good with Japanese receivers from Marantz, Sansui and Pioneer. 100w/ch of Japanese receiver power will made these speakers sound wonderful and for how much they cost as AR speakers, I don't mind the walnut vinyl covered MDF cabinets! The 12" woofer AR bass was there up close... These are my personal feeling and listening experience and by the way I am a real AR fanatic so I may be bias without realizing it! To me AR speakers carry a very unique sound quality of its own. Once you learn to love it then you will have a difficult time to pull yourself off from that addiction. I enjoy all of the AR speakers I owned no matter they are the most expensive AR Limited 3 speaker system or the tiny little AR-18s that sound wonderful with 65w/ch Sony receiver...

AR-58s has different crossover from AR-91. AR-58s crossover has no switches while AR-91 has switches for mid and high range drivers.

Minh Luong

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[RoyC]

The reason for AR-58s crossover point set at 700Hz was due to the limitation of the AR-58s midrange which has Fs of 604Hz in comparison to the AR-3a/AR-11 midrange that has Fs of 485Hz so you can push it down to 525Hz crossover point still be OK.
Minh Luong

Hi Minh,

Good info! It dovetails with my observation that the unfiltered response of the later AR 12 inch woofer had more extension into the midrange. This would make the higher crossover point of the AR-58 a bit easier to achieve.

It would certainly be fun to line them all up next to each other for us to listen and discuss.

Roy

[Robert_S]

Without having seen the actual schematics, I'd be willing to venture a guess and say that the 58s's x-o was exactly the same as the 91's, given both speakers' use of the exact same drivers and having the same x-o frequencies. It's my impression that the 91 represented AR's very best efforts at a 12" 3-way crossover in 1979, so I have no reason to think that the 58s's x-o would be anything less. "Off the shelf" does not necessarily mean "inferior."

Interesting discussion, and a guess not too far wide of the mark.



The AR-58s shared a crossover design with the AR-915, which was essentially an AR-91 without level controls in a cabinet similar to the AR-92 (as in no beveled edges). The AR-915 cabinet was available in either furniture-grade oiled-walnut veneer, or vinyl finish.

The following engineering file reveals the crossover detail:

 AR-Drawing469 - AR-58s, -915, -915 veneer Crossover.pdf   796.73K   250 downloads

Robert_S

[mluong303]

Thank you Robert_S for pointing out this information. Does the AR-915 use the AR-9 midrange or the AR-58s midrange? If you could verify the midrange part number on the 915 that would be great.

Minh Luong

[Steve F]

Interesting discussion, and a guess not too far wide of the mark.



The AR-58s shared a crossover design with the AR-915, which was essentially an AR-91 without level controls in a cabinet similar to the AR-92 (as in no beveled edges). The AR-915 cabinet was available in either furniture-grade oiled-walnut veneer, or vinyl.

The following engineering file reveals the crossover detail:

 AR-Drawing469 - AR-58s, -915, -915 veneer Crossover.pdf   796.73K   250 downloads

Robert_S

Exactly as I thought. Thanks for the confirmation on the 58s crossover.

Posted Yesterday, 11:08 PM
Hi Steve

The reason for AR-58s crossover point set at 700Hz was due to the limitation of the AR-58s midrange which has Fs of 604Hz in comparison to the AR-3a/AR-11 midrange that has Fs of 485Hz so you can push it down to 525Hz crossover point still be OK.

Minh Luong

This is fascinating, because AR did this consistently in the 'old days.' These days the 'rule of thumb' states "an octave above resonance, minimum." So, if a driver has an Fs of 500Hz, 1000Hz should be the minimum crossover frequency, for matters of power handling, distortion, etc. AR used to drive the heck out of their drivers, which may expain why so many failed.

Minh, I wonder if you could give us a brief impression of the Limited 3.

In 1992, I visited the AR factory in Canton MA with the BAS, right around the time of the Limited Series intro. John Buzzota was the engineer on the 3 speaker. Dave Cahill, later the head transducer engineer at BA, was the driver guy. I remember talking to Cahill when he was at BA and he said that the upper brass at AR wanted to use this high-end, prestigious tweeter in the 3 (I think it was a Scan-Speak). But a lower-cost Vifa actually performed much better.

No, the upper brass would have none of that garden-variety Vifa; only the Scan-Speak would do. Cahill muttered to me that they had to re-do the crossover completely, adding traps and filters, to get the HF response with the Scan-Speak to equal what they had achieved with the Vifa and a much simpler, less costly network. This is often how it is in the real world, everyone.

