REFERENCE COMPONENTS

COINCIDENT PURE REFERENCE EXTREME SPEAKER

UPDATED MARCH 2014

INTRODUCTION

PART ONE- MY PERSONAL SPEAKER "REFERENCES" (1972 to Present)

PART TWO- THE ("ORIGINAL") PURE REFERENCE'S PERFORMANCE - "THE FUNDAMENTALS" & "THE BASICS"

PART THREE- AMPLIFIER REQUIREMENTS

PART FOUR- LISTENING ROOM REQUIREMENTS

PART FIVE- OPTIMIZING MY SETUP

PART SIX- SONIC COMPARISONS

PART SEVEN- PRICE COMPARISONS

PART EIGHT- CONCLUSION

PART NINE- FURTHER REFLECTIONS A YEAR LATER

PART TEN- THE "EXTREME" VERSION

PART ELEVEN- "THE DOUBLE" EXTREMES

ADDENDUM- BI-AMPLIFYING THE (DOUBLE) EXTREMES

ADDENDUM TWO- 2011 SYSTEM PERFORMANCE UPDATE

INTERNAL LINKS

INTRODUCTION

The Coincident Pure Reference Extreme (PR) is the finest speaker I have ever heard overall. It has finally replaced my 10+ year "reference", the Ars Acoustica System Max. These two speakers are very similar in basic design philosophy, though their execution is quite different, mainly due to a decade's worth of improvements in (dynamic) driver technology. The PR is also unusually "practical": It is "flexible" in the choice of both amplifiers and listening rooms.

Since I obviously don't change my personal references very often, I feel it is necessary to discuss my basic philosophy on speakers. This will include the long-term history, and evolution, of my personal speaker references, plus the specific and detailed reasons why the Coincident Pure Reference has achieved its current status.

Important Note- The first nine "Parts" of the below review were about the "original" Pure Reference, which came out in late 2007. The "Extreme" version came out in late 2009 (Part Ten). It subsequently became my new "Reference". In spring 2010, I "doubled up" the Extremes, and this became, and still is, my current "Reference" (Part Eleven).

PART ONE- MY PERSONAL SPEAKER "REFERENCES" (1972 to Present)

I've personally owned (let alone my former store) countless speakers in the last 36 years. However, most came and went quickly, and it is only the speakers below that were my true primary speakers (or "References"). The dates are as good as my memory can provide:

1972 to 1974- Original Quad ESL-57 Electrostatics (stock)

1974 to 1977- KLH Nine Electrostatics Doubled (Two speakers per channel-side by side in a "V" shape)

1977 to 1982- Original Quads (Modified) with RTR ESR-15 Electrostatic Tweeters, and later with various subwoofers

1982 to 1985- Strathearn Ribbons (3 stacked as a line source) with various (sub)woofers

1986 to 1989- Martin-Logan Original CLS (Modified) with Entec subwoofers

1989 to 1996- Wilson WATT (Modified) with (stacked) Entec and (later) Tympani (sub)woofers

1997 to Present- Ars Acoustica System Max (with their own subwoofers)

Details and Explanations:
1. I went back to the Quads in 1977 because the (otherwise superior) KLH Nines had buzzing wood frames and unreliable transformers.
2. The Quad's front and back protective grilles were removed, the speaker raised 18" and the crossover capacitor was replaced.
3. The CLS had a 9" taller frame, shorter internal wiring and improved passive parts.
4. The WATT's two drivers and internal crossover were all replaced.
5. The years 1977/8, 1985/6 and 1996/7 were all "transitional", with no direct exchange of references.

At a quick glance, these six speakers appear to be very different from each other, but there is a basic design philosophy with two critical commonalties.

1. Since 1979, the use of subwoofers (to get the last octave and to also bi-amp and clean up the midrange).
2. The subwoofers withstanding, all of the speakers were either one or two ways.

In practice then, my reference speakers were all, at least in design theory, relatively "full-range" and "cohesive".
When using more common terms, the goals of my two design priorities were very simple:
1. I wanted to hear all (full-range) of the music, and
2. I wanted to hear this music from (ideally) only one "source"* (driver).

*Analogy- Even the most highly skilled "duo" can't exactly imitate a "soloist".

Accordingly, it is now easy to understand why I have avoided, and even ignored, so many different speakers, from so many different companies (including earlier Coincident models), no matter how excited other audiophiles felt about them. From my perspective, if the speakers didn't conform to my two basic design requirements, they were effectively irrelevant, because I knew, from decades of direct experience, that they could never satisfy me, no matter what other sonic strengths they possessed.

Of course, these six reference speakers also share actual performance attributes, especially compared to their many competitors:

1. They are all fast and detailed, particularly the electrostatics and ribbons in the midrange.
2. They are all clean, with low distortion, particularly at low and medium volume levels.
3. They are all relatively neutral, particularly the Quad, Wilson and Ars, though all of them have some colorations.
4. They all have a low "sound-floor", with the Ars being the best of the bunch in this area.
5. They all have a "live" and "immediate" sound.

They also have some noticeable problems, many of them which are shared:
1. None of them can play "really loud", and the Quad is particularly limited in this area.
2. The "imaging" capabilities are mixed, with only the Strathearn, Wilson and Ars being really good in this area.
3. Related to #1, they all compress the loudest dynamic swings, especially compared to the better horns.
4. The subwoofers were difficult to integrate, especially with the dipoles, but I was (very) successful with the Wilson and Ars.

Still, looking back over more than 35 years, I feel I made the right choices at the time, considering what was available. I heard and tried out so many speakers; in my homes, in my store, at audio shows and in other audiophiles homes. I even had "hybrids" that I configured myself, but none of these innumerable speakers could satisfy me, in the long-term, as well as my above "references".

When assessing my personal "Evolution", the most recent (dynamic) speakers had fewer "noticeable" problems; In general, while they retained almost all of the strengths of the earlier references; They were a little more neutral; with a lower sound-floor; with a larger soundstage along with superior image focus; had better subwoofer integration; and the ARS finally had the (important and critical) capability of being amplified with the finest, low-power SET models. In practical terms; they drew less attention to themselves.

So now the Coincident Pure Reference joins this ultra-tiny group, and these are the reasons why...

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PART TWO- THE ("ORIGINAL") PURE REFERENCE'S PERFORMANCE

"THE FUNDAMENTALS" & "THE BASICS"

"The Fundamentals"

The PR is a simple two-way speaker, with a (built-in) subwoofer. It is the most highly evolved example I've heard of this very specific genre of speakers.

Why and how: The PR's "parts", and its execution, elevate its performance to "outstanding". This is in stark contrast to the numerous other speakers which also share its basic design, and yet mainly remain "mediocre", with the usual exceptions of "better or worse".

As for the details, I will begin by focusing on the two basic design "fundamentals" discussed above. First will be "cohesiveness", which is, by far, the more difficult of the two to achieve.

Cohesiveness

The PR's single midrange driver obviously eliminates the main problem of "hearing two different sources". However, there are still other (potentially serious) design problems to avoid, and most speakers fail at solving them. These design challenges are:
1. The midrange to tweeter transition,
2. The midrange to (sub)woofer transition,
3. The more subtle problems of various, audible changes within the midrange itself (to be discussed later in Part 2).

I spent many hours, particularly in Toronto, listening specifically for transitional problems. I used every musical (LP) test and hurdle I could think of (strings, voices, woodwinds, piano, organ etc.). I eventually came to the conclusion, later verified by what I heard in my own system, that the Pure Reference is superior or equal to the finest speakers I've heard at each of these two transitions.

The three best speakers I've heard at handling the critical midrange/tweeter transition are the original Quad (for its time), the Morrison(s) and the Avantgarde Duo. Meanwhile, the Coincident Total Victory II (TVII) and the Ars Acoustica System Max are the two best I've heard with the midrange to subwoofer transition (which is one of the reasons why the Ars was my reference for so many years). The Pure Reference equals each of these five speakers in their respective transitional strength. This accomplishment, excelling in both (or all) transitions, is unprecedented in my experience. To be more specific...

The PR noticeably beat out the Ars in the critical midrange/tweeter transition. This superiority was most noticeable with violins and sopranos. While the Ars is still "excellent" at this transition, the PR is as close to a "single-driver" as any two-way I've heard. The TVII, for its part, has two transitions in the midrange, which automatically disqualifies it.

Next, both the Quad* and the (stock) Duo have serious problems* with their midrange/(sub)woofer transition, the Morrison less so. The Duo may work well with their Basshorns, but this solution entails both a huge monetary expenditure and highly unusual room requirements. As for the Quad, I know of no one who has successfully mated a subwoofer with it, including myself, and I spent years at it. The Morrison goes pretty deep, and it's also "fast", but it's also dynamically limited, presenting a unique matching challenge. (*As do all the other "dipole/dynamic woofer combinations" I've heard.)

Ironically, the better the performance of a particular speaker in the midrange (especially in "speed"), the greater the challenge it is to match that same quality in the bass (which will then help "hide" the transition). That is why some speakers, like the Quad, are so fiendishly difficult to optimally transition with a subwoofer.

In short then, the PR sounds more like a full-range one-way speaker ("The Ideal") than any full-range two-way dynamic speaker I've ever heard, at any price (with the Morrison coming in second).

In fact, the only speakers that have any advantages in "transitions" are a few dipoles with no transitions. Examples are the largest Sound Labs and Acoustats, or custom "hybrids", such as the Martin-Logan CLS*/Tympani woofer combination. However, as far as I know, none of these speakers is truly "full-range", in the traditional, flat to 20 Hz sense of that term. Worse, virtually none of them are flat to 20 Khz either. (*The Quad can also work with the Tympani, but there are severe dynamic discontinuites.)

This then brings us to the second design fundamental; "Full-Range".

Full-Range

The second design "fundamental" is being "full-range". This has not been a serious design challenge for many years, actually decades now. It's mainly a matter of cost and proper execution, particularly for achieving the bass part of the equation (20 Hz). To again be specific:

The Pure Reference goes as deep as any speaker I've heard (the quality of the PR's bass will be discussed later). The only speaker I'm aware of (but haven't heard) that can go truly and noticeably lower is the Eminent Technology Model 17 Subwoofer, which can not transition to a midrange driver. This makes it of academic interest only within this context.

As for the high frequencies, the Pure Reference is flat to beyond 20 Khz, and it sounds like it. It takes a true "super tweeter" (usually the finest ribbons), or the Acapella Ion Tweeter, to "sound" even more extended. Unfortunately, I have not heard any speaker using any of those advanced tweeters that did not have noticeable transition problems. To summarize the above then, and by strict definition;
The Pure Reference is the most cohesive of the truly full-range (20 Hz to 20 KHz) speakers that I've heard.

And now it's time to discuss all the standard and familiar performance requirements, and their related engineering challenges. They must be met, and overcome, before a speaker can be honestly described as "an outstanding reproducer".

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"The Basics"

Important Perspective- I may have given a misleading impression of my audio priorities, which must be dispelled:

Despite my intense focus on "Cohesiveness" and "Full-Range" in both "My Personal Speaker References" and the discussion above, these two parameters were not what I listened for when I first heard the Pure References in Toronto in October 2007. Before I get into the actual performance details, I must explain exactly what happened that first evening...

When arriving at Israel Blume's home, I thought I would be listening to the Total Reference, his new "flagship", which I had never heard. To my great surprise, I saw a different speaker, which Blume had never told me about (or even hinted at). So, for the next 6 hours or so, I listened to this "mystery speaker". Blume played CDs for the first 30 minutes as the system warmed up. After that, he only played records, many of which were at my specific request. At that time, "transitions" never entered my mind. Instead, as I always do at first, I focused on "the basics": Neutrality, sound-floor, dynamics, immediacy, purity, image size and overall (gut) naturalness etc.

I soon had an extra reason for doing so: A strong sense that I was hearing a speaker which had a combination of sonics strengths I had never experienced before. I had to know, ASAP, whether my gut feeling was correct or not, which is why I was almost manic that evening in my musical requests. By the end of the night, I had satisfied myself that I had indeed heard something truly "special". Then, in the following days, along with "confirmation", I made an intense focus (30 hours) on what most people would consider "subtleties", but experienced audiophiles know that it's those important details (like obscure legal details in contracts) that will make (or kill) the final deal.

So, after reversing my traditional order of focus within this essay, I want to finally concentrate on "The Audio Basics", and methodically compare the Pure Reference's performance to the best speakers I've ever heard, category by category. First up isn't much of a surprise...

Neutrality of Character- The Pure Reference is as neutral as any speaker I've ever heard (and more neutral than any I've heard using a wood box). Is it "the most neutral"? Maybe, but I honestly can't say that without hearing all the other most neutral speakers at the same time. For perspective, these are "the other most neutral speakers" I've ever heard (all of them now discontinued!): The KLH-9, (Original) Quad, the Ars Acoustica System Max, the Eminent Technology LFT-3, Coincident Victory II and Total Victory II. Plus, there are invariably other speakers just as neutral that I can't think of at this time. (Such as the Original Apogee, but the amplification is ultra-critical.)

All these speakers have this in common; Because of their minimal (cabinet and driver) resonances, which are the "keys" to neutrality, they have a "character" which is difficult to describe, especially in words, for it is relatively subtle. Most attempts are useless or even ludicrous ("chocolate"). Accordingly, I will not attempt to do so, other than stating that the PR comes as close as any speaker I've heard to having no character to even describe. While I do hear a slight emphasis in part of the upper bass, it is too subtle and elusive to "characterize", because it can change, for better or worse, depending on the amplifier, crossover adjustments and room placement. Further...

I believe "neutrality" is somewhat different than other sonic attributes, not only due to its vital importance, but because the issue of "relativity" is less relevant here. By this I mean that when a component is described as "neutral" (without serious resonances), it's more "absolute" than simply saying that it's "detailed". This is because we don't know how much detail is actually potentially available to reproduce. However, "neutral is neutral", and once a component honestly achieves that distinction, it's inconsistent to challenge this later, even if higher performance levels are eventually attained. The proof I offer is that even some vintage components, originally described as "neutral", are usually still considered the same way today.

Finally, I "sense" (and only sense) that the PR may have fewer "mini deviations", from perfect neutrality, than the other speakers. This is different than the broad variations usually associated with this term, which are also much easier to hear. It will take time and/or measurements to find some real proof of this sense, one way or the other. My thinking is mainly based on the superior performance of the ceramic drivers that are used in the PR. They may have fewer deviations than the drivers in other (dynamic) speakers, so even if a speaker, such as the Ars Acoustica System Max, has even less noticeable cabinet resonances than the PR, the System Max should still have slightly more noticeable overall deviations. I realize this may be all quite subtle, but still noticeable, so it must be at least mentioned.

Immediacy- The Pure Reference is the most immediate dynamic speaker I've heard. Just as important, and rare in my experience, the PR is equally immediate throughout virtually the entire frequency range. However, the most immediate speakers I've ever heard, with no qualifiers, are the Martin Logan CLS, the (1990s) Audiostatics and the Avantgarde Duo. I don't have any of these speakers available for a direct comparison, but I've heard the first two extensively, and based on my memory of them, the PR is not as immediate as either electrostatic, but it does come extremely close to matching the (horn based) Duo. In fact, I'm not sure I can make a confident distinction between them based on memory.

