March 2024

Eminent Technology LFT8c Loudspeaker Review
Dipole done well.
Review By Jules Coleman

  If you are not familiar with Bruce Thigpen, it's time you were. Bruce has been among the more creative and innovative designers in the audio industry over the past forty years. He began his career by working on what was to become the Infinity turntable, which he followed with the classic and much-admired ET 2 linear tracking tonearm (parts and updates are still available for the model 1, ET-2 and ET- 2.5), before turning his attention to magnetic planar loudspeakers. Beginning with the full-range planar LFT3, he ultimately shifted focus to hybrid designs featuring planar mid and high-frequency drivers mated with traditional cone drivers to handle the lower frequencies. The shift in focus led to the development of the LFT-8 introduced in 1989 and then widely distributed beginning in 1990, the transformative version of which, LFT-8c, is the subject of this review.

Bruce's company, Eminent Technology, is also well-known among computer audio enthusiasts for the highly regarded, award-winning LFT-11 desktop computer audio system consisting of a planar magnetic mid/tweeter combination matched with two 6.5" bass units in a separate sealed cabinet. The LFT-11 was an unexpected offspring of the not particularly well-received 'car radio' planar speakers, the LFT-10. While planar speakers fit nicely into the ambiance of a relatively quiet home office, they were no match for car engine noise, highway, and city traffic, not to mention the blare of police cars, fire trucks, and ambulances.

Not one to rest on his laurels, Thigpen has created a new type of efficient flat loudspeaker, first applied to electric and acoustic guitars to lighten the load of those caught up in the gig-to-gig lifestyle. And just to show his versatility, Bruce has in the past manufactured cones drivers for audio manufacturers around the world.

Wait, There's More!
Recent evidence suggests that humans can hear below 20 Hz. To help realize this potential in home audio applications, Bruce created the TRW-17, which is the first ever rotary woofer, designed as a sub-subwoofer capable of reproducing frequencies between 0 to 20 Hz. As a rotary device, it occupies a small footprint and turns the energy it captures into sound waves remarkably efficiently. This is no modest accomplishment, especially when compared to the challenges presented by the alternative approaches of employing cone drivers even those aided by horn loading, not to mention that building a horn for a normal size driver capable of reproducing comparable frequencies would require the equivalent of constructing a housing development of McMansions. Though an engineering (and perhaps a sonic achievement as well) the current market for the TRW-17 is miniscule.

Achievements to one side, Bruce is also one hell of a nice person, never defensive, consistently open to suggestions, and overall, among the easiest people to deal with in a stressful industry that takes its toll on many talented people. It's been a personal as well as a sonic joy to have been invited to review his most recent iteration of his most enduring contribution.

From Magnepan And Apogee To LFT
The very first high-end audio speakers I owned were Magneplanar Tympanis, a speaker that marked a turning point in home audio music reproduction. Not so much for its sonic presentation, which was larger than life, softer than a form-fitting pillow, though as satisfying as a teenager's first wet kiss. More for its audaciousness and promise. Truth be told, I loved owning them more than listening to them. Owning them proved to be something of an interior design nightmare, as they took up most of the living room and made finding compatible furnishings something of a fool's errand. They also managed to block out the sun on those rare winter days when it appeared. Still, ownership was a source of pride as it provided a glimpse into what the future would hold.

Nor was it an easy feat to find an amplifier both powerful and refined enough to drive them adequately and in a musically satisfying way. I confess to wanting to love them more than I did. Ever hungry for more than I could ever provide, I sensed that my longing for a lasting, more fulsome relationship with the massive, yet seductive Magnepans was not reciprocated.

And so it happened that when my wife and I left Wisconsin with the newborn in tow, we were dismayed to learn that the accommodation awaiting us was little more than a garage converted into what at the time was euphemistically referred to as a 'mother-in-law' home addition in Berkeley, California. Nowadays, these modest domiciles are referred to in both zoning regulations and real estate brochures as ADUs (Alternative Dwelling Units). The better acronym would be NFFFL (Not Fit for Families Living).

The space that otherwise would have been reserved for the Tympani was turned over to our first child, a more than adequate replacement – emotionally if not sonically. For the latter, we turned to Rogers LS3/5a speakers and bid the Tympany adieu.

Over the next twenty years or so, as we found more sizeable living quarters (and though our family grew to fill most of the available spaces), I managed to indulge my affection for planar designs, including other Magnepans as well as Apogees. In each relationship, the speakers proved fickler and more difficult to deal with than I had hoped.

In time, I grew weary of sending one after another perfectly well-meaning and hardworking amplifier into battle with various full-range Apogees, only to resign myself to defeat. Though defeat comes often on the 'audio battlefield', I have been loath to accept it graciously. Instead, convincing myself that I had done all I could to wrestle the most from the Apogees, if only for brief periods, I withdrew from combat.