Still, the Limited 3 was an impressive speaker. I heard it there at AR and again at CES, and I liked it. I'd love to hear a more detailed, longer-term assessment.

Steve F.

[Robert_S]

Thank you Robert_S for pointing out this information. Does the AR-915 use the AR-9 midrange or the AR-58s midrange? If you could verify the midrange part number on the 915 that would be great.

Minh Luong

Hi Minh,

The AR-915 used the same midrange unit as the AR-91, -92, and -925, (part # 200032). This differed from the 1½" midrange used in the AR-9 and AR-90. Tom Tyson has noted the difference in a previous discussion, regarding the AR-91:

Others have commented on the AR-91 (and this applies to the AR-92 as well), but there are some engineering highlights that have not been mentioned.

When the AR-9 was introduced, AR paid careful attention to the “boundary effect” (originally identified and characterized by Roy Allison), whereby the woofers were mounted on each side, close to the floor-wall intersection when the speaker was placed, as intended, back-against-the-wall. Unfortunately, AR did not give credit to Roy Allison for this development.

The AR-91 (and AR-92) also attacked the problem of boundary interference, and each enclosure placed the woofer close to the floor with the speaker systems also intended for against-the-wall placement. The compromise was that the AR-91 woofer was front-mounted, but the boundary-interference effect was somewhat reduced. The AR-91’s crossover also was modified to further minimize the effect. The AR-91’s cabinet volume was somewhat larger than the AR-3a’s, and system resonance was dropped to 40Hz (-3dB was 35Hz) with the “Q” set to 0.56. The result was a slightly overdamped system offset somewhat by the crossover and by the fact that the woofer was placed relatively close to the floor.

The AR-91 was also a “vertical” speaker, and by vertically stacking the woofer, midrange and tweeter, the interference effects were shifted into a vertical plane, rather than horizontal, and thus the frequency response from both speakers, as heard in the listening position, was more stable. The AR-91 tweeter was identical to that used in the AR-9 and AR-90, but the midrange unit was modified. This unit has a different part number as well. The 1-1/2-inch midrange unit used in the AR-9 and 90 used Ferro Fluid on *both* sides of the voice coil, and sealed off the cavity under the dome, thus raising the resonance frequency of the dome; but in the AR-9 and 90, the crossover was set quite high and this was not an issue. In the AR-91 the crossover was 700Hz, so the voice coil in the midrange used Ferro Fluid on the *inside* of the voice coil only, and thus the cavity beneath the dome was larger, lowering the resonance frequency of the dome. It could then operate within the 700Hz crossover range more effectively. The small “semi-horn” appendage on the front did not affect the lower cutoff frequency of the dome, as it was designed to help maintain efficiency in the upper level of the operating range. It did nothing below 3kHz according to Tim Holl.

The result of all this was an improvement in many ways over earlier 3-way AR speakers, and a speaker not always recognized for its fine performance. As Steve F remarked, it was somehow overlooked in the audio press.

--Tom Tyson

Robert_S

[mluong303]

Hi Steve

Before AR Limited 3 speaker system, there was AR Limited speaker system and that maybe the one you saw and listening to with Scan-Speak tweeter and priced for $4000 a set. I don't think this speaker system ever hit the street but skipped right into the AR Limited 3 speaker system right after...

The AR Limited 3 speaker system I owned was the later version and priced for $7000 a set with two Dynaudio D-76 3" dome midranges with special ordered rectangle face plate D-260 Dynaudio 1" soft dome tweeter in SRA layout. The 12" AR woofer was special designed cast aluminum frame with laminated cone(woven fabric over polypropylene) with soft rubber surround. It was the most impressive AR speakers I ever owned in term of quality parts used and built quality and attention to details all around.

The AR Limited 3 speaker system sound very transparency and spacious. The bass is very tight but different from the AR-9 and the classic AR-3a bass. The space age look of the AR Limited 3 speaker system will definitely set it apart from all other AR speakers I have ever seen... I think the people involved in the AR Limited series project was David Day Sequerra, Art Blumenthal, Dan D'Agostino and Mark Levinson.

Minh Luong

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[mluong303]

Hi Robert_S

If AR-915 share the same crossover as the AR-58s then would that mean the AR-915 midrange has the same spec as the AR-58s midrange then?

