Quad ESL-2912 loudspeaker

If Stereophile gave an award for Loudspeaker We've Most Frequently Reviewed, the hands-down winner would have to be the Quad ESL. The list of past and present Stereophile contributors who've written about the ESL's various incarnations includes John Atkinson, Martin Colloms, Anthony H. Cordesman, Art Dudley, Larry Greenhill, J. Gordon Holt, Ken Kessler, Dick Olsher, Herb Reichert, William Sommerwerck, Steven Stone, and Sam Tellig. The ESL-63 was John Atkinson's personal "Editor's Choice" in 1992, and the ESL-989, a successor to the ESL-63, was Stereophile's 2003 Loudspeaker of the Year and Product of the Year.

As acclaimed as it was for its sound, the ESL-63 also acquired a reputation for unreliability. Quad has had spotty distribution in the US, and for several years had no US distribution at all. That situation changed in 2016, when MoFi Distribution became the North American importer for the entire Quad line. They set up a dealer network, and established a service center that will service all versions of the Quad ESL—going back to the original ESL of 1957 (footnote 1). According to Jonathan Derda, MoFi's national sales and marketing manager, the facility has a technician specifically trained to deal with ESLs, and a good supply of parts. MoFi Distribution is a going concern that distributes products for Balanced Audio Technology, IsoTek, Koetsu, Little Fwend (yes, the nifty automatic tonearm lift), Solidsteel, Spiral Groove, TAD, Dr. Feickert, and Wharfedale, as well as their eponymous record label devoted to ultra-high-quality reissues, Mobile Fidelity Sound Lab.

Memory Lane
My first electrostatic loudspeaker was the KLH Model Nine, which J. Gordon Holt once called "the most nearly perfect loudspeaker we have ever heard." Indeed, it was a very fine speaker—when it worked, which was considerably less than 100% of the time. I came to dread the intermittent buzz that meant that the tweeter was arcing and would soon need to be replaced. Worse still, the speaker's transformer was sealed in wax, and when that malfunctioned it had to be shipped to Boston to be repaired by the technician who specialized in the Nine. (KLH had by then changed hands and no longer officially supported the model.) After the third time this happened (and the problem had been fixed), I was fed up, and decided to sell my Nines while they were still working.

But I wasn't quite ready to abandon electrostatics, and in the early 1980s I read with considerable interest about the then-new Quad ESL-63. I tried a pair and was impressed with their imaging, but thought the bass too mushy, and the speaker generally not as crisp-sounding as a (properly functioning) KLH Nine. I then had a chance to try a pair of used but recent-production original ESLs. I preferred these to the ESL-63s, and the price was right. I bought the ESLs, and they proved to be reliable as well as excellent-sounding over several years of ownership. But they didn't go very low or play very loud, and I eventually sold them and moved on to various speakers that were more conventional and proved to be easier to live with.

Throughout all of this, I retained a fondness for electrostatic speakers, and made a point of seeking them out at audio events. When, at the 2016 Consumer Electronics Show, I discovered that Quad was once again being distributed in North America, with a new top model that promised to remedy the weaknesses of the ESL-63, I decided to check it out.

I'll assume that anyone reading this review is familiar with the basic operating principles of electrostatic loudspeakers—to quote the ever-useful Wikipedia, "a loudspeaker design in which sound is generated by the force exerted on a membrane suspended in an electrostatic field." Quad designer Peter Walker's most important innovation in the ESL-63 was to design the electrostatic stators—stationary conductive elements that carry the amplified music signal—as a set of concentric circles, the signal arriving just a bit later at the next circle outward than it had at the one inside it, the resulting total sound simulating that of a point source. Unlike the ESL, which had damping material behind the rear stators to attenuate the diaphragm's rearward radiation, the ESL-63 was allowed to function as a dipole: soundwaves radiated from front and rear, with no significant attenuation of the backwave.