While the gap is "noticeable" between the PR and the two electrostatics, it is not "dramatic". This is because I believe the gut reaction of most audiophiles, hearing the PR for the first time, will be the same as mine: "This speaker is immediate"*. In fact, the PR comes closer to sounding like a good electrostastic (in their strengths) than any dynamic speaker I've ever heard. So, while the PR may be, or is, at the highest level of immediacy within its dynamic speaker group, and it should obviously be considered a "strong suit", I feel it still does not quite match the best of the entire speaker universe.

Further- One of my associates has owned the CLS for years now, and he even recently replaced the panels. He visited me for a couple of days in mid-February 2008, on his annual visit. We spent many hours listening to the PR. I played some records he specifically requested, which he had recently heard on his own speakers. The "big question" to him: How close is the Pure Reference to the CLS in the areas of "Immediacy and Speed"? His answer: "Very, very close."

*Examples-
Martin Codax-Cantigas De Amigo-Criswick-HARMONIA MUNDI HM 1060
BRAINSTORM (SOUNDTRACK)-HORNER-TER 1074/VARESE SARABANDE STV 81197

Cleanness and Purity- The results here are similar to "Immediacy" above, though not quite the same. The Pure Reference is very clean and pure. It is equal, or superior overall, to any dynamic speaker I've ever heard (though the Ars Acoustica is close, and maybe even better at some bass frequencies).

Still, I don't think the PR matches the best electrostatics at low to medium volume levels. However, the PR is noticeable superior to these electrostatics at higher volume levels and in the deep bass. This also means its "sense of purity" doesn't (noticeably) change as the volume or frequency changes. So I give the edge in overall purity to the PR when compared to the electrostatics. This doesn't complete the purity picture though...

When you compare the Pure Reference to the Avantgarde Duo (stock), the Duo will have a slight edge at extremely high (and even dangerous) volume levels (and maybe lower levels), but the PR will have an even more noticeable advantage in the entire bass range (below 200 Hz), and at all volume levels. So I once again give the overall edge to the PR. Still, there are a few even more imposing "challengers"...

There are the large dipoles, mentioned earlier, the big Acoustats and Sound Labs, plus the (rare) Original Apogees. They are not quite as ultra-pure as the CLS or Audiostatic at low to medium volumes, but they are cleaner at higher volume levels, and also in the mid and deep bass. I would say they have an edge over their two smaller rivals, but are they the equal of the Pure Reference? I would say it's too close to call without direct comparisons, because all of these speakers have basically the same important strengths across the board, and virtually no noticeable weaknesses, in this area.

In short, the Pure Reference is as clean and pure as any speaker I've heard, when all volume levels and all audio frequencies are taken into consideration .

Speed and Outer Details- Once again, this parameter is similar to "Immediacy" and "Purity", with the same two names as my "References"; The Martin-Logan CLS and the Audiostatics (now you know why these two speakers are among the very few in my Reference File). As above, the Pure Reference comes close, but does not quite match their performance in these areas. The PR is fast alright, faster overall than any dynamic speaker I've heard, and even "feels" like an electrostatic in its lack of obvious slurring, but those two fastest electrostatics still have a sense of instantaneous reaction that I've never heard equalled by any other speaker, even including the original Apogee.

This "starting" and "stopping" advantage also allows them to maximize the reproduction of outer detail. In practical terms, it is this ability that enables the speaker to be "intelligible", which, in turn, allows the listener to hear each individual note (or word) without an artificial smear. The PR is superb here for sure, but it's not "the best".

Important- The Critical Distinctions of "Detail"

Many audiophiles have a problem making a distinction between a component's ability to reproduce "outer detail" and "low-level information" ("inner detail"), which I discuss below. They think it is the same thing. It isn't. If a component can reproduce outer detail, but not inner detail, that component will sound "sterile" and "analytical". Many transistor amplifiers have this problem. To make a visual analogy...

It's like the difference between looking at a forest in Summer, and the same forest in Winter. Yes, the analytical component, with only outer detail, will allow you to see more of the trees in Winter, but that's only because the leaves and foliage are all dead and gone. That's a heavy price to pay, which is why many audiophiles prefer tube electronics, and other components which minimize this problem.

High Frequency Reproduction- The finest tweeter I've ever heard is the Acapella Ion TW 1S, but it can only go down to 5K, and even then only under certain circumstances. Still, from around 10K and above, it is "the best", and approaching "perfection". For the more traditional (and practical) frequencies, 3K and above, the best tweeters I've heard are all ribbons. Examples are the outstanding ribbon tweeters in the Coincident (Total) Victory (II) as well as the Magnepan Tympani series.

So what about the Pure Reference's tweeter? It's the best dome tweeter I've ever heard. It's superb** in every area; speed, purity, smoothness, extension, lack of homogenization and (vitally important to me) it has an ultra-low sound-floor. However, it obviously doesn't match the Acapella within their shared frequency range.

The remaining question I have is when comparing the PR's tweeter to the finest ribbons I've heard. I feel, at this time, that the ribbon in the Victory II has a slight advantage over it. I would like to make a direct comparison between them one day. However, this speculative tweeter "shootout" can never be anything more than an "academic exercise", because no matter what the results of this comparison are, it is very important to keep this critical perspective...

At this highest level of audio performance, matching the tweeter to the midrange (and vice-versa) is usually even more important to the final sonic results (and much more difficult to achieve) than the isolated and independent reproduction of the two drivers themselves. In other words, if a superior ribbon tweeter replaced the dome tweeter currently in the PR, the overall results would most likely be a serious disappointment (See Part 1). Why? There would be a discontinuity between the two drivers that would be even more noticeable than the slight deterioration in the high frequencies.

This is why simply designing a speaker with the best available woofer, midrange and tweeter (if that's even technically possible) would not automatically create the best overall performer.* Further, evaluating a speaker by only focusing on the "lows, mids and highs", independently of each other, is also dangerously incomplete and usually highly misleading.

*For an analogy, imagine a relay race with one team having the four fastest runners, but one of them almost always drops the baton. I would instead place my bet on another team, which will not be as fast individually, but will practice perfecting the handoffs, so none of them ever drops the baton.

**Examples-
RAN-TAKEMITSU-FANTASY FSP-21004 (the most intense flute-like sound I've ever heard)
LA SPAGNA- ATRIVM MVSICAE DE MADRID/GREGORIO PANIAGUA- BIS LP-163/64

Low Frequency Reproduction- Even though we are only focusing on the (3 octave) frequencies between 20 Hz to around 160 Hz (deep, mid and upper bass), there's still no one speaker I've heard that is unqualifiedly "the best". (And if we consider the ultra-deep bass, below 20 Hz, only one speaker, the Eminent Technology Rotary subwoofer, is even viable.) These are my bass references (prior to the arrival of the Pure Reference):

Mid-bass and Upper-bass (40 to 160 Hz)- The Original Apogee (with the Tympani IV bass panel receiving a well deserved "Honorable Mention")

Deep Bass (20 to 40 Hz)- Concentric Speaker Technology Super Sub

Complete Bass Range (20 to 160 Hz)- Ars Acoustica Gravitas Subwoofer (By default, since the other two speakers can not reproduce the entire bass range)

Explanations:
1. The Apogee would be "the best", without qualifications, except that it doesn't reach into the the low/mid 20's. The Tympani IV "dies" even earlier, at around 30 Hz. They are both outstanding in the same areas; Impact, definition, immediacy, control and linearity.
2. The Concentric has superb weight, detail, control and power, but the quality deteriorates above 50 Hz.
3. The Gravitas has all-around excellence. It can't play "real loud", and it doesn't have the definition or impact of the two big dipoles, but it's still excellent in those two areas.

Both the Apogee and Tympani have the same problems, with the Tympani's being more obvious. Because they require a lot of power/current (which means complex/inferior amps) and they also don't go "real low", there have a certain "dry quality", which doesn't allow the size, scale and decays of the recording space to be heard or sensed (especially at low volumes). This weakness will be inconsequential to many listeners, but to lovers of acoustical music (such as myself), this may be a serious problem. I prefer the Ars, overall, because its problems are more "relative", and not as noticeable in the long-run. Now, what about the Pure Reference's bass...

It is very similar in quality to the Ars Acoustica, though I feel the PR has a very slight edge. Further, the PR has more weight, impact and sense of scale, and it even goes down a touch lower. This means, in effect, it is as at least as good, or better, than the Ars in every bass parameter. However, the PR requires more care to optimize than the Ars, because of its single cabinet and larger woofers.

Accordingly, the PR is now my new "reference" for low frequencies, even though it is not "the best" in every way. So while the PR will never match the Apogee in its greatest strengths, it will come closer than any other dynamic woofer system I've heard, and at any price.

Also, please remember the perspective I provided earlier for the "High Frequencies": The cohesiveness of the bass to the midrange is still more important than the bass frequency performance in isolation. It is the same case here, though not nearly as difficult to achieve.

Finally, I have one highly subjective (and extremely difficult) test that has never failed me in evaluating the bass reproduction of speakers.
The Test: Can the speaker's bass "Frighten Me"*? (Or "Threaten", in contrast to just "overwhelm".)
If it can, that means the speaker is not only going truly deep, but also with power and with control**. It takes all three qualities to pass this test.
The results: The Pure Reference passes this test.

*The exact opposite (or complete failure) of this test is bass that is "comical" (or "flatulent"). Think of a graceless, ponderous image with the accompanying sound of a tuba, Sousa Horn or contrabassoon. This is a complete contrast from "threatening".

**Examples-
STRUNZ&FARAH-MISTERIO-BURABAMPO (SIDE TWO)-WATER LILY WLA-CS-08
OREGON-ECM 1258 (SIDE ONE)
EVIL DEAD-VARESE SARABANDE 81199 (SIDE TWO)

Separation of Instruments (and Lack of Homogenization)- This area is directly related to "speed and outer detail" previously discussed above. Further, it is also seriously effected by two other performance parameters; "imaging" (coming later) and "volume changes". So "excellence" in this one area thus requires excellence in all three areas at the same time. It should be no surprise then why I consider this parameter to be so important in evaluating overall performance and also why it's so difficult to master.

It's critical importance for appreciating music is a "no brainer". It's obvious that hearing all the musicians, and all the notes, all the time, no matter what else is happening, must be one of the highest priorities for audiophiles and music lovers. Contrast this ideal to the alternative, unfortunately the norm, of a musical "soup", where all the musicians, and all their unique relationships, are compromised.

There are plenty of speakers that can achieve one or even two scores of "excellence" (look above for examples), but it's very rare to find a speaker excelling in all three. The Ars Acoustica System Max is one of them, though only barely, because it is marginal in both "speed" and "volume changes". Another successful speaker is the MBL 101. I don't like the MBL for other reasons, but this important area is its "strong suit", probably the best I've heard, and the main reason for many audiophiles' admiration of the design. Some of the Wilson speakers are also contenders, similar to the Ars. So, why aren't there more speakers who score the "Separation Trifecta"?

The problem is combining speed and imaging (phase accuracy), which are relatively easy to achieve at lower volumes, with the almost directly contradictory achievement of clean (and unchanging) high loudness capability. The same drivers that excel at low volumes almost always become strained at high volumes, with the result being a noticeable homogenization. To experience this phenomena, just listen to a well recorded orchestral work with both varying soft and loud passages. Most speakers begin to homogenize at a certain volume point. Still, what about all those (usually large and expensive) speakers that use multiple drivers, and can play really loud?

It's true that most of these speakers don't change for the worse with higher volume levels, but this "advantage" usually comes with a highly ironic price: Their INability to adequately separate the instruments (and notes) at lower (normal) volume levels. So the fact that they don't noticeably change with volume is ultimately irrelevant, since they were "failures" at separation (and detail retrieval) before the loudness test even began. (This is the cost of complex designs.)

So now we must evaluate how the Pure Reference performs in this almost impossible to master parameter.

I'm happy to report that the Pure Reference excels in "Separation", and at both low and high volume levels. It's very similar to the Ars, but it's even more detailed and it changes even less at higher volumes. In fact, I haven't heard any deterioration at high volumes, either in Toronto or in my room in Florida. I play pretty loud at times, though I always try to keep it "realistic". When the PR is compared to the MBL, it's a mixed bag. The MBL is equivalent in detail and loudness capability to the PR, but has more potential for "imaging" if it can be set-up correctly. The problem is that "if", because the MBL is only at "its best" in certain large rooms. Otherwise it's no better that the PR, and could be even worse.

In short, both speakers are outstanding, but there can be no clear-cut winner because the MBL's performance is room dependent. Bottom Line- While the MBL can achieve the highest possible score, the PR will score as high, or higher, in most rooms.

Image Size and Focus- My standard for this category has been the same for more than 30 years; The Morrison Speaker (originally the Hegeman). It is a two-way omni-directional, with a large, yet totally natural, image size, and with amazing focus. The image size has since been matched by a number of other speakers (such as the Ars Acoustica and some line sources), but while the Morrison's focus has been approached over the years, it has never been equalled in my experience. I haven't heard any of the contemporary versions of this speaker for something like 15 years now, but I am very familiar with the 1980's versions, because I was a Morrison dealer for a number of years (He sells direct now).

I heard the Morrisons in every listening room of my store and apartment, plus in numerous customers homes. They weren't easy to set-up, and they imaged at their very best only in a large room, which created a dilemma, because they couldn't really play that loud. Still, they are my reference, and I would say the closest I've heard any speakers matching them, overall, are the (second place) MBL and the above mentioned Ars Acoustica. So how does the Pure Reference fit in to this picture?

The PR, at a minimum, equals the Morrison, and any other speaker I've heard, in image size. In fact, it may even have a unique advantage in this regard. Not because it is bigger than the others "at its best", but because it is truly big even in a medium size room with a low ceiling. When I heard the Pure Reference in Toronto, the room had a lower than average ceiling height. Despite this, I still heard a "huge sound", something I've never experienced before in a room with a low ceiling, and I've literally heard hundreds of good systems in rooms with a similar disadvantage. Compared to the Ars Acoustica, in my own present room, the image size is very similar, but I believe the "sense of scale" (meaning image height in this instance) slightly favors the PR. In short, image size is about as good as it gets with the Pure Reference. What about focus though?

Unfortunately, the Pure Reference does not equal the Morrisons in focus. Actually, I don't even think it is possible for any speaker to equal the Morrisons, unless its design is basically replicated. In short, I believe a properly designed omni-directional will have an advantage in focus compared to every other type of speaker design, no matter how well it is executed. Because of this, it is understandable that, for some audiophiles, an omni will be the only type of speaker they can live with, regardless of any other considerations.

Now, what about the PR versus the Ars Acoustica in focus, which is also a virtual "point source"? They are similar once again. However, the Ars still has an easily noticeable advantage. In fact, this is the one area which I definitely prefer (and miss) the Ars compared to the PR. The Pure Reference then is definitely "excellent", or at least "very good", in image focus, but it's not equal to "the (or second) best".

