The AR Amplifier at the McIntosh Amplifier Clinic

[tysontom]

A test done at a 1968 McIntosh Amplifier Clinic, performed by Dave O'Brien, demonstrated the excellence of the AR Amplifier. Dave would only do the 20-20kHZ distortion curve at the rated 50-watt level, but I asked him to check the maximum steady-state power (at under 1% harmonic distortion) output at 4 ohms and 8 ohms, and he did test for that as well. He knew the amp was a good performer, and said so. Notice that the harmonic distortion falls under the minimum-standard McIntosh performance level at the AR amp's rated power, from 20-20kHz, both channels driven (a requirement of McIntosh).

--Tom Tyson

[Steve F]

The Mac amp clinics were enjoyable events. Mac produced some really good equipment and they did much to broaden the awareness of amplifier performance with these clinics. Most Mac dealers did not retail AR products (at least by the early 70's, because of the well-documented AR marketing policies of that era), so when an AR amp showed up and did well, it was not well-recieved by the store hosting the clinic.

Same for Dynaco products--they were mostly mail-order discount items by 1971 and retailers hated them, as they hated AR, because of the limited profit potential those brands offered.

My friend and I had each built SCA-80 integrated amps and we took them to Sound Ideas in W. Htfd CT for the Mac clinic. My friend's amp had THD at 40 watts RMS that rose in the extremes to about 1.3%, causing the Mac guy to derisively scoff, "Yeah, they're all like that, even though they claim .5%"

Mine, on the other hand, was .2% mid-band, and .3% at the extremes. (Pure happenstance, mind you: I'm not claiming that some exquisite assembly technique on my part had anything to do with it! Far from it--it was my first experience with a soldering iron. I was 17.). The Mac guy said he'd never seen a Dyna that good: "You must've had all 'plus' parts."

I came away with valuable insight into why these clinics existed: they were done to sell Mac amps and bring publicity and foot traffic into the host store.

Steve F.

[dynaco_dan]

The Mac amp clinics were enjoyable events. Mac produced some really good equipment and they did much to broaden the awareness of amplifier performance with these clinics. Most Mac dealers did not retail AR products (at least by the early 70's, because of the well-documented AR marketing policies of that era), so when an AR amp showed up and did well, it was not well-recieved by the store hosting the clinic.

Same for Dynaco products--they were mostly mail-order discount items by 1971 and retailers hated them, as they hated AR, because of the limited profit potential those brands offered.

My friend and I had each built SCA-80 integrated amps and we took them to Sound Ideas in W. Htfd CT for the Mac clinic. My friend's amp had THD at 40 watts RMS that rose in the extremes to about 1.3%, causing the Mac guy to derisively scoff, "Yeah, they're all like that, even though they claim .5%"

Mine, on the other hand, was .2% mid-band, and .3% at the extremes. (Pure happenstance, mind you: I'm not claiming that some exquisite assembly technique on my part had anything to do with it! Far from it--it was my first experience with a soldering iron. I was 17.). The Mac guy said he'd never seen a Dyna that good: "You must've had all 'plus' parts."

I came away with valuable insight into why these clinics existed: they were done to sell Mac amps and bring publicity and foot traffic into the host store.

Steve F.

Hi there;

I was never at a Mac clinic but there was two rumours flying around here in Vancouver at that time period.

These were from non-AR supporting and non-Mac stores.

1. Some Mac speakers used the AR-3A drivers, was told to me at the Vancouver Hotel 1971 HI-FI show.

2. Mac clinics would not test the AR amp as they caught fire.

Isaac Hayes', "Shaft," was the record cut of choice by almost all displayers, LOUD.

The typical comment's from local non-supporting AR dealers was that the amp caught fire and the AR turntable used a common drugstore elastic band to drive the clock motor.

We all know how inaccurate rumours can be sometimes.

Vern

[Pappas3278]

Great post! Thanks for sharing.

-Mike

[dynaco_dan]

Great post! Thanks for sharing.

-Mike

Hi again;

Of course 1 and 2 above were when the AR-3A was not being bashed as an ugly example of a badly finished speaker's front baffle.

Or the Dynaco amp and pre-amp kits were opened up to point out how ugly they were wired compared to Quad products.

Mac's as I always read and heard, at least in the early years, were of the highest caliber of fit and finish, not necessarily the best sonically though.