Although the ESL-63 (and, before it, the ESL) had been well received by audiophiles, many felt it could be improved by judicious modifications. The easiest and simplest modification involved stands that elevated the speaker and stiffened its frame, the best known of which was the Arcici stand (footnote 2). (Sadly, Arcici and its founder, Ray Shab, are no longer with us.) Removing or lowering the speaker's cloth "sock" has been widely regarded as effective in improving its transparency—and producing a singularly ugly loudspeaker. The most radical modification of the ESL-63—by Alistair Robertson-Aikman, founder of SME—was described in Ken Kessler's excellent book, Quad: The Closest Approach. The mod dispensed with the sock, metal grille, and Mylar dustcover, without which—as Robertson-Aikman warns in the chapter he wrote for Kessler's book—"there is high risk of electric shock which can continue for some time after the unit is switched off." The structural modifications included transverse brass beams weighing some 70 lbs and a metal frame, the effective weight of the entire assembly further increased by a 100-lb billet of steel attached to the top of each speaker. Elements of the Robertson-Aikman mod can be seen in the current ESL-2912 ($13,999/pair).

Over the years, Quad has changed hands several times. It is now owned by the International Audio Group (IAG), based in Shenzen, China. IAG promised to remain true to Peter Walker's original concept, but also made changes intended to improve weaknesses in the performance of the ESL-63. They also promised to improve the speaker's reliability, which has continued to be a problem throughout the ESL-63's 36 years of production. Since 2013, all Quad ESL models have been made in China; my impression—based on talking to owners and people in the industry—is that, following some teething problems, the reliability of the made-in-China ESLs is greatly improved.


Under IAG ownership, in 2000 Quad came out with a new sort of speaker that had often been suggested as a way of improving the ESL-63: a taller ESL with the same footprint as the ESL-63, but not so tall as to be unacceptable in the typical living room. This was the ESL-989, reviewed by Larry Greenhill in November 2002, and in May 2003 by Art Dudley and John Atkinson. The current incarnation of this design is the ESL-2912. The ESL-63 had two woofer panels; in the ESL-989 these were joined by two additional woofer panels, one each on top and bottom—and so it is in the new ESL-2912. The additional woofer panels receive the same (delayed) signal as the standard ones. (Quad's current lineup also includes the ESL-2812, which has only two woofer panels; it's essentially the same size as the ESL-63, but incorporates the manufacturing improvements present in the ESL-2912.)

What are the advantages of a taller speaker? There is, first of all, a higher soundstage, which many people prefer, as do I. The elevation of the midrange-tweeter panel also results in less interference from floor bounce, a problem with the ESL-63, noted by some reviewers. But the most important benefits expected from a taller ESL would be in the bass and in maximum output capability. In an e-mail, Peter Comeau, director of acoustic design for Quad and its IAG sister brands Audiolab, Castle, Mission, and Wharfedale, told me that there's a common misconception that the 2912 has "bigger" bass because the extra bass panels add more "power" to the low frequencies. He pointed out that the original papers by Peter Walker and Peter Baxandall showed, in "the Walker equation," that the speaker's maximum SPL is related to or dependent on its height, while its low-frequency extension is related to the size of its panel. "Thus, the extra bass panels provide improved extension at low frequencies whilst the increased height improves the maximum SPL capability of the ESL-2912 (as it approaches the line source at LF)," Comeau wrote.


Other improvements in the 2912 and 2812 over previous ESLs include: 1) a more acoustically transparent grillecloth/sock; 2) physical separation of the power-supply and audio circuits; 3) revised PCB traces, to ensure stability of the power supply; 4) a low-ESR bypass capacitor in the audio circuit; 5) improved, gold-plated speaker terminals; and 6) matching, piano-lacquered, veneered panes on top of the speaker and on the sides of the base, formed from high-density plywood to further damp frame resonances. (For full discussion of all of the changes made since the introduction of the ESL-63, see the reviews referenced above.) The quality of the fit and finish of the ESL-2912 represents a major improvement over the ESL and ESL-63.