Minh Luong

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[Steve F]

Hi Steve

Before AR Limited 3 speaker system, there was AR Limited speaker system and that maybe the one you saw and listening to with Scan-Speak tweeter and priced for $4000 a set. I don't think this speaker system ever hit the street but skipped right into the AR Limited 3 speaker system right after...

The AR Limited 3 speaker system I owned was the later version and priced for $7000 a set with two Dynaudio D-76 3" dome midranges with special ordered rectangle face plate D-260 Dynaudio 1" soft dome tweeter in SRA layout. The 12" AR woofer was special designed cast aluminum frame with laminated cone(woven fabric over polypropylene) with soft rubber surround. It was the most impressive AR speakers I ever owned in term of quality parts used and built quality and attention to details all around.

The AR Limited 3 speaker system sound very transparency and spacious. The bass is very tight but different from the AR-9 and the classic AR-3a bass. The space age look of the AR Limited 3 speaker system will definitely set it apart from all other AR speakers I have ever seen... I think the people involved in the AR Limited series project was David Day Sequerra, Art Blumenthal, Dan D'Agostino and Mark Levinson.

Minh Luong

Yes, it was a Dynaudio tweeter, not a Scan-Speak. Davie Cahill said it was David Day who insisted on the "name-brand" tweeter. John Buzzota was the system engineer on the Limited 3 speaker, because I was at the factory when he gave the presentation and said he was the system engineer. I have no idea what Blumenthal, D'Agostino or Levinson had to do with anything. Buzzota also told us that if the Limited Series was a big success, then AR would have started building its own 12" woofer again in Canton MA. Alas, the Limiteds (and the Classic 30, 26, 22, and 18) all flopped quite badly, and AR ran away to CA with its tail between its legs, ending its glorious New England history on a rather pathetic note.

When you say the Limited 3's bass was "tight but different," what do you mean? Could the Limited 3 project powerful deep bass like a 3a or 9, or would you characterize its bass as being more "audiophile"--detailed and clean, but not particularly deep and muscular?

I agree that the Limited 3 had superb build quality, and its $7000/pr. price does not seem out of line for the high-quality materials it used and the fine appearance it presented.


Steve F.

[Robert_S]

Hi Robert_S

If AR-915 share the same crossover as the AR-58s then would that mean the AR-915 midrange has the same spec as the AR-58s midrange then?

Minh Luong

Sorry Minh, I'm unsure if the different part number signifies anything other than a cosmetic difference, the specifications of the 200044 midrange are unknown to me.

Based on the evidence of a shared crossover design (with identical tweeters and woofers being used), I'd certainly hazard a guess that the 200044 and 200032 are closer to each other in spec, than they are to the 200028, regarding interchangeability.

Incidentally, I've noticed that when shining a bright point-source light onto the front of the 200032 driver, some units I've looked at reflect back a clear/silver sheen, while others have a distinct orange shade. (The light must, of course, be of sufficient intensity to pass through the fabric.) The reason for this variation remains a mystery to me!

Robert_S

 

[soundminded]

Although I basically agree with Tom here, I’d like to look at things from a slightly different perspective.

It’s easy to fall into the trap of thinking all loudspeaker/acoustic knowledge/experience has existed all along, and to the same degree. So it’s very natural to simply pose the question “Couldn’t AR just tell from their measurements?” and equally natural to simply answer, “AR understood this phenomenon but had a different design philosophy at that time….”

I would offer for consideration the distinct possibility that AR did not fully appreciate the significance of driver interference and cabinet diffraction in the early-to-mid ‘60’s. (That was when the 2ax-3a-5 were designed. They may have appeared on the market in the late 60’s, but they were designed in the mid ‘60’s.)

I would say that the 3a’s drivers were mounted as they were—diagonally staggered—as much for mechanical/fitting convenience as any other reason. That the interference/radiation pattern was nearly the same horizontally as vertically was a coincidence, not a design goal. If it were a design goal, then the 2ax would have been that way also. It wasn’t.

AR continued to demonstrate that they didn’t consider it to be of significance right through the 10 Pi-11-12 ADD models. Those had their mids and tweets mounted all “wrong”—side by side, a la the 2ax—even though their cabinets were cosmetically intended, unambiguously, to be vertical, with that walnut trim strip at the bottom of the 11-12 (the door at the top of the 10 Pi) going side-to-side.

I submit that the 9 and the Vertical Series was not as much a simple “change of heart” by AR as it was a new awareness of that vertical mounting/interference design aspect—an awareness that simply didn’t exist to anywhere near that degree (if at all) in the mid-‘60’s. With the Verticals, AR finally realized that, yes, you could have wide dispersion, excellent far-field power response AND clear, almost interference-free near-field response, all at the same time.