I say that as we all have our sound and personnal preferences, even if someone else does not agree or disagree with us.

They may have been considered the, "Rolls Royce", of hi fi equipment, in their day.

Which is better sounding, tubes or solid state?

There again, personnal choice.

Too bad I missed those Mac clinics, my loss.

Vern

[tysontom]

The Mac amp clinics were enjoyable events. Mac produced some really good equipment and they did much to broaden the awareness of amplifier performance with these clinics. Most Mac dealers did not retail AR products (at least by the early 70's, because of the well-documented AR marketing policies of that era), so when an AR amp showed up and did well, it was not well-recieved by the store hosting the clinic.

Same for Dynaco products--they were mostly mail-order discount items by 1971 and retailers hated them, as they hated AR, because of the limited profit potential those brands offered.

My friend and I had each built SCA-80 integrated amps and we took them to Sound Ideas in W. Htfd CT for the Mac clinic. My friend's amp had THD at 40 watts RMS that rose in the extremes to about 1.3%, causing the Mac guy to derisively scoff, "Yeah, they're all like that, even though they claim .5%"

Mine, on the other hand, was .2% mid-band, and .3% at the extremes. (Pure happenstance, mind you: I'm not claiming that some exquisite assembly technique on my part had anything to do with it! Far from it--it was my first experience with a soldering iron. I was 17.). The Mac guy said he'd never seen a Dyna that good: "You must've had all 'plus' parts."

I came away with valuable insight into why these clinics existed: they were done to sell Mac amps and bring publicity and foot traffic into the host store.

Steve F.

Great comments by Steve!

The McIntosh Clinics were done primarily for the McIntosh dealers for the benefit of McIntosh owners, but I believe that soon after the clinics were started (they ran from 1962 until 1991 and were managed primarily by Dave O'Brien of McIntosh, who traveled extensively conducting these clinics), they began to allow competitive brands of amplifier/preamplifiers to be tested; therefore, since it was found that many competitive amplifiers would not meet their published specifications, this became somewhat of a marketing coup for the Mac dealers. Early on, if a McIntosh amplifier failed to meet its "guaranteed" published specifications, O'Brien and his assistants would actually try to repair the amp on the spot as part of the promotion for Mac dealers. This service ended later on, but was a great promotion in the beginning. I don't believe that Dave O'Brien, a professional trained in electrical engineering, ever intentionally "bad-mouthed" competitive amplifiers, but the sponsoring dealers and their sales people freely and openly disparaged competitive products, including every non-Mac amp I ever took to one of their clinics. Therefore, in my experience at least, it was always the dealer and sales people, not McIntosh, that would publicly criticize another product at the clinics.

The key to McIntosh's success was to test an amplifier with both channels driven simultaneously to full-rated output, from 20-20,000 Hz, and measure the distortion at points along the way. Most amplilfiers are never required to perform this way in real life, so the spec was probably impractical, but McIntosh engineers designed their amplifiers to specifically meet power-output specs with both channels driven, from 20-20kHz at under 1/2 of 1% harmonic distortion. There were many fine, competitive amplifiers made during the formative years of high fidelity that would not only not meet their published specifications, but would only meet specs for a brief period before over-heating, shutting down or downright self-destructing. Mac amps, on the other hand, would usually run wide-open indefinitely, without failure or fanfare, and this durability/reliability quality was the primary reason that McIntosh amps were so expensive. Measurement instruments used were Hewlett-Packard 200CD audio oscillators, Hewlett-Packard model HP-331A and HP-334A harmonic-distortion analyzers, HP voltmeters, scopes and HP frequency counters, etc. Dave O'Brien used a "French Curve" template to draw out the curves, since the measurments were done manually.

Speaking of Dynaco, I took my first Dyna PAS-3X preamp and Mark III amp to the McIntosh Clinic in 1967, and both units were tested by O'Brien (see attached file) and performed relatively well. The next year, same time I took my AR amp for test, I took my two well-worn (and probalby out-of-bias) Mark IIIs in for another test. This time they did okay, but distortion was up quite a bit (see attached files).

--Tom Tyson

[genek]

but the sponsoring dealers and their sales people freely and openly disparaged competitive products, including every non-Mac amp I ever took to one of their clinics. Therefore, in my experience at least, it was always the dealer and sales people, not McIntosh, that would publicly criticize another product at the clinics.

