The Hub: QUAD ESL-57, Some good things last a lifetime.


In nearly 40 years of audiophilia, only a few demos have altered my perspective on audio. The three most memorable demos were significant because of the speakers used: one featured Magneplanar Tympanis, another featured Hill Plasmatronics. The third game-changing demo utilized the speaker which has probably beguiled and bewildered more music-lovers and audiophiles than any other, the original QUAD electrostatic, often referred to as the ESL-57.

Like FIAT and SAAB, "QUAD" is an acronym, representing the military-sounding phrase Quality Unit Amplifier, Domestic. Blair Roger's excellent "Quad ESLs : Then and Now" page tells us that the company we now think of as QUAD got its start in 1936, when Peter Walker founded S.P. Fidelity Sound Systems. Within two years, the company had become The Acoustical Manufacturing Company, producing a portable public-address system. Home hi-fi followed, with a tuner, pre-amp and amp; the majority of production during WW II was the portable P.A.. After the war, QUAD produced a corner-horn speaker utilizing a moving-coil woofer made by British speaker-manufacturer Goodmans, and a ribbon tweeter made by Acoustical.

1953 was a big year for England: Queen Elizabeth ascended to the throne, a British subject climbed Everest, and QUAD introduced the model II power amplifier, a replica of which is still made today. In 1956, QUAD first publicly showed their electrostatic speaker, which had been under development for half a dozen years. Interestingly enough, at the same show Goodmans' chief designer, E.J. "Ted" Jordan, also exhibited a full-range electrostatic loudspeaker (ESL). Unlike Goodmans' design, QUAD's ESL became a landmark product which revolutionized the worlds of home music reproduction, industrial design, and commerce.

The QUAD electrostatic was, like all electrostats, essentially a capacitor. A conductive plastic film which acts as the diaphragm of the speaker is positioned between perforated metal grids. A charge is maintained on the diaphragm, and as the high voltage to the plates/grids varies with the music signal, the diaphragm moves, producing sound. In the QUAD ESL-57, the speaker utilizes a step-up transformer to couple output of an amplifier to the plates. Unlike many ESLs, the QUAD is not a "one-way" design, but has a tweeter panel surrounded by woofer panels on its left and right. This gives the ESL-57 limited dispersion, creating a tightly-focused "sweet-spot".

Compared to most contemporary speakers, the QUAD 'stat produced a startlingly clear and well-defined sound, yet was totally lacking in the etched quality audiophiles often associate with "definition". Its design and construction placed restrictions on both ultimate volume capabilities and bass-extension; rather like a tube amplifier, when the QUAD ESL was overdriven, dynamic contrasts flattened out, distortion increased, and it just didn't get any louder. If the speaker was badly overloaded, however, it was possible for the diaphragm to short out (or "arc") against the grids, producing a crackling noise, accompanied by a flash and a stench of scorched plastic if it was really REALLY overdriven.

Peter Walker himself sought to overcome the issues of limited bass and the restricted "sweet-spot" with his next design, the ESL-63. Design of the new model began in 1963, as the nomenclature hints, but a production model wasn't introduced until 1981! That gives a pretty decent idea of how difficult Walker found it to improve upon his first ESL. The ESL-63 succeeded in producing more bass by utilizing a larger radiating-area and dipole radiation, and a delay-line created a wider dispersion-pattern by initiating the signal at the center of the diaphragm, radiated outward to the edge, mimicking the expanding concentric rings created by a rock thrown into a pond. The '63 did succeed in overcoming many of the '57's liabilities; nonetheless, many listeners today still prefer the tonal balance and immediacy of the original model.

QUAD produced both models simultaneously for a few years, ultimately ceasing production of the ESL-57 in 1985. Such are the capabilities of both speakers that new versions of both the '57 and '63 are still produced under license in Germany by QUAD Musikwiedergabe, a pair of which are listed for sale here. While certain technical and material deficiencies of the originals have been addressed, the "New Old" German models are said to faithfully adhere to the character and abilities of the original speakers.

QUAD continues today as part of the massive International Audio Group Ltd. (IAG), along with fellow veteran British brands Wharfedale, Leak, Castle and Mission. QUAD ESLs are made in China, these days, although R&D and design appear to still be in the U.K. It's remarkable how, given the far-flung locales of their production, the company still seems quintessentially British.

if you wish to learn more about Quad then check out the family tree in our Bluebook and be sure to search the Audiogon Forums for tons of info from experienced Quad owners.
audiogon_bill
I took off the dust covers as well as the grills. The dust covers, you know, cover the transducers, I never had an issue with longevity with the speakers and they were in use many years w/o the grills and dust covers. If dust is an issue in a room get air purifiers.
Ric Schultz said the same thing to me, twenty years ago. Now, at my age, with my time left, I may no longer need to be concerned with it ;-). Plus, now out of the damn desert, my dust situation is a thing of the past. I may just cut the darn things off!
bdp24
1,191 posts
05-18-2016 1:19am
"Ric Schultz said the same thing to me, twenty years ago. Now, at my age, with my time left, I may no longer need to be concerned with it ;-). Plus, now out of the damn desert, my dust situation is a thing of the past. I may just cut the darn things off!"

It just occurred to me I also removed the Quad 57 power supplies and placed them on outboard Isolators and replaced the Quad power cords (of course).
I've owned a lot of loudspeakers of all types, ported, sealed, front loaded horns, back loaded horns, etc. from a lot of the brands we chase after in this hobby.  I could go into the pros and cons of each, but will save folks the trouble.  Instead I'll simply say I still have few of the other speakers around, but I really only want to listen to the Quad ESL57s.

Sure, other loudspeakers play louder, lower, or whatever; we all have heard that again and again and again.  The Quads play louder than people think, as I normally listen at just under 95 dB at the listening chair.  While neither the bottom octave or blow you back bass are nowhere to be found, they produce high quality and enjoyable low frequencies.  People always talk about that midrange, the speed, or the imaging, and all of that is completely true.  But the things that the Quads get more right than any other loudspeaker, in my opinion, is the truth of tone and overall believability.  It's really not something you can measure or capture in a spec.  Like a lot of the finer things in life, it's the experience that sets them apart.  Once you encounter the Quads, other speakers just don't sound right.  Yes, other speakers make sound, but the Quads make music.

In all these years of chasing, the Quad ESL57 are the first and only speakers I've encountered that allow me simply sit down and enjoy the music.