Quad ESL-2912 loudspeaker Page 2

I'd been told that the review samples had been used at a show, and had also been played at MoFi's headquarters; nonetheless, their sound benefited from break-in. Over a period of several weeks, playing music as well as various speaker-break-in CDs, I found that the ESL-2912s sounded more open and more dynamic. I also felt that there was some warm-up effect: Before a listening session, the Quads benefited from my playing through them the five-minute "Rejuvenation (rapid refresher)" track from Full System Enhancer & Rejuvenation Disc (CD, IsoTek IBD-CD1).


Which amp?
I had on hand two amplifiers to drive the ESL-2912: McIntosh Laboratory's MC275 LE (tubed, 75Wpc) and Theta Digital's Prometheus (solid-state, 250Wpc). The McIntosh seemed a natural match—its history goes back to the era of the original Quad ESL. And, indeed, the combination provided a smooth sound that was easy on the ears—but perhaps a little too smooth, and dynamically a bit on the polite side. I tried the MC275's 8 and 4 ohm terminals; the sound was very slightly better through the 4 ohm taps, so that's what I used.

On paper, the conservatively specified 75Wpc of the MC275 LE is more than enough to drive the Quads, and the 250Wpc of the Theta Prometheus (500Wpc into 4 ohms) might have seemed like overkill. But I'd had good experience with the Prometheus driving Wilson Audio's Sabrina and Monitor Audio's PL300 II, and, well . . . it was available. In fact, the combination of ESL-2912s and Prometheus was a good one: more dynamic, more extended and better controlled bass, and, generally, squeaky-clean sound. I can imagine some people preferring the MC275 LE, others the Prometheus; I was quite happy listening through either. My comments about the sound of the ESL-2912 are a kind of averaging of the speaker's sounds with the two amplifiers.


As had been the case with the Quad ESL-63s, my most immediate positive impression of the ESL-2912s was of their presentation of space. Voices and instruments were fixed precisely in space with an almost three-dimensional quality. I've heard this type of imaging from other flat-panel electrostatic speakers, including my old KLH Nines, but the trade-off had always seemed to be a very small sweet spot: the head-in-a-vise effect. Some panel speakers—eg, MartinLogan's Montis—counter this problem with curved panels. This broadens the sweet spot, but the downside is somewhat less precise imaging. The ESL-2912s, presumably because of their circular stators and delay lines, produced precise images over a wider sweet spot. Although the imaging was not quite as good when I sat in a chair next to my central listening seat, instead of collapsing entirely it just shifted to the side.

A speaker with dipole transducers, radiating to the rear as well as to the front, has an easier time filling a room with sound than a unipolar design radiating only to the front. The potential downside is interference with and cancellation of the front radiation by the rearward radiation. I've installed no sound-absorbing treatments on my room's front wall, but the distances between the backs of the ESL-2912s and that wall, and between the speakers and the sidewalls, were well beyond the minimums recommended by Quad. In any case, there was no noticeable front/back interference effect. If there had been, I would have expected it to adversely affect the soundstaging. But the soundstage was wide and deep—depending, of course, on the recording. Listening to the "Depth of Image: Acoustic Clicker" tracks on Best of Chesky Jazz and More Audiophile Tests, Volume 2 (CD, Chesky JD68), I could distinguish depth up to 70', which is just short of what I can hear with such topnotch unipolar designs as Monitor's Platinum PL300 IIs.


In view of the history of criticism of the ESL-63, perhaps the most important questions to answer about the ESL-2912 are "Does it go loud?" and "Does it go low?" My answers are "Yes" and "Yes"—with qualifications. The ESL-2912s played loud enough to please me at what I would call realistic levels, but different people have different ideas of what level is appropriate for listening to music. I recently attended a birthday party held in a nightclub, where music was provided by a five-person rock group. I measured the peak level with the trusty Audiotool SPL meter app on my iPhone 6: 103dB (C weighting, fast). I'm pretty sure the ESL-2912s can't produce that sort of sound level—and I have no problem with that: For me, that's too loud. (At the party, to protect our hearing, my wife and I balled up Kleenex and stuck it our ears.)