Each failed relationship with Apogees was followed by a return to Magnepans: MG-I, II, and III seriatim. On each occasion, I was 'seduced only to be abandoned.' Each iteration of the Magnepans provided that seductive midrange with just enough dynamic drive to present music as natural and lifelike – at least at the outset. No initial romance blossomed into a sustainable love affair. All in, and energetic at the outset, in time Magnepans turned sluggish and the sound fattened. The speaker made it clear that they had worked hard enough and long enough to please me, and I sensed they grew annoyed by my musical advances. I grew familiar with this impasse and knew it would not pass. It was best to move on. Ultimately, on each occasion, I did.

I attributed Magnepan's losing their grip and tautness over time to cost-saving steps in the manufacturing process coupled with an understandable reluctance to permit owners to modify the frames and to increase rigidity overall. Nor am I alone in believing that there has always been more available in Magnepan speakers than the stock offerings have presented. As the original designs are now in the public domain, we will no doubt hear several speakers designed very much like the Magneplanars but to tighter tolerances and with more attention to detail from start to finish. I would not be surprised if these speakers were also significantly more expensive, as there is no doubt that the good folks at Magnepan made a conscious decision to get their quite remarkable product in the hands of audiophiles, especially those of modest means.

It was the right decision as there is no speaker company that has done more to introduce music lovers and audiophiles to the magic that home audio systems are capable of. To their credit, the magic Magnepans created in the home has never been the result of hi-fi trickery. But it did come at a cost. So extraordinary was the basic design that every Magnepan speaker has given its owner more value than he paid for but less than it could have.

By the mid-1990s, I was ready to give up and abandon my search for a planar dipole speaker that I could live with long-term. In retrospect, the 1990s were an odd time in audio, especially for someone like me whose experience in home audio was dominated by three different speaker types that shared a singular focus on a natural, life-like presentation of the midrange with a special focus on the human voice and harmonic texture. The three speaker types I 'grew up with' in home audio were the dipoles – Magnepan and Apogee – the BBC authorized mini- monitors – especially Rogers LS3/5a – and the European Holophone System Soprano and Alto, the products of a University of Brussels research project.

The 1990s were not a great period for audio speakers, at least not to my ears, dominated by two distinct kinds of speakers that were all the rage, neither of which I found musically convincing. To my ears, so many of both varieties strayed so far from seeking to create a musically persuasive presentation, that I found myself wondering what had happened to audio while I was not paying attention.

On the one hand, the most popular 'full range" floor-standing speakers during this period featured plump and uncontrolled visits to the frequency nether regions (or gut-punching dynamics of curiously homogenous pitch) accompanied by screeching forays into the sonic stratosphere. I am sure there was a midrange there someplace, but my ears were fully distracted from attending to it by the a-musical, often painful blows being delivered both below the belt and behind the head. The purchase of these speakers should have been accompanied by a manual instructing the listener how to control the bass, which was either fat and ill-defined or unnaturally dynamic and strangely thin, while taking the edge off the higher frequencies. Indeed, someone buying such a speaker was often unable to leave the audio salon without purchasing specially designed speaker cables featuring circuitry that would not help the speakers sing so much as they would reduce the extent to which the tweeter would screech and scream.

Smaller rooms in the normal emporium were typically devoted to the new breed of two-way stand-mounted 'mini-monitors' being hawked not for any capacity they might have possessed to immerse the listener in an intimate emotionally involving experience, but for their capacity to disappear altogether – at least, figuratively. During this period (and to a lesser degree, ever since) the capacity to disappear has been elevated to the level of a fundamental musical virtue – something it most certainly is not. Enjoyable. For many, yes. A 'wow' factor. For everyone (on first listening), certainly. But, essential to conveying musical meaning. Not at all.

Not to mention that the disappearing act came at a cost to overall tonal balance and musical persuasiveness. Though it is easier for a speaker to disappear when it offers so little output in the bottom end, the absence of adequate bass output invariably shifts attention up the frequency range creating a tonal imbalance. Second, the see-through upper frequencies lacked density that, when combined with a non-existent bottom end, combined to render music weightless, hardly what one associates with the power and majesty of music of any sort.

This was not the ideal time for someone like me to have lost his audio way, searching to find an alternative to speakers that for their many shortcomings presented human voices and much of the midrange as close to what is true in real life as one could hope to experience in an audio system.

This unfortunate turn ushered in new additions to the audio lexicon while emphasizing other more familiar terminology in which audio experiences would come to be described, and systems evaluated. Those who fancied the stand-mounted two-way mini-monitors came to speak in glowing terms of upper-frequency air, sparkle, see-through transparency, and fine-grained imaging. Those who took a shine to the floor standers graced by early versions of metallic tweeters and deep if flabby bass emphasized full extension, weight and presence.

I do not recall the term 'musical' figuring prominently in sales' pitches or in audio conversations more generally. Fancying neither of the roads taken by many others, all I could draw on from the lexicon of the day to describe my listening experience was 'discontinuity.'

With one exception, I floundered about for the better part of the next decade, until the early 2000s, when I discovered low-powered tube electronics and vintage loudspeakers and caught the wave created more than a decade earlier by Jean Hiraga in France (and Europe more generally) and Joe Roberts in the United States.

