Steve F

I have known Andy Kotsatos quite well, both professionally and personally, for many years. I have the utmost respect and admiration for his accomplishments and contributions to our industry. What follows are excerpts from two earlier posts of mine (around 2002 or 2003) that may shed some interesting light on his involvement in voicing/designing the Advents and the Advent design philosophy. This comes from my direct association with him, and the many conversations we had about the "old days." (Note: Both Andy and Moses Gabbay have retired from Boston Acoustics since my original posts.) First post: Andy's dad worked in the kitchen of a famous NY hotel as a busboy and helper. He was "vertically challenged,” and the kitchen staff, mostly French-speaking, called him Le Petite. That name stuck until 1994, when Andy had had enough and went back to his Greek roots, re-assuming his original family name of Kotsatos. Andy worked retail at a Harvard-square (Cambridge MA) hi-fi store in the early 60's that featured KLH. He then went to work at KLH as a product manager, where he met Henry Kloss. He went with Henry to Advent in the late 60's and helped Henry voice the original Advent and Smaller Advent. Andy was totally responsible for the design of the New Advent loudspeaker, which was a very nice product. When Advent ran into financial trouble in the mid to late 70's (remember, Henry founded Advent as a vehicle to develop and market big-screen TVs; the speaker end of Advent was just supposed to supply the cash flow), it changed ownership, and things went downhill very fast. Andy and Advent's credit manager, Frank Reed, saw the handwriting on the wall, and they left Advent to start Boston Acoustics in 1979. Their timing was perfect. Frank was a business genius who carefully guided a bunch of engineer/hobbyist store owners in the proper ways to merchandise and run their businesses profitably; Andy was the product designer, and came up with several great products in the classic Advent tradition. Very shortly after the company's founding, Moses Gabbay, a top AR engineer, joined BA. Today Andy is Chairman of the Board and Moses is CEO. Frank passed away in November 1996, but was actively involved right up until his death. Andy never worked at AR. He has always considered them to be the "enemy," like a Red Sox-Yankees or Ali-Frazier rivalry. If you run into him at a CES show, a BAS meeting, or some other industry gathering, his passions and memories of the heated days of the 60's-70's speaker business are easily--and fascinatingly-- elicited. Next post (partial)— The fundamental reasons for the difference in the sound of Advents and AR’s in the late 60’s-early 70’s era had to do with the very different design philosophies between the two companies. KLH/Advent/Kloss, as Tom pointed out, relied mostly on subjective measurements and the evaluation of the speaker’s octave-to-octave balance. Henry believed that people responded to sound in broad frequency blocks—octaves—and if the relative balance from one octave to the next were correct, the device, whether it was a speaker, a compact stereo system, a radio, or whatever, would be pleasing and satisfying to the end user. For the original Large Advent, Henry did the design work on the drivers and enclosure in 1968-1969, but gave an early pre-production prototype to his associate and protégé, Andy Petite (who later changed his name back to his original Greek family name, Andy Kotsatos after he founded Boston Acoustics), along with a 10-band graphic equalizer. “Here, take this home, and make it sound the way you like it. Mark down the settings of the EQ when you’ve got it right, and then we’ll talk.” So he did, and then he and Henry compared notes. That’s how the Large Advent was voiced—by Andy getting its octave-to-octave balance to be satisfying and convincing on as wide a range of program material as possible. It was hugely successful, obviously, because the speaker sold extremely well—although there were pure marketing decisions that contributed to the speaker’s success as well, which we’ll explore later. Henry and Andy also believed in the importance of smooth on-axis response as a starting point for good loudspeakers. They didn’t place much importance on power response at all. Villchur and Roy Allison believed much more in the power response approach. Very simply stated, power response is the total energy radiated by a speaker, measured in the reverberant field. It is essentially a summation of all the on-and off-axis “frequency responses” of the speaker, including the room reflections. In an energy response measurement, the on-axis response of the speaker is the strongest component of the measurement (because it is the axis on which the speaker puts out its greatest energy), but it is only a part of the total measurement... Steve F.

Vern, I've never seen an AR-1x with the 3 1/2" tweeter. That doesn't mean that the 1x never used that tweeter; it just means I've never seen one. If you have an ad or an old piece of lit showing the 3 1/2" tweeter in the 1x, I'd love to see it, to expand my historical knowledge of the Classic series. BTW, as a point of interest: when I inherited my 3a's from my older cousin (he retired in 2001, and wanted to down-size his audio equipment), I took them to AB Tech to be refurbed. They replaced the woofers with Tonegens and upon taking the old ones out, they found that one was a ceramic/foam surround, the other was an Alnico/cloth surround. My cousin bought them new from a local MA retailer in 1972. All that time, he never knew that he had one of each flavor. Steve F.