The Mac clinics where I grew up were different. There was only one "good" hifi dealer within 3 or 4 towns of us, and they carried every brand under the sun, from plastic record changers to high end (in different listening rooms), so it was not unusual to see Macs on the listening room shelves sitting next to AR, Scott, and yes, I think I even saw Dynaco (but probably just the factory-assembled). They even discounted brands whose manufacturers chose not to invoke their "fair trade" powers (which is one reason why I ended up auditioning AR speakers in the first place), so those manufacturers who did not discount had two choices: sell at full price in their store or refuse and tell any interested party that they would have to drive 50 miles to the next nearest dealer (back in the 60's, 50 miles was considered a *long drive* by people living in the NE).

[tysontom]

The Mac clinics where I grew up were different. There was only one "good" hifi dealer within 3 or 4 towns of us, and they carried every brand under the sun, from plastic record changers to high end (in different listening rooms), so it was not unusual to see Macs on the listening room shelves sitting next to AR, Scott, and yes, I think I even saw Dynaco (but probably just the factory-assembled). They even discounted brands whose manufacturers chose not to invoke their "fair trade" powers (which is one reason why I ended up auditioning AR speakers in the first place), so those manufacturers who did not discount had two choices: sell at full price in their store or refuse and tell any interested party that they would have to drive 50 miles to the next nearest dealer (back in the 60's, 50 miles was considered a *long drive* by people living in the NE).

You describe how the dealers were different; i.e., the only good dealer was selling every brand, and I follow you on that. But you didn't describe how the Mac Clinic was different. How was it different? You make a good point on the "Fair-Trade" dealers and their practices.

The old "Fair-Trade Laws," which allowed for price-fixing on products, were partially repealed in the late 1960s (and completely in the 1970s), I believe, and this is one reason that McIntosh, JBL, Altec Lansing, ADS, KLH and many other manufacturers sought dealers that specialized in premium products set in an upscale, "salon" atmosphere. These specialized dealers were strongly "encouraged" to sell these products at list price, but there were no specific written mandates to do so (as that would be unlawful); but if a dealer was found to be discounting, the manufacturer could easily find any of several reasons to "pull" the franchise and discontinue selling to this dealer. These specialized dealers were not volume dealers, and they avoided selling products that were typically sold in large volumes at discount stores and catalogs. There was a veiled threat that a franchise could be revoked for discounting, but the manufacturers always denied this. Manufacturers distributed franchises sparingly in a particular geographic area, when possible. This way the manufacturer would see to it that no other dealer close by had the same franchise and thus "eliminating" competition to some degree.

AR's marketing philosophy was very different from this "salon" approach. AR's Ed Villchur believed in the "laissez-faire" approach to marketing, which meant to let the market seek its own level, and let the products sell on their own merit. It was the old, "build-a-better-mousetrap-and-they-will-beat-a-path-to-your-door" philosophy. This method of marketing obviously worked well for the innovative Acoustic Research during the late fifties and into the 1960s , because by 1966 AR had 32% of the entire domestic loudspeaker market. In later years, of course, as the product excellence and innovation of AR declined compared to the overall competition, and market share dropped accordingly. By the time Teledyne took charge in 1967, efforts were made to completely change the marketing philosopohy, but it was not enough to end the decline in market share. In the AR case study done at Harvard's Business School back in the 60s, AR's dealer relations were described in the early days almost "as a lack of relations." AR did not solicit new dealers, but depended mainly on consumer demand to stimulate dealer interest in AR products. Importantly, AR did not maintain close relations with dealers or favor particular dealers, and AR granted all dealers -- "old and new, large and small" -- the exact same discounts. It permitted dealers to set their own prices and to reduce prices below "suggested retail" if they wished. According to AR, the requirements were that a dealer (1) had to purchase a few of each model speaker being made at the time, (2) had to have a competent diaplay and demonstration ability in conjunction with high-quality electronics, (3) had to pay their bills promptly and (4) the dealers were not allowed to act as "middlemen" to transship speakers to unauthorized dealers.