Eminent Technology
The Original Plan And Its Challenges
But this is not the story of my journey once having found the path I would follow for the remainder of my life as an audiophile. This is a two-part story. The first part tells the tale of the one speaker that during my years of aimless wandering gave me hope and brought me solace. The second part tells the story of my meeting up thirty years later with this old friend much as one does (rarely) at a class reunion, only to find that this fellow classmate has not gotten fat or bald, but has in fact maintained grace and stature, if anything, has evolved, and presents as more comfortable with the passage of time than most; an old friend who has even more to offer in adulthood than in their youth.

This, my friends, is the story of my relationship with Bruce Thigpen's LFT –8 line of speakers. When it was first introduced with little fanfare the LFT-8 received complimentary reviews but less recognition than it deserved. I did not listen to one until word finally spread of a challenger to Magnepan's dominance that was worth a listen. The challenger turned out to be LFT-8, and when I saw a used pair for sale, I took the plunge. I cannot recall the electronics I had on hand at the time, but I had held on to several amps, both tube and solid-state that had survived battle with the Apogees and had mated well enough to support a seasonal romance with Magnepans that would eventually turn languid and bittersweet.

The first thing I noticed about the early version of the LFT-8 was that it was tall and narrow and cut a fine figure. It also had an industrial look which was quite becoming. Once the grills – front and back – were removed, the speaker showed off its innards proudly. There was no hiding the many magnets that were employed to move the mylar foil quickly back and forth. One could not judge by looking at just how much air the speaker would move, but the design gave one confidence that the air would be moved quickly and quietly. The wood frame in which the entire speaker was nothing fancy. But the planar that housed the driver elements was. It was firm, strong, and designed to resist movement and to eliminate noise.

From the LFT-8 on, all Eminent Technologies full range loudspeakers have been hybrid designs featuring what the company calls linear field transducer midranges and tweeters mated with an 8" cone woofer housed in a sealed box. The panel is connected to the sealed box, which means that the hybrid design of the original version of the speaker features push/pull dipole linear field transducers and a modestly sized cone woofer in an acoustic suspension enclosure.

One should be excused for assuming that making the hybrid work seamlessly would be a challenge. A cone speaker in a sealed box directs the sound forward as the back wave is suppressed inside the box. In contrast, the planar mid-range and tweeter are both push-pull designs. Even a short throw woofer cannot match the speed of the linear field transducer.

A linear field transducer or LFT has a foil/Mylar diaphragm with conducting traces etched into it like a circuit board that are controlled by magnets in the frame which operate in push-pull. The effect is a presentation that is much more electrostatic in character than one finds in Magnepans or in full ribbon designs. Drawn to electrostatics, Thigpen sought to replicate their way with music – especially the midrange – without the difficult loads that electrostatics typically present to amplifiers and the need to provide an electric charge to excite the Mylar.

Bruce's original idea was to create a full-range linear field transducer panel that would cover the entire frequency range. The resulting project led to the LFT-3, which, while realizing his goal of a coherent 'electrostatic' like musical presentation, failed to extend sufficiently into the lower registers to create an acceptable tonal balance or a full enough musical presentation.

The result may have been disappointing, but not surprising. Planar designs sacrifice some capacity to move air for speed in doing so. Moving enough air to produce a satisfying bottom end requires a very large panel, which creates a number of challenges, some aesthetic, others manufacturing and musical. In my experience, the problem is exacerbated in electrostatics and, by extension in designs like Thigpen's that aim to provide an electrostatic-like musical presentation.

It's hard to generalize, but to my ears, electrostatics are more incisive than are planars. This is true of Quads and early Logan Martins, especially the CLS. This is also true of the Sound Labs. There is always an exception and when it comes to electrostatics, the Acoustat was the exception that, as the saying goes, proved the rule. Incisiveness can be incredibly satisfying musically as it holds the promise of allowing the listener to immerse themselves deeply into the music in a particular way. On the other hand, incisiveness poses a distinctive set of challenges. In particular, an incisive presentation in the upper midrange and high frequencies must be offset by some warmth throughout the midrange and weight in the lower frequencies to present an overall enjoyable (even listenable) tonal balance. With rare exceptions when electrostatics are built large enough to reach deep into the nether regions, the result is often a loss of intimacy and delicacy without securing the benefit of a more satisfying tonal balance.

To its credit, most Magnepan speakers offer a very satisfying tonal balance across the range, but, and I could be wrong – and others may well disagree – I have not found them to be as incisive as other speakers, which, I believe is one reason why they are so easy and enjoyable to listen to, and why some refer to them as 'natural sounding.' When successful on its own terms an electrostatic presentation is capable of delicacy and intimacy on the one hand and substantial weight on the other. Planars are in general more balanced tonally and dynamically overall but less incisive.

If recent history is any indication, the difference between planars and electrostatics may narrow significantly very shortly. I have had the pleasure of listening to the two most recent Magnepan offerings while in their prototype stage of development: the as-yet-to-be-released 30.7 for Condos and the LRS+, which has been released since to rave reviews and extraordinary sales. Ironically, to my ears at least, these two ends of the Magnepan line-up share an incisiveness that is very much like an electrostatic and to that extent differ from their siblings further up or down the line.