>Yes, the AR-2AX has the flat front wire meshed cone driver >with fiberglass as it's midrange driver. This third party >driver was also used as the earlier AR-4, AR-1X, AR-2X >mid/tweeter driver. Vern, Hate to be a nit-picker, but in the interest of historical accuracy, the tweeter in the 1x was the 2 1/2" tweeter (similar to the 4x), not the 3 1/2" unit from the 4, old 2x and 2ax. Steve F.

The "new" AR-2x used the exact same 2 1/2" tweeter as the AR-4x. The AR-1x used a 2 1/2" cone tweeter also, but that was a 4-ohm system. the 2x and 4x were 8-ohm systems. No AR-4 series speaker ever used a dome tweeter. The AR-4 used a 3 1/2" cone (as did the early AR-2x's), crossing over at 2,000Hz. This 3 1/2" cone was also the midrange driver in the 2ax, both "old" and "new." The AR-4x used the 2 1/2" cone, crossing over at 1200Hz. The AR-4xa used a 1 1/2" cone (like the AR-6 and -7) crossing over at, I think, 1600Hz. My literature is in the basement, and I'm on the second floor, too lazy to walk down and up the two flights to confirm this. But 1600Hz sounds right. Steve F.

The T930 II was a slight revision of the original T930. The 930 was introduced around 1987-88. It was a 10" 3-way acoustic suspension speaker , with a 6 1/2" midrange and a 1" soft-dome tweeter. BA's design/engineering was extremely competent at that time, and the 930 was a very good, straightforward design. It had a gutsy, ever-so-slightly forward sound quality, solid bass into the mid-40's, and a relatively benign impedance that ensured good compatibility with mass-market receivers. The Series II was identical to the original, except that the Series II inverted the tweeter and midrange (mid on top, tweeter below in the II), to improve its lobing characteristics. The Series II was intro'd around 1990, and stayed in the line until the VR20-30-40 floorstanding speakers replace the T Series (T830, T930 II, T1030) in 1994. List price for the 930 and 930 II was $750/pr. Steve F.

This is a slightly more complex area than we might think at first glance. The technical answer to your question is yes, the two speakers will have similar anechoic FR response, especially from the mid-bass on up. In-room FR response will be somewhat different, since the 98’s cabinet is much shorter than the 9’s and therefore the speaker’s response will be affected differently by its dimensional relationships to both the room boundaries and the listener’s ears. The low bass will also affect the perceived tonal differences between the two speakers. The AR-5 and 3a were the “same” speaker except for the low bass, yet in practice the two had markedly different personalities—more than the “numbers” alone would have predicted. Now, the difference between the 3a-LST-type 12” bass response and the 2ax-5 10” response was greater than the difference between the 10-inchers and, say, the 6-4x-7-type 8” response. A great deal has been written in the audiophile press over the years about the masking effects of low bass (below 40 Hz) on midrange transparency, and whether, or to what extent, the presence of truly deep bass might affect the perceived tonal balance and transparency of any given speaker system. I believe the 98 had pretty much the same rated low-end response as the 3a-LST-11 series of speakers: down about 3dB at 35Hz or so. I don’t remember if AR ever rated the 9 LS’s LF response, or did they? Down 3dB at 28Hz? I don’t recall off the top of my head. There’s a lot of usable musical information in the range between the 5’s LF response (-3dB at 45Hz) and the 3a’s –3dB at 35Hz. Low C organ pedals (like the famous “2001” opening sequence) occur at 32Hz—well within the 3a-11-98 range, but clearly too low for the 5-2ax-48 speakers. Is there as much real, usable, musical information available on commercial recordings that would show up the difference between the 9 LS and 98 LS? I don’t know. I will freely admit that I have never A-B’d the 98 LS and 9 LS side-by-side. My hunch—-and it’s only a hunch—-is that the 98 and 9 are somewhat closer to each other than the 5 was to the 3a. Steve F.

Aleksandar, I have never seen a review of the 98, at least not by any of the "Big Three" (Stereo Review, High Fidelity, Audio). High Fidelity did review the 9LS and gave it an outstanding review, claiming it had "perhaps the deepest, firmest, most natural" bass they'd ever heard. Some time later, they reviewed the 78LS and it came off merely as a good product in a sea of good products. Certainly nothing to harken back to the glory days of previous AR 12" 3-ways like the 3, 3a, or even the 10Pi/11. There is a scanner at my work, although they look askance at people using it for personal reasons. I'll try to scan these two reviews for you and send them your way in the near future. BTW, I followed your 98 restoration project when you originally posted it, and it is quite impressive. Steve F.