Any speaker can benefit from expert setup, and this is especially so for panel speakers, for which the distance from the front wall and the degree of toe-in are particularly critical. Although I have some experience with panel speakers—in addition to owning the KLH Nines and the ESLs, in the September 2012 issue I reviewed MartinLogan's Montis, a hybrid speaker with an electrostatic panel—I welcomed the setup expertise offered by MoFi Distribution's Jonathan Derda.

Unpacking and setting up a pair of ESL-2912s is definitely a job for two people—or even four: Two furniture movers helped us get the Quads from the ground level to my second-floor listening room. To give you an idea of what's involved, the list of "what's in the box" includes, in addition to the speaker itself, a power cord, four spiked feet, four standard feet, four clamping collars, one collar locking bar, a base stabilizer weight, two securing brackets, screws and shake-proof washers, and, de rigueur for high-end audio components, two pairs of white cotton gloves. On the first page of the owner's manual are no fewer than 16 warnings, not including "Follow all instructions."

We first placed the ESL-2912s in the positions in my room that have worked well with a variety of speakers and, with a bit of tweaking, turned out to be good for the Quads. Each ESL-2912 was 41–45" from the front wall (the distance varied because the speaker tilts back), and its outer edge was about 23" from the sidewall. I like a wide soundstage, and Derda's first placements almost did the trick. After he'd left, I moved each speaker about 4" toward its sidewall, which gave me a wider soundstage with no hole in the middle. With the speakers in these positions, the distance between them, measured from each speaker's center point, was about 98", which was also the distance from each center point to my listening seat: an equilateral triangle. The speakers were pointed almost directly at my seat, perhaps just a bit to the side (see photo of my listening room). For serious listening, I routinely lower the blinds, to minimize any reflections that might affect the sound quality. Once I was satisfied with the setup, I installed the ESL-2912s' spikes.

Footnote 1: Though the ESL is often referred to as the ESL 57 or ESL-57, "57" was never officially part of that first model's name.

Footnote 2: See Sam Tellig's article about Arcici's Quad stand in the January 1987 issue:.

Quad Electroacoustics Ltd.
US distributor: MoFi Distribution
1811 W. Bryn Mawr Avenue
Chicago, IL 60660
(312) 738-5025

Dakmart's picture

I don't see a link to Page 2 of this article. Am I too early?

Kal Rubinson's picture

I see it. (Just replying because I want to see if I can.)

Glotz's picture

Quad. Sigh.

Wiscos's picture

Lovely review of a lovely speaker. David Janzen (son of Arthur Janszen who was the main creator of the KLH Nine I believe) has facilities to fix and upgrade KLH Nines and is effectively re-manufacturing these wonderful speakers. With his unique position and understanding of these speakers he has also created, manufactures and sells his own Hybrid electrostatic speakers, the Valentina (bigger) and the Carmelita (smaller). Both of these wonderful speakers are still much easier to accommodate than most ESL monsters including the Quads, and have a combination of electrostatic magic, solid and extended bass, integration between dynamic and electrostatic elements and cosmetic home acceptability that are simply the best I've heard. So much so that I have a pair in the UK! David is in Ohio and his janszenloudspeaker.com operation / website is easy to find. He is also one of the nicest guys you could possibly interact with... Enough praise for one comment I believe!!!

Wiscos's picture

Sorry - it's Janszenaudio.com although the other link usually gets you there...
Looked up the old KLH 9 review from many years back and you can see the high regard that JGH had for Janszen as he/his products are mentioned at least twice.

jtshaw's picture

The photos accompanying this review are quite remarkable. Did Quad supply them? Did Stereophile shoot them? The photographer deserves kudos, and Quad must be quite pleased that the speakers' excellent fit and finish are so apparent.

John Atkinson's picture
jtshaw wrote:
The photos accompanying this review are quite remarkable. Did Quad supply them? Did Stereophile shoot them?

The photo on the cover of the August issue and on p.49 were taken by our regular photographer, Eric Swanson. The other photographs of the speakers were supplied by Quad's US distributor. Th photo of the speakers in Robert Deutsch's listening room was taken by Mr. Deutsch.