Moving forward the challenge for electrostatics will be to maintain their incisiveness while extending their reach, coherence, and tonal balance. There are two available approaches: one is to perfect a hybrid design; the other is to go full range and big. I place the larger Sound Labs in the latter category. Having listened to and reviewed the Sound Lab 845, I can report that the latter solution can be extremely well executed. It is a great speaker. It presents music with convincing density throughout the frequency range. Its dynamic presentation is consistent from top to bottom. It's one musical shortcoming, unsurprisingly, is that its dynamics, while overall satisfying, fall ever so slightly short of the real thing and are just a tad less musically convincing than is every other aspect of its performance.

Eminent Technology LFT-8: Meeting The Challenge
With this background in hand, it is clear what challenges the LFT-8 faced from the outset. Bruce seeks the naturalness and the incisiveness of the best electrostatics, that being the entire point of the Linear Field Transducer. It also means that in order the succeed, the LFT-8c, the sound it produces should be nearly free of distortion, fully coherent within its range of application, and fast in addition to being incisive. So much for implicit design goals. The challenge is to achieve these goals by employing a hybrid design. All this while protecting and preserving the extraordinary midrange presentation. So the challenge includes the goal of an electrostatic-like presentation, featuring the kind of coherence those designs are noted for; the strategy of achieving these goals through a hybrid design; all the while constrained by an analogue of the Doctor's code of ethics 'to do no harm,' – in this case, to the midrange.

The design strategy unfolds accordingly: see how far up and down from the midrange one can extend the linear field transducer preserving the same sonic presentation that it produces through the midrange without adversely affecting the midrange presentation. Work with crossover points and types to extend and blend. Bruce quickly realized in each of his efforts to implement his plan and to secure his goals within the absolute constraint of not compromising the midrange that it was easier to move up the frequency range successfully than to move down it. Along the way, there would be improvements in the extending while blending – both owing to design and crossovers perhaps – but there was only so far down the frequency range the LFT design could go while maintaining size suitable for home use and price comparable to the competition.

This is why a hybrid design was for him unavoidable. The design challenges all followed from this realization. How to achieve coherence and seamless integration while employing different modes of presenting the music. How to ensure that the woofer did not spill over into the midrange and impact its speed, incisiveness, and naturalness.

In all my listening, the glorious midrange remained unaffected by the hybrid design. But... there is always a 'but,' isn't there? But what about the integration of the cone speaker in a sealed box? How did it perform on its own terms, and how did it mate with the rest of the speaker?

To be honest, at first, I was pleasantly surprised, and for good reason. The acoustic suspension loading kept the bass tight and dynamic. The consistency of the dynamics throughout the full range of the speaker was consistent and consistently musically convincing. The extension was deep enough to create a satisfactory tonal balance overall. In short, the enclosed bass loading of the LFT-8 produced solid, well-defined and relatively taut and dynamic bass: a fitting complement to the LFT midrange and tweeter.

In time, however, as I spent more time with the speaker and played diverse types of music through it, I sensed that I was listening to two separate speakers. They worked together fine, in a complementary fashion, but the sense that one was listening to two different speakers was unavoidable. For two distinct but related reasons. There was no escaping that the transition from the LFT panel to the bass was a bit abrupt and needed to be redesigned to approach a more seamless presentation. The second was that the panel was dipole and the bass unit was not. Dipoles are much more open and unrestricted sounding than enclosed alternatives. The difference revealed itself in terms of different levels of freedom and expansive expressiveness.

For the first iteration of a difficult design to implement successfully, the LFT-8 was quite a good start and I loved my time with It. I almost certainly would have stayed the path with Bruce, awaiting improvements that were bound to come in the future had I not found myself pursuing an entirely different path. I had put as much thought into understanding the LFT-8 as the enjoyment I received from listening to it. Since it saved my musical life during the 1990s, I owed it that much in return. Eventually, I left it behind, thankful for the pleasures it provided.

I was too caught up in my newfound love affair with low-powered tubes and horn loudspeakers to reminisce about the Eminent Technology, though I confess to wondering from time to time, how the design might have progressed.

Until... there isn't always an 'until,' even if there is always a 'but.' But this time there was an 'until.' And this 'until' has a name: Steve Guttenberg.

LFT-8c: The Final Frontier?
I've mentioned my respect for and friendship with Steve Guttenberg many times before. He is my choice for United States Ambassador for Audio to the world, provided the post does not require him to change his attire. I watch Steve's YouTube channel regularly, invariably amazed by his ability to remain so genuinely enthused by the experience of reviewing so much diverse audio equipment. It never feels like he is working to earn a living. He is having too much fun for anything that mundane.

Occasionally, Steve displays an unusual enthusiasm for a component that has graced his Brooklyn loft. On one such occasion, Steve was waxing poetic about a speaker he had no previous engagement with: the Eminent Technology LFT-8b. I listened attentively and was surprised by his enthusiasm for the speaker, especially since his most recent top choices for reference loudspeakers had been a horn loudspeaker (Klipsch Cornwall) and an open baffle dipole speaker (Pure Audio Project 15).