That knowledge didn’t exist in 1965 the way it did in 1977. The collective understanding in any field advances with time, and as observers after the fact, we all tend to compress that in retrospect.

Steve F.

"I submit that the 9 and the Vertical Series was not as much a simple “change of heart” by AR as it was a new awareness of that vertical mounting/interference design aspect—an awareness that simply didn’t exist to anywhere near that degree (if at all) in the mid-‘60’s."

AR9 made advances in several important areas. The tower design allowed the tweeter and midrange drivers to be located optimally at ear level when the listener is in a seated position while keeping the woofers at the room boundaries where they get the most acoustic reinforcement from the room at the same time. The 8" driver turning it into a four way design was located ideally allowing excellent coupling to both the woofers and UMR. Three way designs cannot achieve all of these goals simultaneously. Personally I think incorporating the vertical alignment and acoustic blanket was merely acceding to the market whims/fads of the moment and was not of particular importance in terms of actual usable performance. Modifying the cabinet of the 3 way "bookshelf" design only slightly could have aligned the midrange and tweeter vertically, brought them forward, and allowed installation of the acoustic blanket without tripling the price of the speaker system the way AR9 did. The larger cabinet and second woofer was in large measure the cause of the higher cost. The result was a speaker with substantially more low frequency capability than AR had ever built into a single loudspeaker system. The four way design was a major rethinking of the problem of building a multiway system and an acknowledgement of the limitations of a three way design given the reality that most loudspeaker drivers only have a usable range of 2 1/2 to 3 octaves. I consider AR9 to be AR's last evolutionary step in a process of creating a high fidelty loudspeaker system for the home based on acoustic suspension woofers and dome midranges and tweeters. It continues to exhibit qualities I have not heard duplicated by any other speaker, either AR's or anyone elses.

[Carlspeak]

"I submit that the 9 and the Vertical Series was not as much a simple “change of heart” by AR as it was a new awareness of that vertical mounting/interference design aspect—an awareness that simply didn’t exist to anywhere near that degree (if at all) in the mid-‘60’s."

AR9 made advances in several important areas. The tower design allowed the tweeter and midrange drivers to be located optimally at ear level when the listener is in a seated position while keeping the woofers at the room boundaries where they get the most acoustic reinforcement from the room at the same time. The 8" driver turning it into a four way design was located ideally allowing excellent coupling to both the woofers and UMR. Three way designs cannot achieve all of these goals simultaneously. Personally I think incorporating the vertical alignment and acoustic blanket was merely acceding to the market whims/fads of the moment and was not of particular importance in terms of actual usable performance. Modifying the cabinet of the 3 way "bookshelf" design only slightly could have aligned the midrange and tweeter vertically, brought them forward, and allowed installation of the acoustic blanket without tripling the price of the speaker system the way AR9 did. The larger cabinet and second woofer was in large measure the cause of the higher cost. The result was a speaker with substantially more low frequency capability than AR had ever built into a single loudspeaker system. The four way design was a major rethinking of the problem of building a multiway system and an acknowledgement of the limitations of a three way design given the reality that most loudspeaker drivers only have a usable range of 2 1/2 to 3 octaves. I consider AR9 to be AR's last evolutionary step in a process of creating a high fidelty loudspeaker system for the home based on acoustic suspension woofers and dome midranges and tweeters. It continues to exhibit qualities I have not heard duplicated by any other speaker, either AR's or anyone elses.

Soundminded, how would you rate the TSW-910 against the 9? It was a later version of the 9 perhaps with similar driver compliment and also a 4-way, albeit with drivers of lesser quality?

[Carlspeak]

Sorry - posted twice due to sluggish response.

[soundminded]

Soundminded, how would you rate the TSW-910 against the 9? It was a later version of the 9 perhaps with similar driver compliment and also a 4-way, albeit with drivers of lesser quality?

Sorry Carl, I can't comment about TSW-910. I never heard it. However, keep in mind that I not only "re-engineered" my AR9s, I never claimed they are the best that can be done. They have their shorcomings but not in the conventional sense, at least not my pair. One day I'd like to engineer speakers that incorporate all of the best features of different designs I'm aware of that others created or developed myself. I'm sure it would be a difficult and expensive undertaking.

[mluong303]

Help Tom!

By any chance you have the mid range specification on hands for the 200028 and 200032? Thanks.