As a check on the ESL-2912's loudness abilities under more normal conditions, I played Eiji Oue and the Minnesota Orchestra's recording of Rimsky-Korsakov's Dance of the Tumblers, from Tutti! An Orchestral Sampler (CD, Reference RR-906CD), at a level that I considered realistic: 92dB peaks, C weighting, fast. The ESL-2912s took this in stride, not protesting in any way, and with no obvious compression of the peaks. Although some audiophiles think of electrostatics as being suitable only for chamber music or music played at background levels, I found the ESL-2912 capable of much more than that.

What about the ESL-2912's bass response? According to its specs, the two additional bass panels extend the –6dB frequency response to 32Hz, compared to 37Hz for the two–bass-panel ESL-2812. Not having a pair of ESL-2812s on hand, I can't say how the two models' bass performances would compare in my room, but I've heard the ESL-63 and its various two–bass-panel successors often enough at dealers and shows to say that the ESL-2912 sounded more full-range, and was more capable of producing real bass.


The 32Hz synthesizer note at the beginning of "Temple Caves," from Mickey Hart's Planet Drum (CD, Rykodisc RCD 10206), was there—not room-shaking, but a pure bass note, not merely second harmonic masquerading as deep bass. I was able to play this track at peaks of 94dB (C weighting, fast), a level that I feel is about right with this music. Double basses were reproduced with tunefulness and subtle dynamic variations, making me appreciate once again the artistry of bassist David Finck on Sylvia McNair and André Previn's Sure Thing: The Jerome Kern Songbook (CD, Philips 442 129-2).

But the greatest strength of the Quad ESL series, beginning with the ESL-63 has been, and continues to be, its midrange: smooth, revealing without being over-etched, and presenting a virtual open window on the music. These qualities were particularly revealed by well-recorded voices. One of my 2017 "Records to Die For" was Kristin Chenoweth's The Art of Elegance (CD, Concord CRE00148), which combines respect for popular-song performance traditions with a fresh take on some standards. Through the ESL-2912 I reveled in the beauty of Chenoweth's voice and appreciated the subtle nuances of her phrasing. The Quad also excelled at what some refer to as microdynamics, communicating the subtle ebb and flow of the music, orchestral and vocal.


Nonetheless, I heard some departures from strict tonal neutrality, including a midbass emphasis that added to the sound a not-unwelcome warmth. This may have been a function of the speakers' positions in the room. There was also an attenuation of the extreme highs, most clearly evident with percussion instruments, like the ones in Ana Caram's "Viola Fora de Moda," from the Chesky Records Jazz Sampler & Audiophile Test Compact Disc, Vol.1 (CD, Chesky JD37). Monitor Audio's Platinum PL300 II had a more neutral midbass and more extended treble.

One thing I highly value is a speaker's ability not to sound like a speaker. The "speaker sound" originates in the drivers, each of which exhibits a set of resonances—and, if the drivers are in an enclosure, the box adds its own resonances, resulting in a "boxy" sound. Over the years, speaker designers have worked hard to solve this problem, with considerable success. Monitor's Platinum PL300 II, which comprises dynamic drivers in a box, has very little speaker sound, but if you listen very closely, you can hear that it has not been entirely eliminated.


The ESL-2912 has an obvious inherent advantage over box speakers in having no box at all. However, with some music, mostly orchestral, I was at times aware of a kind of drumming sound that wasn't part of the music. I assumed that this was a characteristic of the stretched polyolefin dustcovers. You'll recall that removing their dustcovers is one of the ways Quad ESLs have been modified to improve their sound—but this is an extreme step, and unless your listening room is 100% dust free, it will lead to the speaker being damaged in fairly short order. Not recommended!

I think that the resonant colorations that are the source of "speaker sound" are just something that audiophiles and music lovers have to live with, as we concentrate on the music, not the sound. The surprising thing is not that a loudspeaker contributes to the music sounds of its own that are not characteristics of the recording, but that an electromechanical device can manage to sound as much like musical instruments and human voices as it does while adding so little sound of its own.

Peter Walker began work on what was to become the ESL-63 in 1963 (hence the model designation), but the speaker wasn't launched until 1981. Although Walker died in 2003, production of the ESL line continues, and despite changes and improvements along the way, IAG has remained faithful to Walker's original concept. The price range of $10,000–$15,000—into which the ESL-2912, at $13,999/pair, squarely falls—may represent the sweet spot (well, at least for high-end audio!) for sound quality and value. With their continuous development of the electrostatic principle, especially in the successful integration of two more bass panels, Quad has maintained its position in this highly competitive market. Peter Walker would be pleased.

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.