The original AR-8 from 1973-4 was a 10" 2-way. It was not a particularly successful product. The AR-8 B, Bx, Bxi, etc. series from the early-mid '80's was a 6.5" 2-way. They were completely different speakers. Usually, a manufacturer will wait much longer than 10 years before reprising an earier model number or name. As an example, the Chrysler corporation is introducing a new SUV next year called the Aspen, fully 30 years after the ill-fated 1976 compact car of the same name. Chances are good that the 2006 Aspen's target market will have little or no recollection of the quality- and rust-plagued car that symbolized Chrysler's near-fatal problems 30 years ago. But no one will ever accuse the 1970's-80's AR of marketing genius. Steve F.

Victor was well-known for his tenure at KLH, but he joined AR in 1975 as head of engineering and championed the intro of the ADD series (initially the 10Pi, 11, and MST/1.) I remember listening to him when he was a guest on Shop Talk (a 70's-era Boston hi-fi radio talk show) in the spring of 1976, extoling the virtues of the MST ("The MST can pump out bass like no 8-incher has any business doing!"). Victor was primarily responsible for the engineering efforts that went into the 1976-7 live-vs-recorded demonstrations with drummer Neil Grover and the 10Pi. That was quite a remarkable demonstration, as it demanded so much more in terms of power handling and HF energy response than AR's previous L v.R presentations. With very minor changes, the 10Pi's used for this demonstration were stock items, and none of the changes involved any of the drivers. Victor told me that AR's primary objective in doing the Grover/10Pi demo was to prove that a relatively "conventional" 12-inch 3-way speaker could indeed recreate the effect of live music if it were properly designed, had verifiable, accurate response, and used rugged drivers of extremely high reliability. The 10Pi (and 11) had all the attributes needed. Victor also told me that the 11 would have done just as well as the 10Pi (they used the 10Pi in the '2 pi' position anyway, the same as the 11 was), but they wanted the top-of-the-line model to get the "glory" of the success. (BTW, the drummer was Neil Grover, NOT "Buddy Rich" as someone said on the Forum recently.) Steve F.

AR was "this close" to marketing the 3a Improved in the US in the spring of 1974, but had a change of heart at the last minute. With the 10Pi and 11 less than a year away, there would have been no valid reason to try to re-introduce a 3a variant at that time. The same holds true for the 2xa, although as far as I know, that model was never even contemplated for the US market. Steve F.

There are really two separate discussions taking place. Let’s identify them and address them independently: Discussion No.1—How to describe a 3a/LST/9 woofer for replacement of the surround: The point was made that if someone were to ask for a generic 12" surround kit, they might be supplied with a JBL 12" surround that wouldn’t fit the AR 12" woofer because the JBL is too big. This seems at first glance to be a valid consideration, but if it’s thought through, the logic is specious. What the parts suppliers should do is identify what woofers their various surround kits are meant to used with. If supplier ABC has a surround kit for the 3a/LST/9, they should identify it as "Surround kit for AR 12-inch woofer." Calling it an "11-inch" woofer still confuses things in the customer’s mind, since no such woofer has ever existed. Take the plight of Mr. Casual Customer. Mr. Customer has owned ARs for a long time. Now they sound a little "funny." He takes off the grilles, notices that the surrounds have rotted out and calls his friend, Mr. Stereo Expert. Mr. Expert says, "Hey Casual, it’s no big deal. What you should do is call Supplier ABC and ask for a re-surround kit. Just tell them what speakers you have, and they’ll send them out. You’re a handy guy; you won’t have any trouble doing the work yourself." So Mr. Casual calls ABC and says, "I’ve got these AR-3a speakers. The owner’s manual says the woofer is 12 inches, so I guess I need a 12-inch AR surround kit." ABC says, "Well, for your speaker, we have an 11-inch kit, not a 12-inch kit." "Huh? My manual says 12 inches. I’m confused. Why do you want to sell me an 11-inch kit if my manual says 12 inches?" See the problem? Misidentifying it as "11-inches" helps nothing and potentially causes confusion. As to the "JBL’s 12 inches is larger than AR’s 12 inches" argument, this is particularly vacuous. Every manufacturer’s parts are specific to that manufacturer. When you go into an auto parts store to buy an air filter for a Chevy 3.8-liter 6-cylinder engine, you don’t ask for a generic "6-cylinder air filter." You ask specifically for a Chevy 3.8-liter 6-cylinder air filter. The air filter for Ford’s 3.0-liter engine is still a Ford "6"-cylinder air filter, even though it’s smaller than the Chevy filter. We don’t all of a sudden refer to the Ford as a 5-cylinder engine. The various suppliers should identify their surround kits by the woofers and brands with which they’re meant to be used. If they identified their surround kits as "AR 12-inch surround kit, for use with AR models 3a, LST, 11, 10Pi, 9, 91, 910, etc," there would never be any problem or confusion. They shouldn’t re-write history or try to be too clever. This isn't arrogance on our part. There is simply no upside benefit to Layne and others referring to the 3a woofer as 11 inches. No upside at all. But, a very definite potential downside. So why do it? Discussion No. 2—What we call these woofers on this Forum We should call them 12-inch woofers amongst ourselves, because we know better--right? Now if you’ll excuse me, we’re having a houseful of people later on today for our annual Christmas Eve dinner, and if I don’t get down there to help my wife pretty soon, she’ll strangle me with those 11" surrounds. Happy Holidays, everyone. Steve F.