Tonal Consistency- This is a new category for me, which I don't think I've ever discussed in the past, and I may have difficulty in trying to describe it. In fact, it took the Pure Reference's unique capabilities in this category for me to even think about it, and later coin the term*. Tonal Consistency is more than just being "smooth" (meaning having a linear frequency response) or "neutral". I believe TC is a combination of being both linear and harmonically complete (without distortion) at the same time, and, even more, all of the time.

TC is more than the different notes sounding like they're all being treated "equally", so no single note is emphasized or de-emphasized. "Tonal Consistency" only exists when the notes are coming from the exact same (and unique) instrument, with the same exact harmonic signature, no matter which note, and no matter how loud that note is played. It's a "consistency" of dynamic emphasis and the unique harmonic structure of a particular musical instrument. Accordingly, it is highly difficult to accomplish, particularly for a speaker. Though, when it's accomplished, the speaker sounds disarmingly, and effortlessly, "natural".

Since this is a new category, I'm not absolutely certain what my "references" are, but I would say that, once again, the Ars Acoustica System Max is most likely the best I've heard in the past, with maybe the Original Apogee -if optimized- an "Honorable Mention". (Another good reason why the Ars was my personal speaker for more than a decade.) The Pure Reference appears to already match the Ars in this category, and is probably even superior, though that judgement will require a direct comparison. I write "superior" because I sense that the PR is even more revealing of the time/tonal distortions which are noticeable with (the numerous) records that are not exactly center pressed. I realize this isn't a purely objective (measurable) test, but when a component reveals more about a recording, for better or worse*, I believe that aspect of its performance is relevant.
Bottom Line- The Pure Reference is at least as good as any speaker I've heard in this critically important category, if not superior.

*Upon hearing the frequency modulation problems of LPs more clearly with the PR, I naturally became curious about why this was so. Eventually, the concept of "Tonal Consistency" came to me. It has always been there, just not as obvious.

Further- I will have more to write about this category, because of its vital importance to the reproduction of music. I'm still in the process of thinking my way through this subject.

Naturalness- In effect, I've already partially discussed this category within "Tonal Consistency". However, its musical importance, and its ubiquitous (and historical) presence within all serious audio evaluations, impels me to discuss it on its own. First the (or my) definition of "naturalness"; A combination of neutrality (linearity) and harmonic completeness. Either one of them, on their own, will not reach the final goal.
(Examples: If the sound is simply "neutral", missing some of the natural harmonics, the component will sound "analytical" and/or "lean". Alternatively, if you have only the harmonics, without the neutrality, you will get a "colored" sound, with an almost infinite choice of "colors". The former is true of many transistor designs, while the latter is true of many tube designs.)

My references will be no surprise; The Ars Acoustica System Max, Original Quad, Coincident Victory II and Total Victory II. The KLH-9 and Eminent Technology, discussed above, are also exceptional, but their amplifier requirements somewhat compromise the "harmonic completeness" part of the equation. This is a category where a lot of good speakers come close, but it's difficult to get an excellent score in both requirements. So what about the Pure Reference? Based on its "Tonal Consistency" performance, the answer is also predictable:

The Pure Reference is as natural* as any speaker I've ever heard, and maybe even more so. This is because it is natural in an unusually wide frequency range, 20 Hz to 30 KHz, and at both soft and loud volumes. This accomplishment is easily noticeable when you hear the PR, and may even be the first (disarming) attribute I heard during my initial audition with them.

*Example- Saudades-Water Lily WLA-CS-16

Inner Detail- Since I've already discussed "Outer Detail" above, it is obvious that I am making an important distinction between outer and inner detail. This is because there is no guarantee that accomplishing the former will automatically grant you the latter. Outer detail is mainly related to "speed", and, in particular, the ability of the component (in this case a speaker) to stop as quickly as the signal itself stops. The component's ability to "stop" the first note from extending on (artificially), allows the second (or subsequent) note(s) to be heard independently, and without interference. It should be no surprise then that speakers such as the Martin-Logan CLS or Audiostatic, both electrostatics with ultra-light diaphragms, enabling them to start and stop on a proverbial dime, excel in reproducing outer detail. However, inner detail requires another attribute. This is the (even rarer) ability to reproduce low-level information, because inner detail is, by nature, relatively soft in volume.

So while both the CLS and Audiostatic are still "very good" at reproducing inner detail, they are not "outstanding". What is? My long-time reference for inner detail is the Ars Acoustica System Max, which has the advantage of an ultra-low sound-floor, along with very good speed. To make a visual analogy, the Ars fills in "the coloring book" noticeably better than the fore mentioned speakers, though the "outlines" are not quite as precise. For another analogy, think of a piece of clothing, the outer boundaries (the edges) are the "outer detail", while the texture of the actual cloth is the "inner detail".

This brings us the Pure Reference. After break-in, I can state that its sound-floor is competitive with the Ars, while it has superior speed. Accordingly, the PR is my new "champion" when it comes to reproducing inner detail.

Transparency- This is an audio attribute that was initially observed by (Stereophile founder) J. Gordon Holt in the 1960's. Later, around 20 years ago now, Harry Pearson became almost obsessed with it (see TAS Issues 35/36). For some reason, it is not discussed as much today, being partially displaced by an assortment of worthless, "feel good" and highly ambiguous "magic words", such as "musicality" and "involving". This is too bad, because the existence of transparency, while much easier to accomplish now than in the past, is still highly important if the listener wants to fully appreciate the music.

I define transparency, in music reproduction, the same as I do in its most common visual context; being able to hear (or "see") into the performance. In the most simple and practical terms then, this means the listener is able to hear what's going on all the way to the far back of the recording studio (or the concert hall). Until 20 years ago or so, this was a rather unusual experience, and highly difficult to achieve, especially for speakers. However, superior drivers, components, crossovers and cabinets, plus better time alignment, has made this accomplishment much more common. In fact, the true test these days is not simply hearing "all the way back" (that's considered too easy now), but "what (how much) can you hear back there"?

So what are my speaker transparency "standards"? No surprise here, the Morrison and the Ars Acoustica once again. Now there are, without question, a pretty good number of other speakers (such as the Quad, Audiostatic and CLS) that will equal them in accomplishing "normal" transparency (defined above), but these two speakers give you an added "bonus"; they also allow you to hear the relatively subtle details of what's going on "back there". Of these two, I prefer the Ars overall, because while it is not quite as focused as the Morrison (nothing else I've heard is either), its ultra low sound-floor picks up more musical information and original space of the recording. As for the Pure Reference...

The PR is closer in performance to the Ars Acoustica, but more extreme. I would say the PR gives up a little on focus to the Ars, but, in return, it gives you even more musical information, plus it has the added advantage of greater accuracy of the music that is reproduced. So, while there is no clear-cut "Transparency Winner", I feel that the Pure Reference is not only competitive to the finest speakers I've heard in this category, but preferable overall.

Dynamic Response or Scale (Soft and Loud)- A few years ago, I wrote (in My Audio Philosophy) that "the weakest element in audio was the inability to reproduce lifelike dynamics". I feel this is still true today. Any casual brush with live music, long enough to experience its intensity, will provide overwhelming evidence in support of this statement. Of course, much of the overall loss is already within the software, but amplifiers and speakers share a lot of the blame as well. We're focusing on speakers here, but I feel I should reiterate one general observation with amplifiers; Rated RMS power has virtually no relationship with reproducing dynamic swings, though it does have a correlation with peak volume levels, which is very different.

Unanimity in audio is very rare, but there is an exception: Horn speakers are the most realistic reproducers of lifelike dynamics. This is particularly true in the midrange. In the frequency extremes, especially the bass, horns are generally no better than the competition. Conversely, electrostatics are usually the worst speakers in this category (especially in the bass), which is the main reason why they are avoided by many audiophiles. I'm not a horn expert, or enthusiast (outside of the Avantgarde Duo), but I have heard plenty of them over the years. My two standards for dynamics are the Duo (mids and highs only) and the (legendary) Klipschorn (full-range). There are probably a few more I've heard that match them, but I'm not certain enough to mention them.

Further, there are also a few outstanding dynamic speakers that basically equal my horn standards at very low to moderate levels, such as the Ars Acoustica System Max. What elevates these horn references is that they have minimal dynamic compression at all volume levels. This (relatively) effortless quality is the main reason why people can go "crazy" over good horns. They can induce a strong feeling of exhilaration with the right music, which is as difficult to forget, or ignore, as any other peak emotional experience. For some, it may even become "addicting".

My personal dynamic test is whether a speaker can "startle" or simply "surprise" me (even subtlety). To do so requires the ability to instantly change the volume, softer or louder, before the listener's mind is ready for it. It is here that large speakers (and most large amplifiers) fail, because of their complexity, which causes a form of "dynamic inertia". Yes, they can play "really loud", but this loud volume level is "telegraphed", and like pro boxing, it's the punch you don't see coming that has the greatest effect (in this instance, on the listener). So where does the Pure Reference fit into this difficult category?

With the exception of the finest horns in the midrange, the Pure Reference is as uncompressed as any speaker I've ever heard. Just as important, it is uncompressed full-range*, and in this instance, that means all the way down to 20 Hz. This separates the PR from almost all horns, which tend to lose some dynamic strength in the lower frequencies. Compared to the Ars Acoustica, it matches the Ars' outstanding performance at low to medium volume levels, but the PR extends this dynamic capability to very loud volume levels (fff), and at both frequency extremes.

In short, the Pure Reference is competitive (if not superior) in dynamic response, full-range, and at all volume levels, with any speaker I've heard, and that includes the finest horns.

*This is something I have never experienced before. You can call it "Dynamic Consistency". I feel this is more important than simply having the best dynamics in a frequency range, even the vital midrange.

Intermission- Break-In Update

The Pure Reference now has around 500 hours on it (June 2008), though less on the (sub)woofers. The improvements become subtle after around 300 hours, but are still noticeable: The sound-floor drops; the dynamic range expands and the tiny "resonances" become even less noticeable. I believe 500 hours basically finishes the process. Israel Blume, the designer, agrees with this assessment.

Sound-floor, "Completeness" and Low-level Information- Since the inception of this website, I've been emphasizing the critical importance of this performance category. This focus included detailed descriptions of how the performance in this area so critically effects the ultimate reproduction of music (see My Philosophy and Reference Components).

I would have discussed this category much earlier, but the sound-floor is usually one of the last performance areas where you will notice an improvement as the component is breaking-in, and this has proved to be the case here also. I've heard enough already, and with verification by a recently visiting associate, that I can state this now:

The Pure Reference has the lowest sound-floor of any speaker I have yet heard. It is even superior to my previous and long-time sound-floor "champion", the Ars Acoustica System Max, though not by a "dramatic" margin. The fact that it is even "noticeable" is significant enough for me. For those readers who would like a definition of "sound-floor" (which many audiophiles refer to as "noise-floor"), I will repeat what I wrote in Reference Components. The sound-floor is:

The "lower limit" of an audio component's capability to reproduce (or pass) softer and softer sounds.

Put in another manner, it can be described as:

The softest sound that can be heard or sensed through that component (or system).

(And that by definition means)

Any sound that is lower (or softer) than the "sound-floor" Must be Inaudible.

Analogy- It is the audio component's (or system's) direct equivalent of the listener's ability to sense or hear "soft sounds".

Now, what does all this mean in real-life listening to recorded music?

It's the low sound-floor of a component (and complete system of course) that allows you to hear the natural harmonics, body, decays, space, ambience and subtle dynamic shifts of the original recording. It also reduces the tendency for musical homogenization. Another benefit is that the component, in this case a speaker, doesn't change (by "dying") when the music becomes softer in volume. This weakness, so common in speakers, forces the listener to play extra (unnaturally) loud if he wants the music to always sound "alive". Listening at a natural volume even enhances the dynamic excitement of the music, because of the extra contrast when going from truly soft to truly loud. Playing "loud" and then "extra loud" is a poor and unsatisfying substitute for natural contrasts.

The Pure Reference, by virtue of its outstandingly low sound-floor, reproduces more low-level musical information than any speaker I've heard, while also allowing a natural volume level to be used, without any compromise of the recorded dynamic contrasts.

We've now reached the end. I've saved this for last because I feel it is the single most important category, and it's also the Pure Reference's "Trump Card". The Final Category...

Individuation!- As I've grown older and more experienced, it is my increasing conviction that a component's ability to Individualize each instrument (including voices), and the recording space, is its most difficult, musically rewarding and ultimate challenge. If the ultimate goal of listening to (recorded) music is a human-to-human, emotional, intellectual, spiritual and artistic "connection", I don't see how anything can be more important than individualizing each musician as a unique and distinct artist, along with their own "space". Further, by definition and simple logic, the unavoidable rule is that every weakness of a component (and system), either of omission or commission, will compromise that desired individuality. Some examples...

Every coloration masks some of the inherent sound (aesthetic) of, and adds an artificial quality to, a unique instrument. Every dynamic compression, no matter how subtle, diminishes some of the musician's original emotion. Every subtraction of the natural harmonics and decays makes the musician and space sound more "generic". Any loss of transparency removes at least part of the complete musical picture (performance). Accordingly, when a component lacks the capability of individuation, what the listener will experience is inevitable...

The musician(s) will lose (some of) their one-of-a-kind individuality which makes them "special". In effect, the musicians are "seen" (heard) in the same manner that a person of prejudice sees people of a certain (ethnic/racial/religious etc.) group; as basically all the same, and absent the individual characteristics which would identify them as unique human beings. Instead, they are seen as "generic" ("All the violins sound exactly the same to me!"), existing only in the limited, cookie-cutter version of that person's mind-world.

The inferior component, then, lacks the ability to adequately differentiate the instruments (or voices) that are similar. For another analogy: An ordinary person may not be able to distinguish a piece of pure, shining glass from a real diamond. However, a true jewelry expert (like an outstanding component) can look at a diamond, and not only confirm that it's real and give you its exact value, but can even tell you where it was mined.

The Pure Reference absolutely excels in the ability to individualize musicians* and their recording space. It is, without a doubt, the best I've heard in this all encompassing category. It is also the main reason why I feel it is the finest speaker I've ever heard. The finest I heard before the PR was the Ars Acoustica System Max, and I've heard numerous speakers since I purchased them more than 10 years ago, a rare few of them excellent in this category. The Pure Reference is both a qualitative and quantitative improvement over the Ars, reproducing a little more of the unique character of the musicians, and retaining more of that enhanced quality at higher volume levels and at the frequency extremes.

Every other speaker I've heard either compresses, colors, distorts, veils, rolls-off and/or subtracts more noticeably than both the Ars and PR. In fact, in most instances, the other speakers I've heard, even the finest, compromise the level of individuation in multiple ways, so the performance gap between them is pronounced. Most audiophiles, and especially mainstream "reviewers", don't dwell/focus on this serious problem. This is probably because most audiophiles have never had the experience of hearing a system where this problem is mainly "overcome" (in only the relative sense of that word of course, because this is audio).