Steve gave great marks to the LFT-8b for its dynamics, especially when compared to what he viewed as its competition, namely, various Magnepan speakers. And was quite happy with the integration of the woofer with the panel. The video brought back memories and trusting Steve' ears, pleased me to learn that Bruce had solved some of the integration problems that I found troublesome in the first iteration of the speaker. All to the good, I thought.

I was not yet interested in hearing the speakers in the context of a review but considered visiting Steve's for a listen. By the time I got around to asking him if I might stop by for a listen I was met by another review, again by Steve, and again of an Eminent Technology, LFT-8 loudspeaker. Only this time, the review was of a new model, the LFT-8c which included the DSP capability of the 8b that would allow the listener to adjust the blending of panel and cone, but more importantly, featured a brand-new dipole woofer arrangement.

This is what I had been looking forward to. The weakness in the earlier model was two-fold: integration of the different drive units and the difference in presentation caused by a dipole panel and a front-firing woofer. The DSP would help fine-tune solutions to the first problem. Would a dipole woofer configuration solve the second?

This Inquiring Mind Wanted To Know
I contacted Steve and Bruce Thigpen, explaining my prior experience with dipoles generally and with the first versions of the earlier LFT-8. He graciously agreed to have me review the speakers. I drove my aging SUV to Brooklyn, loaded up Steve's review pair, lunched with the NY audio reviewer 'mafia' bought my wife a lox and cream cheese sandwich from Esse Bagels and headed back to Connecticut flush with anticipation.

The Set Up
I listened to the Eminent Technology LFT- 8c in two quite different systems. The primary system with which I reviewed the speaker included the Mytek Brooklyn Bridge streamer, the Well-Tempered Amadeus Jr Turntable, with Dynavector 20x low output cartridge along with a full complement of PASS electronics: the two-box PASS phono stage, two-box PASS line stage, and 200 -Watt Class A mono block amplifiers. All equipment was placed on a Box Heritage 'rack' and all connections were made using a mix of balanced and unbalanced interconnects from Audience and Merrill Labs. Speaker cables were provided by Stealth.

Because the woofers in the Eminent Technology LFT-8c are independently powered, I also tried the speakers in a system featuring the Lejonklou Boazu integrated amplifier providing 70 Watts into a 4 Ohm speaker load. The Boazu, like the PASS amplifiers was required only to drive the mid-range and tweeter. As I mentioned in my review, the Lejonklou audio components perform very well with interconnects and speaker cables from a wide range of companies. On the other hand, Fredrik Lejonklou's admonition that they perform their best when mated with Linn Silver interconnects and speaker cables is best interpreted as a requirement and not a suggestion. I am not in a position to explain why this is true, though I can report that it is. Once I heard what Lejonklou was capable of when configured as Fredrik insists, its musical performance is extraordinary. Period. Fortunately, Linn interconnects and speaker cables are modestly priced, even inexpensive by contemporary audiophile standards.

Placing the speakers in the room was surprisingly easy. My room is 30 feet long and I begin virtually all speaker setup by applying the rule of thirds, and then adjust thereafter as needed. I then placed the speakers ten feet from one another (midrange to midrange). Once placing my listening chair ten feet away from the speakers, I tried the speakers first with the tweeters to the outside of the panel, and then to the inside. Tweeters outside the midrange created a soundstage that extended beyond the speakers and required additional toe-in to secure a dense, locked-in sound field. Placing the tweeter to the inside of the midrange reduced sound stage width but produced a more integrated but less independently populated soundscape.

Less toe-in was called for, and in fact the speakers sounded quite musically credible firing straight ahead. Though surprisingly different, I found both presentations enjoyable and persuasive. My experience with planar dipoles suggests, however, that placing the tweeters on the inner part of each panel could sometimes create both a tonal imbalance and some glare in the upper midrange. Being a bit risk averse and preferring ever so slightly the wider soundscape, I set up the speakers with the tweeter on each panel set to the outside of the midrange. I employed this configuration throughout the listening period, with both systems.

All planar speakers are directional to some extent and thus reduce concerns one might otherwise have about first reflections and distance from side walls. I managed to keep each speaker three feet from the corresponding side wall. The net effect was a full, uncluttered, layered soundstage of modest width and great depth. The entire soundstage began just behind the speakers and continued to the front of the room. These features of the presentation were consistent across both the PASS and Lejonklou systems.

The Listener's Perspective
In previous reviews, I have not focused much, if at all, on soundstage largely because while it is a potentially enjoyable feature of a system's overall presentation, beyond some straightforward requirements, I do not find it particularly relevant to the most important aspects of the musical experience that audio systems create. The features that are most important for me are the system's capacity to convey the music's meaning and to engage the listener emotionally as well as cognitively. At its best, the experience is immersive, which is to say that the listener experiences the musical performance more from the inside of it, a full participant in it, as opposed, say, to be an observer of it: to be in the experience and not a commentator upon it.