--Tom Tyson

[tysontom]

Speaking of Dynaco, I took my first Dyna PAS-3X preamp and Mark III amp to the McIntosh Clinic in 1967, and both units were tested by O'Brien (see attached file) and performed relatively well. The next year, same time I took my AR amp for test, I took my two well-worn (and probalby out-of-bias) Mark IIIs in for another test. This time they did okay, but distortion was up quite a bit (see attached files).

--Tom Tyson

Some of these Dynaco PDF files are out of sequence -- my mistake. Here is (I hope) the correct 1967 test of the Dynaco Mark III:

--Tom Tyson

[genek]

You describe how the dealers were different; i.e., the only good dealer was selling every brand, and I follow you on that. But you didn't describe how the Mac Clinic was different. How was it different?

I doubt that the McIntosh-run part of the clinic was any different at all.

It was simply that the dealer and his salespeople didn't trash other brands because they were selling most of them as well.

[tysontom]

I doubt that the McIntosh-run part of the clinic was any different at all.

It was simply that the dealer and his salespeople didn't trash other brands because they were selling most of them as well.

genek,

I understand what you are saying now. I agree that these dealers that did sell multiple brands were less likely to "bad mouth" those brands that they had in the store. However, I think that many of the McIntosh dealers, and those that sponsored the clinics, tended to be arrogant and snobish at times, and freely disparaged other products brought into the clinics. Dave O'Brien and the McIntosh employees were more discreet and professional, and rarely said anything negative about competitive products, even though you could see disdain on their faces when testing some equipment.

--Tom Tyson

[genek]

Dave O'Brien and the McIntosh employees were more discreet and professional, and rarely said anything negative about competitive products, even though you could see disdain on their faces when testing some equipment.

Were an AR amp and Dynaco kits really "competitive products" to McIntosh's amps? Especially after the 20-30% dealer discount off the AR? I would think it would have been like roadtesting a Corvette and a couple of dune buggies vs. a Lincoln Continental. Performance plus bang for the buck vs. performance plus luxury.

[ar_pro]

It's unlikely that McIntosh lost much business to Dynaco - ever.

It's possible that some of Dyna's earlier tube designs presented a ball-park alternative to McIntosh, but certainly not their transistor stuff.

The deciding factor was always the customer's wallet - for the most part, people who could afford McIntosh or Marantz simply didn't spend money on Dynaco.

[tysontom]

It's unlikely that McIntosh lost much business to Dynaco - ever.

It's possible that some of Dyna's earlier tube designs presented a ball-park alternative to McIntosh, but certainly not their transistor stuff.

The deciding factor was always the customer's wallet - for the most part, people who could afford McIntosh or Marantz simply didn't spend money on Dynaco.

I think ar pro makes some great points here: overall, Dyna didn't affect McIntosh's overall sales particularly, but companies such as Fisher and Scott were probably more competitive with Mac in the early days of hifi. Yet, by the mid 1960s, Dynaco was a major force in the high-quality, low-price segment, and amps such as the Stereo 70 and the Mark III (despite the relatively meager peformance of my two out-of-spec units) gave performance that was on a par with amps such as the McIntosh MC-60 and MC-75, as well as the Marantz 8B and Model 9. AR could have easily used McIntosh amplifiers for their live-vs.-recorded performances, but instead chose the Dynaco Mark III. On the "business" end of the recording, however, there was no compromise whatsoever in that AR used a top-of-the-line Ampex 351 professional stereo 2-track recorder and Sony and similar condenser microphones, to make the recordings. What this said was that AR felt that Dynaco (also a co-sponsor of the concerts, too) amplifiers could match the performance of any other amplifier.

McIntosh had a specific niche in the market place, and remarkably they have basically held on to that same philosophy even to this day while such companies as Dyna, Scott, Fisher, Marantz and other "greats" of the era have faded into distant memory. Ironically, there are several amplifiers that can easily outperform most of the Mac amps in all-out performance; and there are many people who will say they prefer the sound of this amp or that amp, but basically when an amplifier produces a stable output at distortion levels below 1% across the spectrum, and another amp does the same thing, one's ears will be very hard to distinguish the difference.

--Tom Tyson

[genek]

there are many people who will say they prefer the sound of this amp or that amp

I'm definitely not one of those. Turntables, yes, phono cartridges and speakers, absolutely. But I've bought a number of amps, tuners and receivers over the years based entirely on their specs (the main spec for amps being do they have enough power and will they run my speakers safely) and have never found myself wishing I'd made another choice after listening to them for a while.