Someday, inevitably, some speaker, of unknown origin, will further improve on the Pure Reference's unprecedented "Individuation" capability. Maybe this speaker already exists as this is written, but I know I haven't heard it myself.

*If the word "musician" is too personal to accept scientifically or technically, than replace that word with "notes". It's the concept of individuation that is important, not the focus on the object or subject.

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PART THREE- AMPLIFIER REQUIREMENTS

As I mentioned in the Introduction of this extended essay, the Pure Reference is "unusually flexible" when it comes to both amplifier and listening room requirements. If anything, I've come to believe that this was an understatement.

During the time I've heard the Pure Reference in my own system, it has been mainly bi-amped, using the Coincident Frankenstein amplifier on the midrange/tweeter, and the Coincident Dragon amplifier on the subwoofers. However, I've also heard the Frankenstein drive the PR full-range, but only on a digital source (MHZS CD66-Modified).

Previous to this, when I initially auditioned the Pure Reference in Toronto, I heard them full-range with the VAIC/KR VV52B amplifiers, for over 40 hours, both on a phono (VPI HR-X "Special Edition"/Dynavector XV-1S) and a digital source (Oracle 2500 MKII). These are the only amplifiers I've heard with the Pure Reference, and I've yet to hear the Dragon playing the PR full-range.

I've also had one other important and surprising observation. For some unknown reason, the Pure Reference plays louder (around 2dB) than the Total Victory II, or the Victory II, when everything is exactly the same (including the volume control's position), despite the fact the the PR is 3dB less efficient on paper.

Israel Blume, of Coincident, has also experienced this same phenomena in his own system, which I confirmed during my Toronto trip, but he still has no technical explanation for it. I thought, at the time, that this was some sort of fluke response confined to Blume's system, but the PR is also more efficient than the Victory II in my own system. Whatever the reason, this is good news, because it means that the (94dB) PR is even easier to drive than the (97dB) Victory series.

Based on all these experiences, I feel that the Pure Reference can be driven, full-range, by virtually any (SET) amplifier. The only possible exceptions are a true "flea power" (less power than a 300B or 50 output tube); like an amplifier using a 45 output tube. Amplifiers using 2A3 tubes should be viable, but they are probably right at the "tipping point", so a definitive answer will require an actual audition. Of course, I'm assuming that the listening room isn't "gigantic" and the loudness levels are "natural". As for transistor models, I can't think of even one of them that won't drive the PR, and with ease.

Now, to put things in clear perspective, I want to elaborate on "driven full-range". By this I mean that the amplifier(s) will have no problems with virtually any music, with the only exceptions being those (far less than 1% of) recordings that are simply ultra-demanding. These recordings will usually have both sustained (organ) and percussive bass playing simultaneously. Other than that, there shouldn't be any noticeable problems, and I can even provide a specific reason for this confidence, which I experienced myself in Toronto.

My Ultimate Test

Near the end of my multiple listening sessions, I made a request to hear a Mobile Fidelity LP (510): Holst's The Planets, and specifically the first movement on Side Two- "Saturn". This cut starts off very softly, then slowly becomes very loud and finally ends with ("killer") sustained organ notes. These particular organ notes have proven to be the "Achilles' Heal" of many otherwise excellent subwoofers, including the largest (and most powerful ever) Entec subwoofers. Years ago...

During the early 1990's, I had two pairs of the Entec SW-2s, which were stacked on top of cement blocks (an 8' tower!). This means there were two amplifiers, and 6 woofers per channel. Even this all-out combination couldn't handle those organ note(s). Not even close. The Entecs distorted to such a scary degree, that I thought they were going to be damaged. And now we were going to hear the Vaic VV52B SET driving the Pure Reference on the exact same cut. The results...

The Vaic handled the organ notes with no problems. It went deep, and with both power and control. I wouldn't say this was "the best" I've ever heard with this section, but it was still excellent. Needless to say, at no other time did I ever hear the Vaic amplifier have any problem with the Pure Reference, no matter what LP or CD was played, and many of them were very demanding. According to Blume, it takes the Reference Recording (RR-11) of Symphony Fantastique (Side 3/4), or a Japanese Kodo Drum CD, for the Vaic (or the Frankenstein) to demonstrate any type of stress.

In my own system, the results have been the same. While I don't have very many CDs in my collection, I do have a number of large orchestral and soundtrack (synthesizer) recordings, and the Frankenstein, full-range, has handled all of them with relative ease. It has even shaken my walls at times. So...

Considering that my room is pretty large (27L X 19W X 10H), and Blume's room is also good sized (at least in width), I feel it is fair to say that virtually any good SET amplifier should be more than sufficient for most audiophiles, in most rooms, including those listeners with diverse musical demands. For those audiophiles who require absolute assurance, and no possible compromises, then biamping, or using a push-pull amplifier full-range, will be necessary.

Finally, I feel it should be emphasized, because of its importance, that all of these amplifiers, including the transistor models, will usually be heard "at their best" with the PR. This is because of the ultra-easy load of the Pure Reference, and not just its high efficiency. This is an ideal situation where all that matters is the quality of the amplifier, because the quantity (in watts and/or current) is basically irrelevant.

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PART FOUR- LISTENING ROOM REQUIREMENTS

I've heard the Pure Reference in two rooms, my own in Florida, which is pretty large (see above), and in Toronto, where the room was around "average" in length, slightly below average in height, and far above average in width. The PR sounded outstanding in both rooms, though what particularly impressed me was the size and scale of the soundstage in the Toronto room, despite its relatively low ceiling height.

Over the years, I've been in countless rooms with low ceilings (less than 8 feet), usually in basements, but this was the first (and only) time I experienced a large and spacious soundstage in one of them. The sense of height amazed me, as though the ceiling had almost disappeared. Hearing side and back walls "disappear" is a routine occurrence with good systems, but not the ceiling in my experience.

When performing my normal setup in my own listening room, and also when I was in Toronto, I listened to the PRs at varying distances. I needed to know what happens up close and far away, and everything in between. This was mainly to optimize my own setup (which I will discuss in Part Five), but I also wanted to know if there was a problem someone else couldn't avoid, because they lacked my flexibility in speaker placement. Bottom Line- I couldn't find any distance that was "problematic", short of being literally on top of the speakers.

Based on these experiences, I would say that the Pure Reference will work well in virtually any room imaginable. The only exception would be something just too small, say less than around 150 sq. ft., where the subwoofers would most likely simply overpower the room. To hear the PR at "its best", would require, I believe, a room of around 300 sq. ft. or larger (20 X 15). Of course, "taste" has a place here, because some listeners enjoy a more intimate sonic presentation, which is easier to achieve in a relatively small room.

I must stress that when the Pure Reference isn't in "the ideal room", which few people actually have, its superior performance will not only still be evident, but it's likely that its sonic advantages will be even more noticeable. This is because most speakers are even more compromised when they're not totally optimized. This is exactly what I meant by the Pure Reference's "unusual flexibility": It suffers less compromise than any speaker I've heard when the listening room is not fully optimized, and I believe this rule also applies to amplifiers.

A Potential "Bonus"

Because the Pure Reference is able to retain its "sonic integrity" at lower-than-life volume levels, this means it may be played in both close proximities and/or at unusual times, that could otherwise cause problems with sensitive family members and/or intolerant neighbors.

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PART FIVE- OPTIMIZING MY SETUP

The most difficult part of positioning the Pure Reference is handling its 190 lb weight. Since the speakers in my listening room are on a thick carpet, I was able to slide them into the optimized position (and then later install the "Extender Feet").

I found the most critical aspect was the "toe-in", or how the PR is "aimed" at the listener. The last two speakers I owned, the Wilson WATT and the Ars Acoustica, were both aimed at my outer shoulders (as was the Victory II) for optimization. In other words, the tweeter, if it was the barrel of a rifle, would be aimed at the outer part of my shoulder; right tweeter to right shoulder etc. So, I naturally thought that after 3 successive optimizations, using the same formula, I had discovered some sort of set-up "rule". Well, I didn't.

To my surprise and annoyance, the Pure Reference was too "intense" or just too bright when it was positioned exactly where the Ars Acoustica was, including the same toe-in. Moving it back helped a little, but it was still "wrong". I could have contacted Coincident, but I consider that "cheating" as long as there are other options, and it can also create a form of lazy bias as well. So I tried something else;

I moved my head back and forth a foot or so, which mimicked the effect of changing the toe-in. Based on what I heard, I realized that my toe-in "Rule" was false, so I started changing the angle. I ended up with the "Inside" panel of the PR aimed at the outside of my shoulder*. The tonal balance of the speaker dramatically changed for the better, and so did the size of the soundstage. Everything now sounded "natural", and while the exact center listening position provided the best possible sound, which is always the case, sitting outside of the center still gave very satisfactory results. Satisfied, I called Israel Blume of Coincident, and discovered his speakers were angled-in exactly the same as mine!

*Stand behind the PR and align your eye with the inside of the cabinet. It should be aiming at the tip of your (friend's) outer shoulder, or a marker where your own shoulder would normally be.

Next, it was now a matter of positioning the PR the correct distance from the back wall, while always keeping the "aim" exactly the same.

I started off around 4.5' from the back wall (measured from the rear of the PR, which is 2' deep). I went back almost two feet, and then started moving the PR forward again. I was trying to optimize the "Image Size" (especially the depth of field and "layering"), while also retaining the PR's sense of "Immediacy"*, simultaneously. I found that around 3.5' from the back wall was the best choice (so the front of the PR is 5.5' into the room), but a few inches either way didn't make much of a difference. My room is around 27' deep, and in Toronto, where the room was 15' deep, the PR was 2' from the back wall.

*The deep bass is almost always the third parameter in the speaker positioning equation. Totally optimizing both deep bass and soundstage size and depth is virtually impossible, because the former normally requires close proximity to room boundaries (corners), while the latter requires just the opposite. In this instance, the PR's ultra-tight bass tuning ensured that the deep bass didn't change along with the position. Thus, this was not a factor during this process.

The next part was routine.

The Pure Reference has mirror-imaged subwoofers, so the speakers had to be switched to find the position where the room's standing waves were the least noticeable. In my case, I was very fortunate, both positions, woofers inside or outside, sounded virtually the same, so I kept the woofers to the outside. I did so because then they wouldn't face directly at the tube amplifiers. According to Blume, when both positions sound the same, which doesn't happen too often, that means the room has only very minor standing wave problems (to avoid).

Lastly, after everything is completed as described, the (supplied) Extender Feet are attached to the speakers (4 per cabinet). This is an absolute requirement* if the speakers are to be heard at their best. The PR is so much more cleaner and focused, and the bass is so much tighter and controlled, that I had to actually change the (low pass) frequency of my subwoofer crossover after they were installed.

Very Important- You must not install the Extender Feet until the very end, because the speakers can no longer be moved after they're installed, without actually lifting (or "walking") them. I've "walked" them on my own, but even then you're risking serious back problems if you are momentarily careless with their 190 lb weight. Also, unless you are in really good shape, installing the Extender Feet is a two-person job, because the speakers must be first placed on the floor (gently), and then lifted back up and placed back into the correct position.

*The Extender Feet also greatly reduce the chance of the PR ever being tipped over, which could obviously have catastrophic consequences.

Final Option - Changing the Incline

I've used speakers with front inclines (the Wilson Watts and Ars Acoustica) for the last 20 years, 1988-2007. During that time, I have received excellent results with them (especially in Image Focus), so I decided to experiment with the Pure Reference as well. I first tipped the speakers back, but raising the front two Extender Feet. That gave me almost an inch, and then I later used a metapolymer plate, 1" thick, underneath those same two front feet, giving me 2" total. I heard positive results, better focus and driver integration. In general, the closer the speakers are to the listener, the more noticeable the improvement. Just be careful to retain the speaker's stability during this process.

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PART SIX- SONIC COMPARISONS

The Closest Competitors

I've already made dozens of sonic comparisons above, but they were all focused on individual performance categories. Now it's time to compare the "overall" performance of the Pure Reference with its closest competitors. Unfortunately, as soon as the "overall" perspective comes into play, virtually every speaker I've ever heard is immediately eliminated from contention, because whatever strengths they possess, their weakness are simply too noticeable to qualify. (An Analogy- This is also why so few athletes can seriously compete in the Olympic Decathlon, no matter how talented they are otherwise.)

Of all the speakers I've heard, "at their best", and with no qualifiers, I would have to say that the Ars Acoustica System Max and the Coincident Total Victory II (TVII)* (both discontinued) are the closest overall performers to the Pure Reference. Other speakers will be discussed also, but they will have various qualifiers and caveats, some of them very serious. (*Or the Coincident Victory II with a proper subwoofer.)

PR VS. ARS- The PR is very similar to the Ars in basic design philosophy. Both are essentially two-ways (like a Mini-Monitor) with their own subwoofer. The Ars, like the earlier designed Wilson WATT/Puppy, has separate cabinets for the satellite and the subs, while the PR is an all in one box, though it has separate internal enclosures to avoid sonic interference. The Ars uses dense polymers, which are even stronger than those used in the WATT, while the PR uses about as heavy a MDF cabinet as is theoretically possible, which is why it is 190 lbs. I give a slight advantage to the Ars in the cabinet(s) department, because, ultimately, it feels even "deader" than the PR. However, everything else is in the PR's favor, the drivers in particular, and the sonic results demonstrate this superiority.

Fundamentally, the Pure Reference is an enhanced version of the Ars; being more extended, cleaner, faster, more cohesive in the mids/highs, more dynamic, more immediate and transparent, with greater volume capability and even easier to drive (especially full-range with one amplifier). They're both very neutral and have an ultra-low sound-floor, which makes them very similar in their "basic sound" or (lack of) character. If the Ars has any sonic advantage, I would have to say it is still slightly better in image focus, but I haven't totally dialed in the PR yet, so that may change.

PR VS. TVII- I find the comparison of the PR to the TVII to be even more interesting. They share no drivers in common, though the cabinets are quite similar, with the PR being a little larger. The PR has 4 drivers per channel, while the TVII uses 9, and that epitomizes the differences between them. The TVII is slightly more extended on the top, while the PR is slightly more extended at the bottom, but the PR's advantage here is more noticeable (and important). However, the serious differences between them are:

1. The PR has only two drivers between 150 Hz and 20K, while the TVII uses 5 and, just as important...
2. The PR's two drivers are as similar in design and material as is currently possible, while the TVII's drivers consist of 3 very different types.

Basically, most of the differences between the PR and TVII are relatively minor (and much less noticeable than the ARS), especially when it comes to speed and purity etc. They are uncannily similar at times. However, the PR not only improves on the TVII's "weak suit" of multiple midrange sources, as does the ARS or any excellent two-way, but it goes further, much further. The Pure Reference's superior (and unprecedented) midrange/tweeter "transition" and uniform (lack of) character are the closest to a true (and ideal) one-way that I've ever heard. So, the PR not only has a large superiority over the (inherently disadvantaged 3-way) TVII, it also has a noticeable superiority over the best 2-ways as well. This, alone, makes the PR truly "special".