Minh Luong

[mluong303]

Hi Steve

It wasn't an bad idea that David Day insisted on using the Dynaudio tweeter and midranges for the AR Limited 3 speaker system. Beside from its reputation, Dynaudio drivers were the most expensive and quality built drivers at the time compared to all other brands. Also the Dynaudio D-260 tweeter can handle very high powers and the 3" D-76 midrange could go down to 300Hz crossover point of the AR Ltd 3 which no other midrange dome drivers from other manufacturers could reach. In order to accomplish the Symmetrical Radiation Array(SRA) precisely AR had ordered Dynaudio to fabricate the rectangular face plate for the D-260 so both D-76 could be placed closer to the D-260 tweeter rather then staggering two D-76 on top of the regular round face plate D-260. It has certainly shown that AR doesn't just order off the shelves expensive drivers, slap everything together and put an AR logo on top of it. All crossover parts including the extra thick glass epoxy crossover boards were carefully selected and order from different manufacturers who were best known for what they make namely Rifa, Wima, Sprague, Solen, Ohmite, Esoteric, etc.

AR Limited 3, the 3 stands for three way design even-though it used one extra midrange driver for more output and higher power handling. The main design goal was to use a dome tweeter, two dome midranges with a 12" woofer to bring back the famous AR-3a speaker's fame to the Hi-End domain and personality I would say AR had accomplished that goal amazingly well with the AR Limited 3 speaker system. However AR had chose the wrong Dealer to market the AR Limited system whom was Sound by Singer in Manhattan. A very successful Hi-End dealer who already had too many name-brands to sell in their store and why would they recommend to their clients to purchase the AR Limited system and make less commission that way! AR should have just rented a couple of news-stand spots in Grand Central terminal to form the AR music room just like 40 years ago to display the AR Limited system along with the AR-303 series speakers to hundred of thousands people traffic through the area every day to find out what AR stands for and what AR can made their musics sound like...

The AR Limited 3 bass is very tight and muscular but need very high power amp to made it move nicely. The 12" cast frame woofer with rubber surround and stiff spider look very similar to the NHT 1259 woofer. My 225w/ch@8 Ohms and 350w/ch@4 Ohms NAD power amplifier couldn't drive the AR Limited 3 speakers to its full potential but if I had money left at that time to purchase a 400w/ch Krell Amp, I am sure I wouldn't have sold them to search for other alternatives!

Dynaudio factory in Denmark


Minh Luong

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[Steve F]

Soundminded, how would you rate the TSW-910 against the 9? It was a later version of the 9 perhaps with similar driver compliment and also a 4-way, albeit with drivers of lesser quality?

I would rate the 910 as a very good "B+/A-" speaker. Very good indeed. I've heard them many times.

Not in the same class as the 9.

The 9 had a coherence and evenness of response and consistent radiation vs. frequency that the 910 was not even designed to have. As I have opined before on these pages, the 9 was a sort of "Manhatten Project" speaker, one that galvanized AR's entire engineering resources into one focused effort--an effort to solve so many preveiously-unsolved speaker issues, and to do them all simultaneously. It succeeded to an amazing degree, such that a properly-operating set of 9's is still a superb speaker even today, and in some ways, its combination of attributes has never been equaled.

Before all the modern-speaker proponents jump all over that last statement, note that I'm not claiming that this or that one or two particular aspects of the 9 haven't been bettered in the last 30 years. Of course some aspects of the 9 have been eclipsed.

But the total combination of strengths and issues solved by the 9 has never been equaled.

The 910, in contrast, was essentially a formulaic, marketing-driven placeholder. Not that there's anything necessarily wrong with that, but you can just hear Marketing saying, "....and with this new TSW line, we need a big floorstander with two 12's, something with a model number that begins with 9.....and throw in that Blanket thing, too...."

The 910 was not a bad speaker. On the contrary, it sounded very, very good. But it didn't represent any new thinking on AR's part, and if you read Julian Hirsch's review in the June 1987 Stereo Review, its FR is somewhat erratic, its dispersion was uneven, and its bass is not as flat-out incredible as the 9's. If you know how to read between the lines in Julian's reviews, he clearly was "d*mning the speaker with faint praise," as the saying goes. The best thing he could muster was something along the lines of, "Few would tire of its smooth, easy sound." That's the best he could say?

Like all the TSW's, the 910 was a very good, solid speaker, but not breathtakingly great like the 9.

Steve F.