For those purposes, imaging and sound staging matter, but only in some narrowly defined ways. Having notes and players wander all about the stage willy-nilly is distracting at best, making immersion impossible, but also making it impossible to express meaningful content or present a narrative. As linguists know, to express content, make a statement, convey content, or tell a story, words must comply with syntactic and other logical and practical rules. Music is a language. Thus, a certain degree of structure, stability, and order is necessary if an audio experience is to express any meaning at all, let alone provide an experience in which one can be touched by emotion or fully engaged.

Beyond these formal requirements, sound staging as such can be a source of pleasure and joy, even excitement, but not something of musical significance.

In general, dipoles throw a soundstage that appears almost entirely behind the speakers. Because dipoles throw their weight around in opposite directions, they tend to create two distinct kinds of problems to which one needs to attend separately. The first set of problems concerns the sound stage behind the speakers. The second set of problems concerns the musical energy the speaker creates in the space between it and the listener. I am most concerned with the second, but both matter to some degree and we will take them up in turn.

The sound stage behind the speakers is the source of the great illusion of being in the presence of a live performance by 'real' musicians, the main challenge is to reduce, and preferably eliminate diffusiveness in its presentation. Or, to put it another way, the goal is to create a sound stage that is stable, solid, of sufficient density and clarity, while allowing the listener to experience the sense of the performers playing together and not merely separately (but at the same time,) i.e. it must be integrated in the right way. The distinction I am drawing is analogous to that between two individuals walking side by side and the same two individuals walking together.

Most diffusiveness can be rectified by a good speaker setup. But some degree of diffusiveness cannot be so easily cured, for it results from features inherent to the speaker itself. Some speakers are simply more incisive than others. Many planar speakers are less incisive than corresponding electrostatics. To use an extreme example for the sake of illustration: the old Magnepan SMG, which is a lovely music maker, is not incisive at all, whereas the Martin Logan CLS and its progeny are incisive (nearly) to a fault. The SMG often produces inadequately distinct images, and the CLS is prone to produce inadequately integrated ones.

Here the Emiment Technology LFT-8c shines. Properly set up, which is not a difficult task, the speaker creates a remarkably integrated and appropriately incisive soundstage, albeit one entirely behind the speaker – which is to be expected. It achieved this result whether driven by PASS or Lejonklou electronics.

How does the speaker impact the space between it and the listener? It is natural to think of this in terms of the perspective on the performance the speaker provides. In many reviews and audio discussions, this is expressed using the analogy of seating in a symphony hall or other venue: e.g. distinctions between seats in the front of the hall, farther back, and in the balconies, as well as left or right of center location.

While helpful, this approach suggests that perspective is a matter of the distance between stage and seat. I find it more useful to think of the differences in perspective reflecting, not distance as such, but differences in musical energy and capacity for engagement and immersion.

An example from a recent experience I had listening to a wonderful live performance of three works performed by the Bremen Symphony Orchestra at the Bremen Symphony Hall illustrates my view.

This was my first time at the Symphony Hall for a live performance of classical music by the full orchestra. Guest conductor, Matthias Pintscher, normally the maestro of the Cincinnati Symphony orchestra, led the orchestra through works by Ravel and Schumann as well as his own composition featuring a wondrous performance by guest violinist, Leila Josefowicz. The Ravel piece was understated and a bit lax. The Schuman, (his First Symphony) was rousing and optimistic. The orchestra performed both pieces admirably but spurred by the remarkable playing of Ms. Josefowicz, reached its apex on the Pintscher composition: an emotionally complex and consuming piece it presented accordingly.

Though my official seat was in the 13 row just off center I took the liberty of listening to the performances from a variety of locations. What I noticed as I moved about had less to do with spatial or image cues and much more to do with the extent to which the space between the orchestra and my seat was energized, and the impact this had on the form of my engagement with it.

In this hall at least, the musical energy was limited in its capacity to penetrate the space to reach the audience regardless of the piece. By the time I reached the 30th row, the experience was much more like watching and listening to the orchestra's performance on TV than experiencing it live in a hall. Were we to imagine the Hall to be a speaker or an audio system, we would say that it consistently suppressed the musical energy, and in doing so, limited emotional engagement and immersion. It strongly limited the 'perspective' on the musical performance available to those in attendance, and limited the view into the music that was available to all but a very few.

Carrying this thought to discuss the perspective on the music a speaker offers is interesting and revealing. We can distinguish between the absolute limit on the extent to which a speaker energizes the space between the sound stage and the listener and the rate at which its ability to do so correlates with changes in distance between speakers and listening seats. Let me illustrate the difference by comparing four speakers that I have had considerable experience with: Sound Lab 845, Quad ESL 57, Magnepan 3.6, and Eminent Technology LFT- 8c. Importantly, I have had considerable experience with each of these in the same room.

The 845 consistently energized the space in the room with only a modest decrease in energy level even beyond the listening seat 10 feet from the speaker, meaning that for me, the performance was fully immersive at the listening seat. It was no more immersive any closer than that. One gains no special insight into the musical performance through nearfield listening. I have come to see the 845s as among the most musically persuasive speakers I have heard in my home.