In short, even if you combined the best qualities of the Ars and TVII into one "super" speaker, which is how one could superficially describe the PR, the Pure Reference would still be noticeably superior to that theoretical speaker. So the performance gap between the PR, and these two (otherwise outstanding) speakers, is actually large enough to allow other speakers to fit in between them.

Two "Ceramic" Competitors

There are now quite a number of speakers that use the ceramic drivers from Accuton. A number of them will be discussed in the "Price Comparisons" section just below. I was also able to actually hear some of these models when I was at the 2004 CES in Las Vegas. I, and an associate who was with me during the show, still have some relevant memories of at least two of them; the Kharma Midi-Grand Ceramique and the Lumenwhite Whitelight. (I also made notes of our impressions at the time, which I subsequently posted in my "Show Report".)

We were impressed with both speakers, considering show conditions, though the Lumenwhite only performed really well on the last day of the show. At the time, neither of us knew very much about ceramic drivers, though they obviously looked a little different than those using the standard paper and other materials. The main difference appeared to be the prices for these speakers, which were among the most expensive we had ever seen for their respective size and driver complement.

The Kharma had some good qualities, see below for details, but lacked both deep bass and dynamic impact, despite the fact that it was driven by very powerful, and expensive, Tenor Hybrid mono amplifiers. The Pure Reference, even with the relatively low powered SET Frankenstein amp, sounds like a dynamic powerhouse by comparison. The Lumenwhite (room) was better than the Kharma overall, but then it did have a serious analog front end and probably better (tube and SET) electronics. It also didn't go real low or have intense dynamic capabilities, and this time they had no excuse in either the source or the amplification. So while I liked much of what I heard, I didn't feel they fully competed with my system at the time (Ars Acoustica/Golden Tube 300B), let alone the even noticeably superior Pure Reference and Frankenstein amplifier combination.

The "Qualified" and the "Theoretical"

Now, what about other speakers, those with outstanding qualities, but also with the "caveats" and "qualifiers". These will now be discussed, and it must be emphasized that, at this point, cost is not a qualifier. We will be focusing on performance (even when it's purely speculative), and it will be broad enough to even include speakers that are "theoretical" (meaning that I'm not sure they even exist!).

First, when using the qualified with the least amount of speculation and risk, I would say of all the speakers I've yet heard, the closest sonic competitor to the PR would have to be the Avantgarde Duo with Basshorns (BH). Assuming you had the proper room, I would choose them as an "alternative" to the Pure Reference. The "qualifier" here is that I haven't heard the BH myself, but I feel enough veteran and highly critical audiophiles (including some readers) have been impressed enough with them that I would take the sonic leap of faith.

The Duo has a slight advantage in dynamic force (its greatest strength), and maybe even purity. (For many, this unique horn projection will alone prove decisive.) Both speakers are very immediate. However, I (would) still prefer the PR overall, because I feel it is more neutral, disappears better, goes lower in the bass and is even more cohesive. Further, the fact that the BH has its own built-in transistor amplifier is also a downside for me. I strongly believe that tube amplification is a requirement at this (highest) level of music reproduction.

The Duo's advantage in sensitivity is real, but it's irrelevant in most cases, because the PR is highly sensitive itself, already plays much louder than I (and most audiophiles) require, and there's no ultra-low power amplifier, that I currently know of, which is superior to the finest (300B based) amplifiers I've heard.

The PR has another important practical advantage over the Duo, and that is in Listening Room Flexibility. I have a truly large room. At most, only 2% of the listening rooms I've seen are as large (or larger). Still, I am unable to use the Duo/BH combination, unless I want to go through windows to access my bedrooms, den and bathrooms. My former listening room in Toronto, similar in size to my Florida room, would have been ideal with the Duo/BH. What's the difference? The Toronto room was totally dedicated to audio, and had corners without entrances. In practical terms then, to hear the Duo/BH at "its best", will require a room that maybe only 1 out of 100 audiophiles have available to them.

Next come the "theoretical" speakers. First up is another horn "design", which is really an all-out DIY project. It is only for the most serious, patient and experienced audiophiles. I'm referring here to the horn projects discussed at Romy "The Cat's" website (www.goodsoundclub.com.). These DIY projects include dedicated, custom built amplifiers for each frequency range. This is as "avantgarde" and extreme as you can take audio. I would get involved myself if I was younger (and richer) and had more space. This is only for people who really love and appreciate what horn speakers can uniquely do, and are prepared to optimize them at any cost; in time and money.

Finally, there is the "dream speaker" I've mentioned in the past, but have never seen (even in pictures), let alone actually heard. Maybe it's just a rumor, but I want to be as complete as possible in this essay, so it must be mentioned. I'm referring to the new Apogee, "built" in Australia, and based on the Original Apogee (the 1980's speaker with so much potential, and yet so frustrating, because of its almost impossible load). However, this new company has claimed that they have totally solved the loading problem. In fact, they even claim their new version has 100 dB sensitivity! This is obviously the most extreme change imaginable; going from being almost impossible to drive, to even a SET amplifier being able to drive it! Is it real?

I don't know. If anything, "it sounds too good to be true", but if it is, and everything else about the new version is the same (or better) than the Original Apogee, than I can't think of another speaker that could equal its performance, including the PR. It would possess, in theory, a combination of speed, purity, cohesiveness, neutrality, impact, immediacy, dynamic range, extension, image size and completeness that would be unprecedented. Unfortunately, this ("Super") Apogee is supposed to cost $ 100,000 a pair, but even then, for the first time in my life, I would finally agree that a component costing that much was actually worth it. For now though, the Pure Reference is the closest equivalent I know to this theoretical "super speaker", including the easy drive capability.

So that's every relevant comparison I can think of, even in my imagination, literally. There are, of course, many other speakers I could have brought up which are excellent performers. Some of them are mentioned above (Quad, CLS, MBL, Morrison, Sound Labs etc.), but their sonic problems are even more noticeable than those I chose to discuss, so it would be only an academic exercise.

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PART SEVEN- PRICE COMPARISONS

I almost always make some form of relevant price comparisons, especially if any of the closest competitors are either considerably less, or more, expensive. In this instance, I'm going to be far more encompassing, because this is the only the second time, in the history of this website, that I've made a reference of any (currently available) component which has a "list price" of $ 20,000 (or more).

This obviously raises the issue of "value" to the discussion, which always has at least some elements of "relativity" and personal impression to it. However, for the perspective of this essay, I'm removing (and ignoring) the subjective element of "value" (which is impossible to calculate and much too easy to abuse). Here, we are only going to focus on the ratio of the best estimated manufacturing cost to the actual retail price. This is a purely objective approach to "value", which is almost always avoided by mainstream audio reviewers, despite its critic relevance to their readers and potential purchasers.

I'm going to break the comparisons down into two separate groups. The first group consists of four speakers, three from a single manufacturer, all using midrange drivers that are very similar to that used in the Pure Reference, though they're not exactly the same. These critical drivers all come from the same manufacturer (Accuton).

The second group, consisting of three speakers, doesn't use any drivers that are similar to those in the Pure Reference. These speakers are still included because they're either "famous", or (currently) "Hot", and are generally well-known and "respected" by many serious audiophiles. All of these speakers are still available new as this is written, and they have also been recently reviewed by one, or more, magazines of the mainstream audio press. (Predictably, all the "reviews" were "raves".)

Before we begin, let's refresh ourselves as to what drivers are used in the Pure Reference. The PR uses two (very expensive) ceramic drivers from Accuton; a 6.5" midrange and a 1.2" dome tweeter. Neither one of them is "stock". The major, and most important, differences are that these "custom" drivers are much more sensitive (94 dB) and also have a "totally flat" impedance. There are also two very expensive, and heavy duty, 12" woofers, which I've held in my own hands. Each woofer costs almost as much as the ceramic midrange. The cabinet is also extremely well-made and braced (190 lbs). The internal wiring, and crossover parts, are all as good as it gets. (I would go the Coincident website for the actual details and verification of this brief, paraphrased summary.) The Pure Reference's "List Price" is $ 22,000 (a pair).

The First Group of Price Competitors

Since the primary sonic contribution of the PR comes from the Accuton ceramic midrange driver, I chose the Kharma speaker company to mainly represent the first group of 4 speakers, since they use a very similar driver in a number of varying designs. Here are the details:

Kharma Ceramique 3.2
Two Way using Focal Titanium Tweeter and Accuton ceramic 6.5" mid/woofer.
Price : $21,000
70 lbs.

Comparison- This speaker is the closest in price to the Pure Reference. It also has a very similar version of the Accuton midrange driver. Other than that, they could hardly be more different. The 3.2 uses a Focal tweeter, while the PR uses the matching Accuton tweeter, which is far more expensive. Most importantly, the 3.2 uses its Accuton driver as both its midrange and its "woofer", while the PR's has two separate 12" woofers. Finally, the Ceramique cabinet is much smaller and, at 70 lbs, is 120 lbs lighter.

Here's the relevant part of what TAS (Harley/Valin) wrote about the 3.2: "Best Sound at Home Entertainment 2002 Show" (Issue 137, Aug/Sept 2002, Pages 33-34)

"...First place, however, goes to the Kharma Ceramique 3.2... This... stereo system had the most realistic sound of any at the show. Dynamic, detailed, superbly transparent, incomparably rich in color, gorgeous in the treble and midband... its only weakness... was a slight roll in the very deep bass (sub-40Hz), which, nevertheless, didn't keep the Kharmas from roaring like an orchestra in full voice on the last movement of the Rachmaninoff Third Piano Concerto..."

Personal Notes- I wasn't there, but I know, with a certainty which can only come from the laws of physics, that one observation by TAS is total nonsense; "its only weakness...was a slight roll in the very deep bass...". Reality- The single 6.5" Accuton driver has basically no "deep bass". In fact, it "drops like a stone" below 70 Hz, its resonance point, which means that even the 3.2's mid-bass is severely rolled-off. Actual frequency measurements confirm this, and nothing TAS says can change that fact. (So, we've now actually reached the pathetic point where the mainstream reviewers can't even concede that a 6.5" driver has serious problems when it's futilely attempting to accurately reproduce deep bass.)

The Focal tweeter, while quite good if it's modified (such as in the Ars Acoustica System Max), has a number of its own problems. Then there's the transition between the two drivers. They can never be as seamless as the PR, where both drivers are made by the same manufacturer, using the same materials, and specifically designed to work as a matched pair.

Bottom Line- If someone is truly impressed with the Ceramique 3.2, think of how they will react to a speaker, at almost the same price, with:
1. The matching ceramic tweeter to go with the midrange,
2. Two very high quality 12" woofers, that extend the bass down to a real 20 Hz (and which also relieve the midrange driver from the bass modulations)
3. 120 lbs greater total mass
4. A load so benign that it can be even driven with low power SET amplifiers

Kharma Grand Ceramique Midi 1.0
Three way using Accuton ceramic midrange, Focal titanium tweeter and one 11" woofer.
Price: $40,800
170 lbs.

Comparison- This speaker is much closer in design to the Pure Reference. While it has the exact same Accuton midrange and Focal tweeter used by the 3.2, there is one major difference between them. The Midi also has a real woofer this time, which should extend the bass into the last octave. The Midi's weight is also pretty close to the PR, being only around 20 lbs lighter. (Since the approximate weight of the PR's extra woofer is also around 20 lbs, this is a non-issue.) It was reviewed a few years ago by Michael Fremer (still available on the Stereophile website for free). Needless to say, it was another "rave".

I heard this speaker a few years back, with Tenor (hybrid) amplifiers in a good sized room, and the sound was impressive (for "audio show sound"). It was relatively natural, clean, fast and there was a large, focused soundstage. The most noticeable problem was the severe roll-off in the deep bass, in spite of the 11" woofer, tremendous available power and a much larger cabinet. (This is more direct evidence why the TAS write-up on the Ceramique 3.2 is total rubbish. If the Midi can't reproduce truly low bass, how can their model without the 11" woofer do so?) The Midi has relatively high sensitivity, but the impedance varies and it's even low at times. This makes it an easier than average load overall, but it's still not suitable for any SET amplifiers.

So what do you get for the Midi's extra $ 18,800 cost (the price difference between the Midi and the PR)? You get one less woofer, an inferior tweeter, a more difficult load, which means you will lose the option of using a SET amplifier, and a highly noticeable roll-off in the deep bass. The Midi does have a more beautiful looking cabinet though. I found it stunning myself.

Bottom Line- The Midi is almost twice the price of the Pure Reference. I wouldn't be able to explain how any serious audiophile could ever prefer it to the PR, unless what he sees is even more important than what he hears, which actually isn't that unusual these days.

Kharma Grand Ceramique 1.0
Three way using Accuton ceramic midrange, Focal titanium tweeter and two 11" woofers.
Price: $56,500
240 lbs

Comparison- This is the Kharma speaker which is the most similar to the Pure Reference in design. In fact, they're almost design clones of each other. The ceramic midrange and Focal tweeter are exactly the same as those used in the Midi (and 3.2) above. The only serious differences between this and the Midi is now there are two woofers (just like the PR), and of course the cabinet is a little larger. In fact, this speaker weighs even (50 lbs) more than the Pure Reference. The sensitivity and load are almost exactly the same as the Midi. Once again though, the cabinet is beautifully finished. As for reviews...

Positive Feedback (David Robinson) gave it a rave review (Issue 13- available on-line), plus it received a "Brutus Award". Robinson wasn't shy about his complete admiration for this speaker: "This was simply the very finest sound that I've ever heard in 15 years in my listening room. No exceptions...Of no other loudspeaker have I ever been able to offer such unqualified praise in all my years of reviewing."

One can only imagine Robinson's reaction to a similar speaker with an even better tweeter, made from the same material as the midrange (and with greater extension). Then add even better woofers, with deeper extension in the bass (the two frequency extreme rolloffs were the only faults Robinson could find). Then there's the PR's greater sensitivity and easier load on the amplifier. And all of this for 60% less than the price of the Grand Ceramique.

Bottom Line- Outside of slightly deeper bass and greater power handling capability, this speaker is an exact duplicate of the Midi. However, there is now a $ 34,500 price difference between it and the Pure Reference. So, what do you get for this extra investment? Inferior drivers and a more difficult load, with the offset of a heavier and more impressive looking cabinet.

Further- Is there a speaker which is even closer in design to the Pure Reference than the above Kharmas? Yes actually, the Avalon Acoustics Isis, which has almost the same midrange driver, along with somewhat similar (Eton) woofers, but it uses the (ultra expensive) Accuton diamond tweeter. The Isis costs $ 62,000 (almost 3 times the price of the PR). Still, I feel the Isis is a much better (relative) value than the Grand Ceramique 1.0 above. (Probably due to the Kharma line being imported from Europe.)

The Isis costs exactly $ 40,000 more than the PR. For this you get the diamond tweeter and a more attractive and slightly heavier cabinet. However, you lose a little low frequency extension. Most importantly, you also lose the ability to drive the speaker with a SET amplifier, since the Isis has a considerably more difficult load than the PR (or even any of the above Kharmas). For those familiar with the unique performance capabilities of the finest SET amplifiers, this constitutes a major disadvantage.