John Atkinson
Editor, Stereophile

BDP24's picture

I love ESL's, and have owned original Quads for over a quarter century. While a great loudspeaker, the current Quad has a lot of excellent competition, from the likes of SoundLab, Martin-Logan, Kingsound, and especially Sanders Sound Systems. I say especially SSS because that loudspeaker is imo a considerably better ESL than the Quad, and costs less. I'm afraid Quad's time has passed.

jokeka's picture

I am trying to rearrange my room to be more sound friendly, is it possible to get the measurements of Mr. Deutsch's room? It looks similar and I appreciate him sharing the pic. Similar room pics (space allowing of course) might add nice context to any review.

Robert Deutsch's picture

My listening room's dimensions are 16'X14'X7.5. The photo was taken with a fisheye lens (Sigma 15mm on a Canon 6D) and "de-fished" in software to reduce the fisheye distortions. For another photo of the same room, see https://www.stereophile.com/content/wilson-audio-specialties-sabrina-loudspeaker-page-3

Anton's picture

Jokeka had a great idea. An in-room frequency response would be fascinating.

Listen Up's picture

I have heard Magnepan speakers a bit, and Martin-Logan once and have always enjoyed the lifelike sound of ESLs. I'm not familiar with Quads or the other brands mentioned by BDP24.

How do the Quads (or others) compare to Magnepan?


Gary Osoba's picture

Like others, I throughly enjoyed Robert Deutsche's review. I have been an electrostatic audiophile for years. What I have retained in my current collection:

1) The original Martin Logan Full Ranger ( production prototype CLX).
2) Stax-8x ELS
3) One-off modified Quad 2805's

Re the ML, the prototype was voiced by Gail Sanders to match the sound of the best Stax ELS headphones of the day, and was a dramatically better sounding speaker than the tamed down version which was produced. The prototype dipped below .2 ohms and had wild phase shifts. It presented a nearly impossible load to drive at the time and was essentially a short circuit. Even so, it sounded spectacular on the 1977 Yamaha B-1- an all vertical FET amp which utilized static induction transistors and was way ahead of its time.

Re the Stax, only a few pairs of these were ever imported to the US and no other ELS I am aware of ever tested as linearly as they do over full range. Big, solid panels comprised of 8 elements per side. They are a marvelous speaker but dominate normal rooms.

The specially modified Quads are what I normally listen to. In Robert's article, he wrote: "Since 2013, all Quad ESL models have been made in China; my impression—based on talking to owners and people in the industry—is that, following some teething problems, the reliability of the made-in-China ESLs is greatly improved."

The users I am familiar have said the opposite. And that whatever faults or serviceability issues applied to the UK-made units, the products coming from China are not as well made and result in many more issues. Possibly what Robert is referring to is service issues with the old US importer, as there were many in the latter days. However, regarding Chinese 2805's or 2812's I bought a pair of 2805's (they sound and test better than 2812's) but they malfunctioned immediately after shipping. I had wanted to have them rebuilt and upgraded anyway, so hired Kent McCollum to do so. Kent is very good at this. I specified all rebuilt UK components and we tossed the Chinese material. We also applied all the upgrades to the circuitry that have proven effective. So it's essentially state of the art UK sourced equipment with all practical upgrades. The result is a superb speaker, and after break-in the best Quad that Kent or I had heard. For what it's worth, Kent will rebuild either UK or Chinese Quad components but will not warranty any of the Chinese products. He bases this policy on real world experience.

Possibly the Chinese have made dramatic improvements in their materials, components, and workmanship over the past 4-5 years. That would be good. I do not know if this is the case or not, but wanted to share my experience.


Charles E Flynn's picture

Thanks for taking the trouble to provide such a detailed account of your successful repair/upgrade experience with Kent McCollum at Electrostatic Solutions.

Archguy's picture

Alas, as appealing as these speakers are, every pair I've seen in the market is either on its way to the repair shop or just arrived therefrom.

Separately, the listening room depicted isn't remotely adequate for judging the sound of speakers like these.