The Quad offered a vastly distinct perspective. The drop off in energizing the space between speaker and listener was rapid after five or six feet and dropped precipitously thereafter. It is no surprise, therefore, that some have come to refer to Quads as large headphones. The Magnepan 3.6 created a more challenging set of choices. The large speaker was very energetic nearfield but as the distance from the speaker increased, the energy dissipated, and the image became less dense and more diffuse. This confirmed experiences I and others have had that, despite their size, Magnepans are often most musically most persuasive in a nearfield listening environment.

The LFT-8 had a greater energy output and dynamic presentation than both the Quads and Magnepans. It sustained this output for a greater distance and dissipated at a slower rate. It finished a distant second in this regard to the 12 times more expensive Sound Labs! Though fully engaging and immersive at the listening seat, I found the Eminent Technology speaker to be truly remarkable in a near-field listening environment. I spent the next week listening trying to figure out why. I am not sure I have a satisfying answer.

But, As I Have Written Previously...
I see myself as an 'audio critic' more than as an audio reviewer. My goal is to understand and describe usefully the distinctive aesthetic and phenomenology of listening to music mediated by audio systems. And while I may not have found a convincing explanation for why the LFT-8c proved so well suited to nearfield listening, the experience itself deepened my understanding of how to think of the relationship between speaker presentation and listener experience.

Remember The Pioneer Speaker Advertisement
Do you remember the Pioneer stereo ad (that seemed to show off often during sporting events, and not so much during news shows) in which a listener sitting in a chair turns on his system and is effectively blown away by it – physically? That ad got me thinking about speakers and listeners. There are clearly some speakers that present music to the listener in a way that cannot help but make the listener feel small by comparison. The music is simply overwhelming, and at times overbearing – whatever the music being presented. Music can be powerful and awe-inspiring without dwarfing the intended audience. Don't confuse this form of presentation with image size. Magnepans present music as larger than life on occasion but never as something designed to make you feel small in its presence. The Sound Lab Ultimates dwarf any listener, especially anyone sitting in a chair. Yet, again, they present music on what I would call an entirely human scale.

Some speakers present the music as if it were shot out of a gun, an unrelenting physical assault. Listening to these speakers makes me feel as if I am under attack. It would be incorrect to describe these speakers as champions of energizing the room or the space between listener and speaker. If anything, the sound is experienced more as a weapon than an invitation to dialogue. The aim of such speakers cannot possibly be to draw one into a conversation or a reciprocal experience; or if it is, the designer has chosen an odd way of expressing his desire to invite rapture. Others favor a presentation much like a conversation, an invitation to listen and to respond appropriately. Still others present music as a personal and very private affair that requires attention, that, if given, will be rewarded with insight and intimacy.

It would be a mistake to correlate the physical bearing of a speaker with a particular vision of the relationship between the system and the listener it is designed to realize. Some very large speakers can be quite delicate and intimate in their presentation, while other mid-size speakers can pack an outsized wallop.

Over the course of the three months I spent listening to the Eminent Technology speaker, it became clear that despite its physical presence and its admirable ability to charge a reasonably large room, the LFT- 8c's musical presentation is fundamentally intimate. While considerably more dynamic than its competitors (in both price and ambition), at its core the LFT is a very personal speaker that is as comfortable conveying its message in hushed tones with assurances of confidentiality as it is bringing forth music demanding a rousing endorsement. It is a stout planar design that will work in any reasonably sized room and will reward the listener who wants to be a party to secrets as well as those who want the experience of a coliseum concert.

A Bit More
I came to my review of the LFT-8c primarily seeking to answer one question: namely, does the addition of the dipole woofer configuration solve the discontinuity or integration problem that ultimately ended my relationship with previous iterations of the speaker?

That I ended up learning so much more about the speaker and was drawn to so many other features of its presentation should be enough to answer that question – at least indirectly. Were the issue that led me to abandon the LFT-8 still significant, I would not or could not have listened as carefully to the 8c as I have and learned so much in doing so. So yes, the dipole woofer adds significantly to the consistency of the speaker's musical character. The built-in DSP helps as well.

Is The Problem Solved Completely?
Not fully. We are still talking about a speaker with two hugely dissimilar materials that move air through different mechanisms. No such speaker can be as coherent in its presentation as a speaker consisting of a single driver or a series of panels of the same material and approach to moving air. But at this point, there is no distinctive discontinuity problem: no problem that is any different than those created by conventional speakers featuring drivers of dissimilar materials.

In addition, because the woofers of the LFT-8c are independently driven by a separate amplifier all one's amplifier needs to drive are the panels. While the speaker is not particularly efficient, I was able to drive it to musically acceptable levels with the Lejonklou Boazu integrated amplifier that produces 70 Watts into 4 Ohm loads. I did not find that combination nearly as persuasive as the one featuring Pass Labs 200 Watt Class A power, but I am confident that the speaker will perform exceedingly well with a wide range of amplifiers. Again, this is a virtue not shared by most other well-known and regarded planar speakers.