The Second Group of Price Competitors

The second group of three speakers come from three different manufacturers. Two of them should be well-known to everyone. The other one is a relative newcomer, but all of them have recently received a lot of hype in the mainstream audio press (Stereophile & TAS). First up is, by far, the most famous and established of them all:

Wilson WATT/Puppy 8 (WP8)
Three way using Focal tweeter, 7" Dynaudio midrange and two 8" Dynaudio woofers
Price: $27,900
170 lbs

I owned an earlier version of this speaker (WATT only), and heavily modified it. It was my "Reference" for almost 10 years (see "My References" above). However, I used various subwoofers with the WATT. (The Puppy, which has a severe roll-off below 40 Hz, has never been even remotely close to being a true subwoofer.) The WP combination has received countless raves over the years. Check out the June 2007, Stereophile (Wes Phillips) review, which is on their website. It's a rave of course: "While acknowledging that it's not perfect*...it captures the excitement of live music as do few loudspeakers I've heard."

*Phillips also reviewed the WP5 in November 1995, again gratuitously using the word "perfect". He also refused to mention even one specific criticism of the WP5. (See Reviewing the Reviewers for the details.) In the WP8 review, he finally describes all the problems he heard with the WP5 back in 1995. Maybe Phillips feels this will now change the historical record, but it won't. Phillips was apparently too terrified to mention these criticisms when they actually mattered, to both his trusting readers and to Wilson Audio. Instead, until now, they only existed in his fantasy world, where he is still the fearless audio critic and communicator. If Phillips is betting that no one would remember his past, he lost.

So, how does the WP8 compare to the Pure Reference in the price/value category?

Comparison- I would give the WATT/Puppy 8 a slight edge over the PR when it comes to the cabinets. While they are considerably smaller, somewhat lighter, and far less complex internally, I still feel they have an advantage because of the very expensive meta polymers being used. (The WP8 cabinets are still not as dead as the Ars Acoustica System Max, which are entirely molded.) Other than the cabinets though, there is no comparison between the two speakers.

The WATT uses the Focal tweeter (which they modify), also used by the Kharma speakers above. It can be excellent, but it's far less expensive than the Accuton ceramic tweeter in the PR. The WATT's Dynaudio midrange, while also of good quality and relatively expensive, is still a fraction of the cost of the Accuton ceramic midrange. Ditto the Puppy's two Dynaudio 8" woofers. They're good for sure, and not cheap, but they cost only a fraction of the price of the heavy-duty 12" woofers used in the PR. Further, the internal wiring and the crossover parts used in the Pure Reference also appear to be higher quality and more expensive.

Bottom Line- The WATT/Puppy 8 costs $ 5,900 more than the Pure Reference. What do you get for this extra money? You get a somewhat more expensive (and shiny) cabinet, but you also get four dynamic drivers, internal wiring and crossover parts that, in total, cost far less than those used inside the PR.

Finally, despite the ridiculous suggestion by Phillips that a 2 watt amplifier can actually drive the WP8, the truth is exactly the opposite. It takes considerable power and current to adequately drive the WP8 (or the earlier versions). This is because the impedance looks like a mountain range, and even goes down "to 2.2 ohms at 77 Hz". This is another serious disadvantage for the WP8.

Magico Mini MK II (with stand)
Two way using Scanspeak Ring Radiator ("Revelator") tweeter and 7" titanium composite mid/woofer.
Price: $29,900
80 lbs
(Stand 120 lbs)

This is the speaker that TAS (Jonathan Valin in particular) is really "pushing" these days (I used that word deliberately). In fact, I've never seen TAS, in their entire 35 year history, gush over any components like the Magico Mini line. (I wonder what Harry Pearson's reaction could be to this development.) The original review came out in November 2006 (Issue 163), and there's since been another review on the MK. II (Issue 179). The price of the Magico Mini has gone from $ 22,000 up to almost $ 30,000, which includes the matching stands. So it now costs $ 2,000 more than the Wilson WATT/Puppy 8, and $ 7,900 more than the Pure Reference.

Here's what Valin recently wrote about the MK II version of the Magico Mini: "If someone...had told me that the Mini’s fabulous midrange could be improved upon to this extent, I wouldn’t have believed him. But hearing is believing. Is the Mini II a 'perfect' speaker. Of course not..." Is it me, or do these reviewers appear to really like to bring up the word (and the concept of) "perfect"? As far as I'm concerned, shamelessly using a word like "perfect", as a tease, with loudspeakers no less, is an insult to the intelligence of audiophiles.

So, how does the Magico Mini MKII compare to the Pure Reference in the price/value category? Let's start with their cabinets.

Comparison- The Magico's cabinet is superbly made, but most of the total weight is in the stand (120 lbs), and not the actual speaker (80 lbs). While it does cost more to "shape" (and finish) the Mini, the Pure Reference is much larger and much more complicated internally. In short, the Pure Reference appears to have a decided advantage in cabinet value. Both speakers also use internal cables and crossover parts of the highest quality, so they are comparable here. However, the most serious differences between them are in their respective dynamic drivers.

The Magico's tweeter, the Scanspeak Revelator, is an excellent performer, used in many speakers (including some Coincident Eclipse models). It costs more than the popular Focal mentioned above, but it's still a fraction of the price of the ceramic tweeter in the PR. The Magico's midrange is an unusual design, rare and expensive, but it's still much less costly than the Accuton ceramic midrange used in the PR. The Mini has no dedicated woofers, compared to the two (highly expensive) 12" woofers in the PR.

Bottom Line- The Magico Mini costs $ 7,900 more than the Pure Reference. For this you get a cabinet of somewhat lesser value, though more nicely shaped and finished, plus internal parts which are comparable. After this, there is absolutely no comparison. The Magico's tweeter and midrange are of high quality, but still a fraction of the cost of those in the PR. Much worse, you also lose both of the high quality woofers included in the PR. In fact, the Magico is severely rolled-off in the bass. Ironically, the Magico doesn't appear to even equal the "cost value" of the WP8, which has been criticized itself for not being a good value.

Finally, but still highly important for many, the Magico Mini is a very difficult load, so it can not be used by any SET amplifiers. In fact, Valin himself recommended amplifiers of at least 200 watts per channel.

Peak Consult El Diablo
Three way using 1" Scan-Speak Tweeter, 5" AT Midrange, Two 9" AT Woofers
Price: $75,000
188 lbs

This speaker comes from Denmark. It was reviewed in Stereophile (May 2007), by Michael Fremer*. The Diablo, and its sister, the Empress, both made "Class A". The Empress was even the "Joint 2005 Loudspeaker of the Year". Fremer wrote: "I spent three months with the Diablos and found them to be among the most capable and musically engaging speakers I've yet auditioned...the Diablo is very expensive at $65,000/pair*. Although its value will be in the eye, ear, and wallet of the beholder...". Fremer also avoided making a direct comparison, or stating a clear preference, between the Diablos and his personal Wilson MAXX 2 speakers.

*The Diablo was distributed by Signals SuperFi at the time of the review. This is the same company that imports the Continuum turntable. They sold a Continuum to Fremer at "parts cost" (a discount of 80 to 90% off the retail price). Signals SuperFi later stopped importing the Peak Consult line, and Stereophile immediately removed the Class A recommendations. The Diablo's price, since the review, was later raised from $ 65,000 to $ 75,000.

Comparison- The price value comparison of the Diablo to the Pure Reference is similar to what we have already seen before. The respective cabinets are very competitive, in complexity, total size and weight, though the Diablo has a more polished finish. Peak also claims that the crossover parts have "been chosen for its sonic and musical behaviour, with no consideration for cost". They don't mention any specific brand names, but we'll give Peak Consult the benefit of the doubt, and call this a "draw". This brings us back, once again, to the speaker drivers...

Both speakers have 4 drivers, each doing the same exact task (2 woofers, a midrange and a tweeter), but that's were the similarity ends. The Diablo's Scan-Speak tweeter is well-known for it performance, and it costs more than the Focal, but, to repeat myself, it's only a fraction of the cost of the Accuton ceramic tweeter. The Audiotechnology midrange and woofers have the same story. These are, by reputation, high quality and relatively expensive drivers, but they cost far less than the Accuton ceramic midrange and the heavy-duty 12" woofers inside the PR. This matters even in the objective measurements, because both of the Diablos's frequency extremes are rolled-off by comparison with the PR. Finally, the Diablo's load is around average, so SET amplifiers are not usable with it.

Bottom Line- The Diablo costs $ 53,000 more than the Pure Reference. This is more than 3 times the price of the PR, and while its (more attractive) cabinet and crossover parts are comparable, the Diablo's speaker drivers, though undeniably of high quality, cost far less than those used in the PR. The Diablo, in direct contrast to the PR, also can't be used with SET amplifiers. Sadly, the Diablo may be the single worst speaker in this "value" survey, in spite of Fremer's blindness to that obvious reality. Even if you totally ignore the Pure Reference comparison, the Diablo actually costs $ 13,000 more than the Avalon Acoustics Isis, which also has far more expensive drivers.

Less Expensive Competitors

I will start off with the most relevant statement first ("The Bottom Line"): I don't know of another speaker which has the combination of such highly expensive drivers, high quality cabinet structure and all-out internal parts, that costs less than the Pure Reference. (I also don't know of a speaker that equals its performance for less money either, though that is a separate issue.) That said, there is, of course, more to the issue of "value" than just the selling price/manufacturing cost ratio, as important as I feel that is.

While I don't know of any speaker selling for less (or even more) than the Pure Reference that equals its overall performance, this certainly doesn't mean that it will be a typical audiophile's first choice when it comes to "performance for the money". There are numerous speakers, many mentioned above, that equal (or slightly exceed) it in different performance parameters. Even though the Pure Reference will exceed all of these speakers in overall performance (in many instances by a large margin), and further assuming this "margin" will be heard and appreciated by the listener, this still does not mean that the extra cost of the Pure Reference will appear justifiable to them.

This is because the speakers I've already compared the PR with in performance above, plus others, such as from Magnepan, Vandersteen, Legacy, Gallo and VMPS, as well as some DIY projects, have been able to satisfy countless audiophiles over the years, despite their more noticeable sonic faults. Further, these speakers are also known to provide "cost value" along with their "sonic value". It's obvious that only listeners themselves can decide whether the superior performance of the Pure Reference is worth the extra investment.

The critical perspective I'm trying to convey here is simple: Yes, the Pure Reference is an expensive speaker. However, it not only provides noticeably superior performance to any less expensive speaker (I've heard), it is also an outstanding value, considering its manufacturing costs. This is true when the PR is compared to not only more expensive speakers, but, much more importantly, even when it's compared to less expensive speakers. This achievement of "universal cost value" is very rare today, mainly because of recent audio marketing trends, but the Pure Reference is that rare exception to this unfortunate trend.

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CONCLUSION

This essay has taken me four months to write. This was necessary because I had three goals:
1. To help readers understand exactly why I finally changed my personal speaker reference after more than 10 years;
2. To also provide a basic "template" on how I evaluate the finest speakers, which I hope may be useful to others;
3. To clearly disclose my personal perspective on what I feel are the most important elements of music reproduction, and with practical examples.

This third goal required discussing my personal speaker history in depth. Ironically, it took this examination of my own past to discover, for myself, what was really most important to me. What I had only conjectured in the past, was finally confirmed when I saw it all for myself, in black and white. So, between this observation, and all the subsequent challenges required in the multiple sonic comparisons I made, this essay ended up being an exercise of "self-discovery", something I would never have predicted when it was started.

And, after all that has been written above about the Pure Reference's sonic performance, I feel it is possible, and necessary, to condense the entirety of it into two simple sentences, which are both personal observations and opinions:

1. The Pure Reference does more things "right" than any other speaker I've heard (it's the most "complete" or "natural").
2. The Pure Reference does less things "wrong" than any other speaker I've heard (it's the most "accurate").

It is critical to keep in mind that achieving Observation #1 does not mean achieving Observation #2 is a given. In fact, it can be just the opposite, because optimizing (either) one of them may require a "trade-off", thus compromising the other. Achieving both of them, simultaneously, is a rare and difficult accomplishment, but the Pure Reference has done it. This makes it not only a benchmark for audiophiles and/or music lovers, but also a potential "tool" for audio engineers.

Even from the perspective of the purely "practical", the Pure Reference has a number of important advantages:
1. It can be optimally used with virtually any existing amplifier, including the finest SET models.
2. It can be optimally used in virtually any listening room.
3. Its total parts costs (drivers, cabinet, crossover) are only matched by competitors selling for more than twice its selling price.

Because of both its unprecedented performance, and its unusual "practicality", I purchased a pair of Pure References for my own use. Unlike many audiophiles, particularly mainstream "reviewers", I rarely change components, especially speakers. It now takes something extraordinary for me to replace what I have. Something that I can't live without after hearing it. The Pure Reference is that "Extraordinary Something".

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FURTHER REFLECTIONS A YEAR LATER (06/2009)

I've now lived with the Pure Reference for more than a year and, with the exception of a few minor edits, I have not made any changes or additions to my lengthy review (above) of this speaker. I've decided it's time to do so because there have been both a technical change in the way the speakers are used in my system and I also believe I have some important and edifying personal observations to share.

On the technical side, in the last year I have changed my speaker cables, 300B output tubes and the Jadis JP-80's volume controls. In each instance there was a noticeable improvement in the system's performance. However, the most important sonic improvement came when I began playing the Pure Reference full-range with the Coincident Frankenstein 300B amplifiers. In short, I removed both the Behringer Digital Crossover and the Coincident Dragon 211PP amplifiers from my system (along with all their associated cables).

I made this change with a considerable amount of trepidation, because not only would I lose 90% of the available power for the subwoofers, I would also now have to rely completely on my preamplifier's bass level and extension, which hadn't proved sufficient since it was gutted from six tubes to two tubes back in 1993 (consistent with my "minimalist audio philosophy"). Fortunately, my fears proved, so far, to be groundless...

As I wrote in August 2008, to my surprise, I've received outstanding results with the Frankenstein playing the Pure Reference full-range. Not only is the sound more cohesive, there is also more bass detail, a larger image, better focus and a lower sound-floor (with all the associated benefits). The overall improvement is such that I can't go back to biamping (using an electronic crossover). I'm even going to experiment with different turntable settings and cables because of the more revealing nature of the system.

Now I did help matters somewhat by increasing the input impedance of the amplifiers as well as the preamplifier's volume pots (from 250K to 500K). Any sonic problems? So far I have detected none with certainty, but I believe there will be some ultra-demanding records (or CDs) that, at certain times, can challenge the Frankenstein beyond its capabilities (especially in my large room). This belief has been confirmed by Israel Blume, who designed both the amplifier and the speaker. However, 1% or so of my records don't trump the other 99%, and even those 1% will still sound better, most of the time, with the Frankenstein playing solo.

June 2009 Update- I recently conducted an audition of the Ars Acoustica monitors, in my own listening room, for the person who ended up purchasing them from me. Based on this audition, I concluded that the Ars had a larger advantage in "Image Focus", compared to the Pure Reference, than what I had written in my initial review. I have since updated the review to reflect this reassessment.