Now that Tom has accurately recounted the developmental history of the AR 12" woofer in beautifully complete, correct detail, I'd like to add my opinion to this discussion with regard to the calling of this driver an "11-inch" driver. Long-time members of this forum know that this is a pet peeve of mine, and for those of you for whom this is a repeat, I apologize in advance. Herewith, then, is a re-run of two of my postings from almost two years ago: ">>#1751, "RE: Real McCoy ! New AR eyeball mid" In response to Reply #0 >>11" Woofer part #1210003-2 Aren't we tired of outsiders calling the AR 12-inch woofer an "11-inch" woofer? People should know better, for two reasons: 1. Industry-standard practice is to measure the frame diameter of a woofer, NOT the piston diameter or the surround diameter. Measured this way, the 3a's woofer is 12 inches. Any woofer--AR's, KLH's, Advent's, anyone's-- would be less than the formal measurement if you went strictly by piston diameter. No one is trying to "get away" with anything or fool anyone. It's just the standard way that drivers are identified. This leads to reason no. 2 2. AR had 10-inch woofers and 12-inch woofers. If some parts supplier insists on foolishly and inaccurately referring to an AR 12-inch woofer as an "11-inch" woofer, then there is the all-too-real possibility of a less experienced hobbyist ordering the wrong driver for their speaker. AR called it a 12-inch woofer. For the sake of industry-standard practice, ordering accuracy, and historical consistency, the woofer should be called what it is: a 12-inch woofer. Period. People need to stop this nonsense. Steve F. #1756, "RE: Real McCoy ! New AR eyeball mid" In response to Reply #5 The AR 12" woofer measures 12" across the wide part of the frame, 11.5" across the truncated section of the frame, 9.5" from mid-surround to mid-surround, and 8.5" from the inside of the surround (the actual "cone" diameter). Smaller drivers are correspondingly smaller. As I said, driver diameters are wider than the actual cone measurement, but this is just the way the industry measures drivers. The issues with Layne and others calling the 3a/LST woofer an 11" woofer are these: 1) First and foremost, it serves no useful purpose. Calling the driver an 11" driver does not impart any new, helpful information to the end user. How do you benefit by Layne--or anyone else-- intentionally mis-identifying the woofer as an 11" woofer? The answer is, of course, you don't benefit at all. It's just bad information on their part, potentially misleading, and historically inaccurate. 2) It seems as if Layne and others want to demonstrate how clever and discerning they are by their "discovery" of the actual size of this well-known, historically-significant woofer. It's almost as if their thought process is, "Well, all you hobbyists out there THINK it's a 12" woofer, but we're the real experts, and we've discovered that it's only an 11" woofer." It's so childish. Calling it an 11" woofer benefits no one, confuses the issue, incorrectly re-writes history, ignores industry standard measurement practices--all for the sake of what? Convincing themselves that they've "discovered" something? Padding their own ego? I have zero tolerance for non-productive, wasted communication that imparts inaccurate data." OK, I've said my piece. It's a 12" woofer. On this site, we know better. Case closed. Steve F.

Interesting--I bought my AR-2ax's from Fred Locke in Avon CT in 1971. They really didn't want to sell them to me, since they were pushing Infinity 1001's very hard at the time. I got almost as much pleasure from buying AR speakers from a dealer who was trying to steer me away from AR as I did from the speakers themselves! Steve F.

"In mid-to-late 1970s, Advent brought out an improved version of The Advent Loudspeaker called "The New Advent Loudspeaker," and I think it was designed (or the improvements were engineered) by Andy Kotsados (currently CEO of Boston Acoustics). It, too, was a superb speaker for the price, and was available in walnut veneer or in a vinyl-clad utility cabinet." Andy did design it. Andy's last name is, of course, Kotsatos, not Kotsados--probably just a typo!! My recollection of the New Advent was that although it had a smoother and somewhat more refined sound than the original, it did not have the same mid-40's Hz system resonance as the original Advent. Thus, the "Advent value advantage" over AR--having 3a-class bass extension at far lower cost--was gone. I think the AR-14 and -12 were superior speakers to the New Advent in terms of smoothness and musical accuracy. The AR ADD 10" models had slightly larger internal cabinet volumes compared to the previous-generation AR 10" speakers (the 2 series and the 5), so their deep bass extension was very marginally improved as well. The 12 especially, with its ferro-fluid cooled 2 1/4" cone midrange, is an excellent speaker and a terrific value.