[Guest MikeP]

In the '80s I lived in Alaska. I bought a lot of equipment from Pyramid Audio in Anchorage, an absolutely superb shop at the time.

They had a Mc clinic going on one day when I visited the store and a lady from out in the bush brought in an old amp from the early 50's. It wasn't working. The clinic guys repaired it internally on the spot and installed a new power cord and tubes, tested/adjusted it, all at no charge, and it met it's specs. I did not own any Mc equipment at the time but it was far and away the best advertisement (without any advertising!) for a company I have ever seen.

[tysontom]

Hi there;

I was never at a Mac clinic but there was two rumours flying around here in Vancouver at that time period.

These were from non-AR supporting and non-Mac stores.

1. Some Mac speakers used the AR-3A drivers, was told to me at the Vancouver Hotel 1971 HI-FI show.

2. Mac clinics would not test the AR amp as they caught fire.

Isaac Hayes', "Shaft," was the record cut of choice by almost all displayers, LOUD.

The typical comment's from local non-supporting AR dealers was that the amp caught fire and the AR turntable used a common drugstore elastic band to drive the clock motor.

We all know how inaccurate rumours can be sometimes.

Vern

Hello Vern!

I love your comments above, reflecting the rumors and comments that were so often made about hifi equipment (especially AR) back in the 60s and 70s! My take on your items # 1 and 2:

1. This is definitely untrue. McIntosh never used AR drivers for their speakers although Roger Russell (McIntosh speaker engineer) used an AR woofer and AR-3 tweeter for a prototype speaker he made for himself once. However, McIntosh did use a 2-inch soft-dome tweeter patented by Bill Hecht, and this tweeter was also used by (and designed for) Avery Fisher for his new XP-4A speaker, a so-so speaker designed to compete with the AR-2a and AR-3. The 2-inch Hecht-designed soft-dome tweeter was not a particularly good performer, as Roger Russell reports out on his website, and McIntosh went on to re-design this tweeter and even get a patent on the new design! Coincidentally, Ed Villchur made prototypes of 2-inch soft-dome tweeters by using a treated-cloth dust cap from an AR-1 woofer, but he reported that the performance was poor compared to the hard-dome phenolic material that he eventually used with the AR-3. The soft-dome tweeter was more efficient, but the phenolic dome tweeter had superior dispersion and smoothness.

2. This is both true and untrue. McIntosh Clinics tested AR amps, and did so many times. AR amps would catch fire (well "smoke," not burn), and did so many times due to the egregious bias problems that were encoutered in some early versions. The bias problem was pretty much corrected, but there were still several reliability problems with AR electronics.

Images: (1) Fisher XP-4A, (2) Hecht Soft-Dome Tweeter, (3) Hecht Soft-Dome Patent, (4) McIntosh Soft-Dome Patent

--Tom Tyson

[dynaco_dan]

Hello Vern!

I love your comments above, reflecting the rumors and comments that were so often made about hifi equipment (especially AR) back in the 60s and 70s!

--Tom Tyson

Hi Tom;

I always enjoy reading your write-ups, Tom.

I was looking at the 3 way speaker photo in particular, Tom.

Does the woofer have a speaker cone made from an aluminum pie pan?

Would this have been a speaker known as, "woofer a la mode". LOL

Vern

[tysontom]

Hi Tom;

I always enjoy reading your write-ups, Tom.

I was looking at the 3 way speaker photo in particular, Tom.

Does the woofer have a speaker cone made from an aluminum pie pan?

Would this have been a speaker known as, "woofer a la mode". LOL

Vern

Vern, the 3-way speaker shown in the photo is the Fisher XP-4A, and actually the entire speaker was designed by Bill Hecht as I recall. The midrange drivers should be familiar: they are the Carbonneau 4-inch jobs similar to those used in the AR-2. That woofer was very unusual in that a shelf was built inside the cabinet to hold the woofer magnet in place, and the cone was a concoction of a section of "pie-pan" aluminum and paper cone. Why all this was done is not clear, but the designer felt that he had a superior design. The speaker was actually quite popular, and I believe it received good reviews from the critics.

--Tom Tyson