Future Plans- I still plan to bi-amp the Pure References with the Dragons, but this time going direct, and without the Behringer Digital Crossover. Based on prior listening sessions, I believe almost all of the sonic problems I (indirectly) heard, and described above, came from the Behringer (between its two digital/analog conversions and its solid-state analog stage). It may be possible to get "the best of all worlds", or at least the minimum possible amount of compromises, with the combination of the Frankenstein and Dragon (on the subwoofers), though it will obviously come with a monetary price.

I also want to make clear that while the Behringer, or any other electronic crossover, will no longer be used in my current system, they can still be useful, and even necessary, in other systems. It all depends on what is required: slopes, levels, equalization etc. In general, the more complex the requirements, the more likely an electronic crossover will be necessary. The Pure Reference's utter simplicity makes such a component not only unnecessary, but also the cause of a serious deterioration in its performance.

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PART TEN- THE "EXTREME" VERSION

The "Extreme" is simply the "Original" Pure Reference, with the exact same drivers and crossovers, but in two separate cabinets (a mini-monitor and a subwoofer), instead of one large floorstander. With the monitor sitting directly on top of the subwoofer (at the front), the Extreme is around 12" shorter, though its subwoofer takes up around 50% more floor space, because it is 4" wider. The price for the Extreme is $ 26,000, compared to $ 22,000 for the Original.

The big questions are how the Extreme compares* to the Original, and whether the $ 4,000 price differential is worth it (since the Original will still be available)?
Now, as to its performance...

*Both speakers were auditioned with the exact same components, and they also had identical positioning. Further, a number of my visiting associates heard these speakers and verified my observations.

The Original Versus the Extreme

The Extreme is superior to the Original in a number of areas, equal in others and inferior in none. A typical "neighbor", or "brother-in-law", would not be able to distinguish one speaker from the other, but any experienced audiophile should easily hear the differences. In every instance, but one, the sonic differences between them are minor, meaning they are "noticeable", but not "obvious", unless you are an exceptionally discerning listener, or are intimately familiar with their sonics (as a normal long-time owner should be). I will deal with these minor improvements first.

The Extreme is a little cleaner, more immediate and faster than the Original. In short, the Extreme sounds even more like a top electrostatic, such as the Martin-Logan CLS (in its greatest strengths), than before. While its overall tonal balance, perspective and neutrality are the same as the Original, the Extreme does have a small reduction of those tiny frequency aberrations which are unavoidable in every speaker design. These deviations are too subtle to even describe, but they still signal you that a mechanical device is reproducing the musical instrument, rather than it being the real thing.

As for the frequency extremes, the highs are the same, though the bass appears to be just a touch more extended, and with a little more weight and body to it. The quality of the bass is also slightly improved, being, once again, a little more articulate, controlled and defined (see Addendum 2 below). The quality of the highs is also better, but it's even more subtle. This time, a very tiny resonance, only barely (and occasionally) audible with very specific frequencies (flutes, violins and sopranos), has now been effectively eliminated. (Since a very similar resonance was slightly more noticeable with the Ars Acoustica System Max, I wasn't able to isolate the cause of the residual problem when I first heard it being reduced with the Original Pure Reference.)

I saved the best for last, because there is one area that the Extreme is significantly superior to the Original: Image Focus. In my review of the Original Pure Reference (PR), I mentioned that my ultimate references for image focus were the Morrison & MBL, which are omni-directionals. Just behind them was the Ars Acoustica, which is the speaker that the PR replaced. The PR, as good as it was, still noticeably lagged behind all of them. This is no longer the case. Now the Extreme is in the same league as the Ars Acoustica. (I lived with the Ars for 10+ years, and just heard it again in June 2009, so I have high confidence in my memory.)

There is one small difference between them that I have picked up, and it's actually in the Extreme's favor. The Extreme is slightly better focused at the lateral extremes (to the left of the left speaker and to the right of the right speaker) than the Ars. In fact, the Extreme is about as good as I've ever heard, even including the Morrison/MBL, at the outer edges of the overall soundstage. (The Morrison/MBL are still the undisputed "champs" in the large middle.) I don't believe the soundstage itself is any larger, but it is better "organized", so it may appear bigger because it is more convincingly "seen" and "understood".
This brings us to the second "big question":

Is the Extreme worth the extra $ 4,000?

This question can only be answered by how much you value the various improvements. In my own case, the improved image focus alone makes it worth the extra money, with the rest being "icing on the cake". The bottom line for me is simple: I can't go back to the PR.

However, other audiophiles, who don't value "imaging", may have a very different perspective. In fact, unless you truly value imaging, I would most likely pass on the Extreme, unless either:
1. You just must have that last degree of purity, speed and detail etc., discussed above, or
2. The added flexibility of having two separate cabinets is important to you, especially if you want to "double up" the speakers one day, and/or place the subwoofers elsewhere in your room, while optimizing the position of the monitors on their own.

Then there is one last question: What if you already own the Original PR? Should you spend something like $ 10,000 to trade up? For me, I don't feel it's worth it, unless you are an imaging "enthusiast", meaning someone who is actually bothered by the PR's imaging performance, but otherwise satisfied. Other than that, the differences I've described are simply too minor to justify that kind of money.

Conclusion

The Extreme is a welcome improvement over the Original Pure Reference. If I was asked to make an analogy, I would say that most of their differences are the equivalent of "turning a page or two", while the Image Focus improvement is the equivalent of an entire "new chapter". In the final analysis, the Pure Reference, in its Extreme form, is another step closer to the music, and a step further away from the "mechanics".

Addendum 1- The Actual Design Details

The advantages of separate cabinets should be obvious to anyone, at least in theory. Those advantages are why all of my reference speakers had them for the 3 decades before the arrival of the (Original) Pure Reference. Further, and at my request, Coincident owner, Israel Blume, also the designer of the Extreme, has sent me the specific details which should help explain the reasons for the sonic differences mentioned above. Here is Blume's letter (my bold):

"I would like to discuss briefly why the Extreme will sound better, since many may wonder why the 2 cabinets make a difference.

The benefits are:

1. Separation of the enclosures reduces vibrations and enhances cabinet rigidity. Sonically this translates to greater purity and transient precision;

2. Monitor- The connection from the woofer to the binding post eschews any wire at all. The crossover inductor is a direct, hardwired connection to the driver and the binding posts.
The PR requires a 5 ft cable to connect the crossover to the binding posts.
The wire connecting the tweeter to the binding post has been reduced from 5 ft in the PR to 4" in the Extreme.
The small Monitor enclosure (just large enough to house the 2 drivers) reduces diffraction affects dramatically, which results in a more open soundstage with greater focus.

3. SubWoofer- The wider stance (13" vs 9" for the PR) results in greater physical stability, which reduces micro movement of the enclosure. Furthermore, the extra width places the back of the side firing woofers 4" further away from the enclosure wall. This reduces reflections back to the woofer, which slightly reduces non linear cone motion at very high SPLs."

Addendum 2- Break-In and Set-Up

Based on my experiences with the Original Pure Reference, the Extreme will require around 300 hours of play for full break-in. This was eventually verified when I also reached 300 hours with the Extreme.

As with the Original PR, I have changed the incline of the speaker, so that the tweeter is a little further from the listener than the midrange driver. I found this change improves the driver integration, making it sound even more seamless at its crossover point. This must be done in a manner which does not compromise the stability of the speaker. The sonic advantages of doing so are most noticeable if the listener is relatively close to the speaker (8 to 12 feet), which means that at a listening distance of 20' or so, there may not be much (if any) of a noticeable improvement.

As for separating the cabinets, I originally used (4 small pieces of) "Blu Tac" between the monitor and subwoofer, which Israel Blume uses himself and suggested to me, but now I use a rubber like compound. I also have a 1" metapolymer plate sandwiched between the two cabinets.

Finally, I have been using the Coincident Frankenstein M300B Mk. II exclusively with the Extreme, full range, as I had with the Original PR for the last 8 months (to respect the principle of "continuity"). Accordingly, my impressions of their comparative bass performance are based completely with this one amplifier. I must note that the Frankenstein's bass reproduction, as amazing as it is for its low power rating (8 watts), does not equal what I heard with the Coincident Dragon 211PP with the Original PR. The Dragon had greater extension, weight, control, impact and authority. However, it may take relatively demanding music to demonstrate some of these qualities. I must assume that those same improvements will also be noticeable when the Dragon is used with the Extreme's subwoofer, but I don't plan to use this combination until the Extreme is fully broken-in.

Addendum 3- The Sloped Monitor

This latest update only concerns the monitor part of the Extreme.

As I mentioned above, I used the (supplied) "extender feet" to slope back the original speaker, with the goal of having the tweeter positioned further behind the midrange, for better time alignment (and focus). I later did the same with the Extreme monitor. Now, it turns out, Coincident has a new version of the PR Extreme monitor which is sloped back (one inch less depth between the bottom and the top), and I've had a chance to audition these sloped monitors in my own system. (In every other manner, they are exactly the same.)

The result is a very small improvement in image focus. However, you must remember that my monitors were already sloped back somewhat in the first place (by raising the front of the speakers with the extender feet), so there should be a slightly greater improvement in other systems. Further to this, the "should" requires more explanation...

Creating a slope, for time alignment, artificially (as I did earlier), or with the actual construction of the speaker itself (as with this new sloped PR monitor), will provide an improvement in image focus, though mainly at close distances; 12 feet or closer. However, the further the speaker is located from the listener, the less noticeable the improvement in focus will be. In fact, I doubt there will be any improvement at around 20 feet or more.

In short, the closer you are to the monitors, the more noticeable the improvement with the sloped version, but I also need to make this perspective clear; Unless one is sitting very close (8 feet or less), the overall improvement with the sloped monitors will usually be noticeable, though subtle. So, for most listeners, this change will be considered a refinement, which is always welcome, and only rarely will it be a "big deal".

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PART ELEVEN- "THE DOUBLE" EXTREMES

In December 2009, I discussed the new "Extreme" version of the original Coincident Pure Reference (PR), which consists of two cabinets (monitor and subwoofer), instead of one. Within this relatively short post, I also mentioned that one of the advantages of having separate cabinets was the ability to "double up" the speakers (immediately or sometime in the future). Well, I now have such a system in my home, and with enough listening hours and break-in to make a report I am confident in.

An Explanation First

"Doubling Up" is simply getting a second pair of the Pure Reference Extremes (PRE), and then deciding how to place them in your room. If the monitor is currently sitting on top of the subwoofer, but you now want to stack the subs, then you will have to move the original subwoofer back and then place the second sub directly on top of it. However, if your room is large enough, you may want to place the second subwoofer besides the first sub (with the woofers facing in a different direction). If you do decide to stack the subwoofers (which I did), then...

The original monitor, now without its "stand", will have to be placed on a custom made stand (which is available from Coincident) and the second monitor placed directly on top of it (but upside down only), so that the two tweeters are in close proximity to each other. Blu-tak should be used between the second monitor and the lower monitor and the lower monitor and the stand, which will make them feel like one solid piece (instead of three). Then comes the really difficult task of stacking the subs.

The subwoofers are 175 lbs each, so almost everyone will require some help*. The initial subwoofers should be well placed first, with their Extender Feet re-secured after they are moved. Damping material must also be used between the two subwoofers. I used a condensed artificial rubber, though Blu-tak is also acceptable. Importantly, all the speakers (monitors and subwoofers) are wired together in parallel.

Speaker positioning- I originally placed the stacked monitors exactly where the single monitors were located. However, I ended up making two critically important adjustments over (one year's) time.

First- While the single monitor was aimed at the outside of the listener's shoulder (right monitor/right shoulder), the stacked monitors ONLY sounded their best when they were aimed straight ahead. This change was probably necessitated by the different radiation pattern of the Doubles.

Second- The listening distance was also changed: In 2010, my listening position was 12 feet from the speakers (stacked monitors). In 2011, this was changed, in two separate increments, to first 11 ft. and then eventually to 10.5 ft. (including moving my listening couch forward).

*I received the gracious assistance of Jean Nantais (Lenco).

The Listening Results

With everything now broken-in, and with verification from several objective, competent and experienced listeners, I am confident that my observations and descriptions below are accurate. First of all, there are no sonic* "downsides", which I admit initially surprised me, since I was concerned about a possible negative interaction between the two tweeters*, even though they are in close proximity to each other (because the second monitor is upside down). Every difference we did hear was for the better, and there is a critically important "bonus", which I will save for last. Here are the specific improvements when using the "Doubles":

*There is a practical downside though. The "sweet spot" has been narrowed down to really only one listening position. This is due to the combing effects of the two tweeters, which can be minimized at only one position.

Greater Efficiency- To be exact as possible; 3db more, which places the doubles at 97db for 1 watt. Further, and most importantly, the efficiency in actual practice matches the above specification, which doesn't always happen with speakers, for various reasons.

Greater Purity- This is audible at all times, but it's especially noticeable at higher volume levels. This makes perfect sense, since all the drivers are now working at 50% when matching the same volume levels of one pair of the PRE. Just as important, the amplifiers are also using only half power to match the same volume level, so they are also producing less distortion. In practice then, there are two theoretical reasons why the speaker should sound purer, and they do. I obviously can't distinguish between the two of them while listening. I can only report the final results and make my best effort to explain them.

Superior Immediacy and Presence- This is somewhat subtle, but still noticeable (most of the time). It may have something to do with the greater purity described above. It's not a "big deal", but it's still real.

More Natural "Substance"- I purposely did not use the normal word "body", because this would obviously infer that the PRE is "lean", which it definitely is not. In this instance, the existing "body" feels like it has more solidity and weight*, though without any sense of "heaviness". I've seen the word "density" used by others, but I prefer the word "substance" to describe what I am hearing. This is because I also feel there is actually more harmonic and low-level information being reproduced as well. Even further, the individual images are also somewhat larger (see below). So, I feel I have to use a new word (for me) to describe this combination of improvements.

I also would like to stress that this added "substance" is completely natural, meaning it is reflective of live music and sound, and is in no manner "euphonic" (which I consider a distortion, however pleasing it is to some).

*From a different perspective, it is easier to physically "feel" the musicians' presence, just as you would feel something actually in your room.

Superior Bass- The Doubles go (a little) deeper, and with more noticeable weight and impact. This should not be a surprise, considering they also have double the air-moving capability of a single pair. The quality of the bass is also better, but the improvement, in this instance, is relatively subtle.

Larger Images (and Sense of Scale)- The depth and width of the "soundstage" are about the same as the PRE, but the individual images are larger, mainly in height. I believe that this change also effects the sense of extra "substance" discussed above. It also provides a larger, though still natural, "sense of scale" with many recordings. Despite the larger image size, there is no compromise in the image focus or any added homogenization. In fact, the Doubles also have...

Superior Separation- There is a slightly greater sense of separation of the instruments and singers, at all volume levels, though it's most easily noticeable at higher volumes. This may be another byproduct of the Doubles' greater purity, itself caused by the 3db higher sensitivity.