Finally, I want to emphasize again that the presentation of the LFT-8c is more electrostatic sounding than you might otherwise suppose. It is incisive, articulate, precise, fast, and unencumbered by unsettling levels of distortion. It displays dynamic consistency throughout the musical range. It presents music with density and care. It can light up a room or engage the listener with seductive pillow talk. It can fill a large room but never sound out of place in a smaller one. It is also one of the truly remarkable bargains in high-end audio at a retail price of just $4500. It need never be replaced. All Eminent Technology LFT-8 speakers can be brought up to 8c spec at the factory in Tallahassee at a remarkably reasonable price.

It is common to end laudatory reviews – like this one surely is – by the author suggesting that if you are looking for a new dipole speaker the LFT-8c should be on your list. And while I would make the very same recommendation myself, the truth is that such a recommendation is too weak. The LFT-8c deserves much more attention than the LFT-8 'class' has received over the years. I encourage you to find a way to listen to one. You may just find yourself falling for one of the greatest bargains in audio and a truly excellent speaker regardless of price, and one you can dance with till the end of time.

Interview With Bruce Thigpen Of Eminent Technology
1. Bruce, what stimulated your interest in getting into audio design? 

It was a love of music and at the same time an inability to afford good audio equipment, so as a hobby I decided to try and build most of the audio chain, speakers, turntables, preamps and amplifiers. While the hobby became embedded, with the exception of the turntable and speakers, most of my home projects in high school were not that successful....

2. Did you think at the time that you would devote your entire working life to it?

Not at all, I wanted to be an engineer and started working part time at a local engineering firm during college, they decided to take on the turntable project and I become the project engineer. Outside of the turntable project, that company had financial difficulty and sold the turntable project to Mapleknoll. So in 1982, I decided to take a risk, start Eminent Technology to produce tonearms and a few years later push-pull planar magnetic loudspeakers.

3. Did you see yourself as primarily an engineer applying skills to audio, or someone in love with music who saw a way to express that interest or passion through the use of your engineering skills?

Actually both, I really enjoy listening to music and also trying to find a technical advantage that provides an edge in the marketplace. A product like the TRW-17 rotary woofer has taken us in some very interesting engineering directions, but many of those projects are not related to music.

4. What drove you to work on the basic LFT-8 design for over 30 years? What were the challenges you felt you needed to overcome in the design and do you feel that the design has now reached the goals you had for it?

Loudspeakers are far from perfect and no matter how much you pay, they all have plenty of problems. A listening room offers it' s own set of limitations as well. The basic principles of sound reproduction have been unchanged for many decades. The LFT-8 has always had exceptionally clean midrange reproduction from a line source that minimizes room interaction. With the LFT-8c we are trying to improve the way the woofer interfaces with a room to reduce low frequency room modes.

5. What has brought most satisfaction to you as a designer?

Developing a new way to approach a problem, taking a risk, spending years to make it perform well, then introducing it at a show, watch people scratch their heads to try and figure out how it works. Have some commercial success with enough profit to start the process over again. Starting and owning a company is not easy, but I am still having fun and don't intend to stop!

6. What lies ahead for you at this point?

We developed a new loudspeaker transducer that is thin, light weight, sounds excellent, is loud and very efficient. Our first product with the technology is a musical instrument speaker for acoustic and electric guitar. This loudspeaker technology has a lot of potential and I am very excited about it.

7. Any chance you will return to TT/arm design?

I do try my best to support the existing installed customer base with updates and parts. No other tonearm comes close in terms of cartridge alignment, technical, and adjustment capability. However, the ET-2/2.5 requires a mechanically and technically astute owner or a tremendous amount of customer support. Sadly, today there are not enough dealers available to create customer support for installation and a viable market.

8. What is the easiest way for readers of Enjoy the Music.com to find a pair of your speakers to listen to? 

There are a limited number of dealers, we have adopted a business model where you can purchase speakers directly from us for a trial period and a full refund. While clearly not easy, potential buyers of any loudspeaker should do research and I would be pleased to talk or email with anyone about use of our products. 

Specifications
Type: Floorstanding dipole loudspeaker with active woofer
Frequency Response: 25 Hz to 50 kHz (+/-4dB)
Sensitivity: 83dB/W/m
High Frequency Level: Flat, - 6dB, -12dB at 20kHz smooth rolloff
Impedance: 8 Ohm
Dimensions: 13" x 60" x 1" (WxHxD)
Shipping Weight: 65 lbs. each
Finishes Available: Oak, Walnut, and Gloss Black
Price: $4500 per pair (update previous models is $1600)

Other Features Include:
New dual cavity enclosure with forward 8" and rear 6.5" firing woofers
Updated crossover for the midrange/tweeter sections
Active powered gradient dipole woofers
Low frequency time alignment between the woofer and midrange/tweeter
Adjustable bass level relative the midrange/tweeter sections
DSP to improve low frequency room response and extension
A dipole rear firing woofer smoother bass response in the listening area
Active high pass controls for the mid range and tweeter
New stand design, also compatible with Sound Anchor stands
Software Crossover Updates

Company Information
Eminent Technology
225 E Palmer Avenue
Tallahassee, FL 32301

Voice: (850) 575-5655
E-mail: info@eminent-tech.com 
Website: Eminent-Tech.com