Superior Dynamic Gradations and Contrasts- This is a further improvement over an already strong suit. The dynamic capabilities of the Doubles are simply breathtaking, even at lower volumes, where the sense of dynamic "tension" is critical, especially for acoustical music. At higher volumes, the Doubles are completely effortless, even with low powered amplifiers. Only the finest horn systems can compete with them overall.

And finally the "trump card", which is the primary reason why I am so enthusiastic about these speakers, and have decided to keep them. This is one of those situations where the whole becomes greater than sum of the parts...

Subjective Responses

Besides myself, 4 other experienced listeners, with widely different backgrounds, have now heard the PRE Doubles in my home. Naturally, we've all had a subjective response to them. However, there are two surprises when it comes to these "responses";

(1) They were all the same and
(2) In each instance, they were unprecedented for the individual listener.

I rarely focus on the typical subjective responses of audiophiles, to a particular component or a system. This is because it is now much too common, easy and tempting to enter weasel territory (it's "involving" or "not involving"). This circumstance is quite different. Not only were the responses unanimous and unprecedented (for all five of us), but their very nature was also both risky and encompassing. Here are the important details:

Jean (Lenco) Nantais was the first of us to "go public". Nantais had already heard a single pair of PRE for two days, but this was the first night he and I heard the Doubles, having just assembled them earlier that afternoon. After a couple of hours of listening, we had now heard a variety of music; soft and loud, simple and complex, delicate and crude, large and small. While I was changing records (our only source that evening), Nantais said something to me that I was feeling myself, but was still not able to put into words yet (and I was also somewhat embarrassed by this same feeling).

To paraphrase Nantais; "This is the first time I've ever heard an audio system with no limits. It does everything". After hearing Nantais' words, I was silent for a while. Finally, I told him that I agreed with him. I told Nantais that these speakers gave me a feeling of confidence that there was nothing they could not do, and that this was the first time I've ever experienced this, in my own system, or anywhere else. Further, while it obviously took the entire system to achieve this highest level of performance, it could only be the speakers that were able to finally put it "over the top". Let me explain...

From my experience, there are now (and have been in the past) many "big speakers" that can play loud (cleanly), sound "big" and go low and high, but not without easily noticeable problems, especially at lower volume levels. However, the PRE Doubles can equal these "big speakers" in their mentioned strengths, while avoiding their (once thought unavoidable) problems. This reality became increasingly clear to me that evening, especially after I had heard a few particularly challenging records, now forgotten unfortunately*, that were reproduced in a manner which I had never experienced in the past.

Then, in quick order, came the confirmation from three other listeners. A week or so after Nantais left, I had two more visitors (who are brothers), both of whom had heard my system in the past (one of them had worked in an audio store for a few years), and were no longer easily impressed. After a few hours of listening that evening, both of them were literally speechless for a while, and then they both repeated what Nantais had first said, and almost word for word: "This system can do it all!" I informed them that the turntable guy (Nantais) had said the same thing, and they weren't surprised, since they both felt that it was an obvious conclusion.

Then, a week later, my final visitor came. He was the toughest critic of the bunch, by far. He had been an executive of a classical recording company in the past, in the LP/CD business for decades and someone who had been to the most famous concert halls all over the world. He was also very familiar with all of my audio systems of the last 25 years, including the original Pure Reference and the PRE, which he heard in my home.

Well, lightning struck again, and after hearing the fabulous Kodaly LP reissue**, and choosing his words carefully, he told me he had never experienced anything like this in his life, including all of my previous systems, no matter how good he felt they were at the time. He used similar words to the others; "it does it all" and "there's nothing it can't do" and "I don't hear any problems at all, no matter what." He couldn't have been more impressed and moved by what he heard.

Finally, to clarify any potential "issues" concerning the above; outside of the two brothers, none of these listeners knew any of the others, except me of course. More importantly, I said, and did, absolutely nothing to elicit or encourage any type of positive response, let alone what I actually heard. The bottom line- These personal responses were completely spontaneous, which is why I believe they are so powerful and meaningful. This is the only reason why I am even reporting them in the first place.

*They were probably the records I described in my Lenco Reference Review/Essay

**Decca SXL 6136 "Music of Kodaly" Hary Janos Suite ("Battle of Napoleon") Speakers Corner

Conclusions

The "Doubles" version of the Pure Reference Extreme is unquestionably the finest loudspeaker system I have ever heard. The performance gap between the Doubles and other speakers I've heard, with the sole exception of the PRE itself, is obviously now even larger than I've described in the past, and that includes all of the speakers I auditioned at the 2004 CES, at any price. So, while the cost of the Doubles is "high" ($ 50,000), its overall performance level is also unique, and any potential competitors that I'm aware of, which use similar drivers and all-out cabinets, will cost considerably more ($100K+).

In short, in the dynamic speaker universe, its flaws are exceedingly minor, barely noticeable and basically "nitpicks" in relative terms. Even the most critical listeners will be completely satisfied with this speaker, no matter what other dynamic speaker they've heard in the past, at any price. The only exceptions being those audiophiles who prefer a completely different sonic presentation; meaning either dipoles (ribbons or electrostatics) or omni-directionals. In fact, I believe it will take a radically different technology to noticeably outperform this speaker (something like the Apogee Definitives, which cost $100K+).

It also has other important advantages...

Unlike any of its potential competitors, the Doubles can be purchased in "stages" (one pair at a time), which makes the single PRE even more attractive on its own, because of its increased flexibility. This is the only reason why I was able to purchase them myself, since I already owned a pair of the PRE. The Doubles also have placement advantages, since the subwoofers and monitors are not attached to each other. This can be critical in the goal of optimizing its performance as well as fitting them in unusual rooms and satisfying personal requirements.

Even more important, the Doubles can be easily driven, full-range, including the deep bass, with a good 300B SET amplifier. Personally, I'm so satisfied with the results I'm receiving with the Coincident Frankenstein 300B, that I haven't bi-amped* the Doubles even once, and I play them at pretty high volumes at times, in a relatively large room. This combination is only seriously compromised at the most ear shattering listening levels (105 db+), or when playing the most challenging recordings. For those audiophiles who regularly listen at those levels or higher (I'm not one of them), I would instead suggest using a more powerful amplifier of very high quality (Coincident Dragon, ASL Hurricane, Canary 339, Altec 1570 or DeHavilland 845 etc). The speakers themselves can play, cleanly, at levels which can be ear damaging, but abusing this capability would be foolish, and a tragedy for the listener.

In the final analysis...

I realize that many readers will consider such a large ($50K) investment in any component, even a speaker system, to be "crazy". I would have felt this way myself not too long ago, mainly because none of the speakers I heard at such prices (or even much higher) was superior, overall, to a few speakers I heard that cost far less ($20K or under). More importantly, none of the mega-priced speakers ($50K to $250K+) I heard was capable of "doing it all". This entire paradigm/dilemma has changed with the PRE Doubles.

The Doubles definitely "do it all". This is why I made such a "big deal" about all of those personal responses above, and they're the main reason why the Doubles are my ultimate speaker "Reference". Even if and when something proves to be superior to them in the future, it will not change the fact that they were the first speaker which "crossed the Rubicon" in my experience. It will also not change the fact that their performance is so satisfying and encompassing, that our typical and unavoidable audiophile "concerns", conscious and unconscious, slowly become just a memory. Depending on your perspective, this could be liberating or frightening, or maybe even both.

*Based on all my experiences with the PRE, I am still convinced that the Doubles will sound their very best only when they're bi-amped. While most source material will still sound basically the same, bi-amping will be a noticeable improvement in many instances, and, with the most challenging recordings (Shostakovich Symphony 11, Second Movement), there will be a dramatic improvement. (9/10)

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System Pictures

Here are pictures of the Double Extremes in my listening room. The top three pictures were taken in Spring 2010, while the bottom three pictures were taken in Spring 2013 (when they were also bi-amped, aimed straight ahead and moved forward, along with my listening couch):

Spring 2010

New System 2

New System 3

New System 5

Spring 2013

System Spring 2013 001

System Spring 2013 002

System Spring 2013 003

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BI-AMPLIFYING THE (DOUBLE) EXTREMES

A REPORT ON THE COINCIDENT FRANKENSTEIN AND DRAGON AMPLIFIERS

(DRIVING THE PURE REFERENCE EXTREME "DOUBLED" SPEAKERS)

I actually made these comparisons some time ago, and there were no surprises, just a confirmation of past results and observations. I decided to delay writing about this subject until I heard one final important comparison, with an associate present. I wanted to place all the relevant information, on this one subject, within only one post, which would prevent future confusion and wasted time. Here is what I/we heard, virtually none of which should surprise anyone:

1. When played full-range, the Frankenstein amplifiers were preferable overall, most of the time, and only demonstrated their shortcomings, in an obvious manner, on the most challenging of records, which required very high volumes and/or demanding bass notes. They excelled in purity, transparency, naturalness, ultra-low sound-floor and a lack of an "electronic character".

2. The Dragon amplifiers, while outstanding performers, were only superior in attaining ultimate volume levels, and in the bass frequencies, though the latter improvement was usually subtle, and only obvious on music with serious bass challenges. The only surprise we ever experienced, though it was heard before, was that the Dragons were not superior in dynamic intensity (except when the Frankenstein was over extended), even though this quality is one of their greatest strengths.

3. The best sound we heard, without a doubt, was when the (Coincident Pure Reference Extreme Doubled, or CPRED) speakers were bi-amplified, with the Frankenstein on the monitors and the Dragon on the subwoofers.

In the end, choosing between the amplifiers, assuming the speakers are the Pure Reference, or something similar, comes down to "quality versus quantity". If the listener requires the Dragon's extra power for a variety of reasons; an unusually large room, high listening levels, and extra challenging music, plus "peace of mind" that the amplifiers will never "give up" under any circumstances, then I would get the Dragons. Otherwise, the Frankensteins are to be preferred.

It must be kept in mind that the Dragons cost more and that they will also easily drive almost any speaker made, while the less costly Frankensteins are really "specialists", but are unmatched, in my experience, with the right speaker. For the best of both worlds (with the CPRED or any Pure Reference for that matter), which unfortunately comes with a monetary price, we must now discuss bi-amping.

The Sonic Advantages of Bi-Amping

There are several sonic advantages that are gained when bi-amping. The most easily heard improvement, even by a non audiophile, is in the bass, if and when a challenging recording is played (Shostakovich Symphony 11, Second Movement). However, while this improvement can be definitely described as "dramatic" at times, it is also a relatively rare event, constituting maybe 10% of my recordings. In truth, most of the time, the improvement in the bass is subtle, and many times hardly even audible. This is because the CPRED is an extremely easy load, and the Frankenstein has exceptional bass reproduction, especially for a 300B SET amplifier.

Fortunately, there are other improvements, which are both more common and much more satisfying (to me anyway) in the long run, even though they are less obvious than hearing overwhelming bass impact etc. They are caused by the Frankenstein amps now driving the monitors alone, and no longer having to also drive the subwoofers.

While never "dramatic", the monitors sound cleaner, faster, more transparent, detailed, immediate and effortless, less homogenous and even more cohesive and intelligible. These improvements are noticeable with almost all recordings and at all volume levels, and cumulatively, once heard, are such that it would be "painful" to have to go back and live without them. These results are not surprising, since they were also heard with the original (single box) Pure Reference, and (going back in time) the Ars Acoustica System Max for that matter.

Finally, the Dragons provide one other improvement that many audiophiles may find very important, even though it is not obvious at first. In comparison to the Frankenstein, on many recordings, the Dragon has somewhat more "weight". This is not surprising, but at the same time there is also a sense that some instruments have grown closer to their "real life" size. This is especially noticeable with instruments such as a double bass and large drums. How a listener responds to this change is obviously personal, but for me, it can be quite thrilling at times, and also helps make the final sound even that much more realistic.

In Conclusion

The "bottom line" of the totality of our observations is simple: Bi-amping has its (monetary and other) costs, but with a speaker such as the Pure Reference, or others with similar accuracy and resolution, it is absolutely indispensible to achieve all their potential performance.

2011 SYSTEM PERFORMANCE UPDATE

The Sum of the Parts...

During the first few months of 2011 I made several noticeable improvements to my system:

1. Adding the Coincident Statement Line Stage
2. The Lenco Spring (Replacement) Modification
3. Bi-amping the Coincident Pure Reference Extreme Speakers
4. Repositioning the Coincident Pure Reference Extreme Speakers (see above for details)

The accumulated improvement of these four changes has been dramatic in a number of important ways. In fact, at this time, I am experiencing a level of performance noticeably beyond anything I've ever heard in the past, including any of my previous systems, in private homes or at audio shows, regardless of the price, scale and ambition of the components and/or systems.

However, this short article was not written to "crow" or celebrate. Instead, I would like to discuss just one element of the performance. It epitomizes what has been achieved. It is also the easiest to explain and the least likely to have been predicted, which thus makes it the largest surprise for me (and maybe others). I also believe it sets a precedent of sorts, at least in my experience, which is the primary reason I feel I must share it.

The specific improvement I am referring to is the area of "speed and articulation". Further, I believe only an actual example will illustrate what I am observing, and will also provide a "reference point" (or "control") for others. While I heard this improvement with virtually every LP I played, one record in particular made it so obvious that it was simply impossible to ignore. This LP is the well known Praetorious Tanzmusik on Archive 198166 (I played the 180 gram Alto Reissue).

Listening to the first four or five cuts (dances) on Side One of this LP are all that is necessary to understand the accomplishment. The instrument to focus on is (their ancient version of) the flute. It is one of the major instruments in the ensemble and the flutist is able to repeatedly play (what appear to be) 64th notes, which come and go like lightning. (Of course, the recording engineer, along with the mastering engineer, should also receive some kudos.)

To make things clear, I've never heard these particular notes as precisely articulated, as they are at present, on any system I've played this record (or the original pressing), and I've heard this recording numerous times, on many systems, for more than 25 years. Until now, I had no idea there were even 64th notes on this recording in the first place, since they were always "smeared", to one degree or another, in the past. Further, as satisfying as this is, there is a serious implication and a much more important issue to be addressed...

What must be emphasized at this point is that I'm hearing this outstanding level of performance on a system that, by "conventional/mainstream audio wisdom", should not be able to accomplish it. My current system consists of a phono source, which then uses tubes in the phono stage, line stage and the power amplifiers, and dynamic drivers in the speakers. However, such an outstanding level of articulation is supposed to be the exclusive domain of digital (SACD) sources, and even then only using hyper-speed transistor electronics (like Spectral) and electrostatic speakers (like Martin-Logan). This "theory", which I previously believed in myself, has proven to be false. This unexpected equivalence is, to me, for once, a real "breakthrough".

The implications of this achievement are serious and must not be understated: This now means that choosing the route of "analog and tubes" does NOT also mean that "second-rate" articulation must be an inevitable consequence of that choice. It may be difficult, and somewhat expensive, to reach the high level of performance I'm now experiencing, but it can be done! That fact is the most important point of this article.

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INTERNAL LINKS

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AUDIO CRITIQUE

THE RECENT FILE

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