Quad ESL-63 loudspeaker Page 2

Incidentally, Quad's instruction booklet for the 34 preamplifier makes a very good point about listening level, asserting that for a given recording there is only one correct volume setting. I agree generally, but with qualifications. The "correct" setting is where the perceived volume of the instruments "agrees" with their apparent distance from the listener, which makes perfect sense when the recording was done with "purist" microphone technique—two, or at most three, microphones for pickup of the entire group.

But many multimiked recordings produce an ambiguous perspective, where instruments sound very close yet far away (London is a past master of this so-called near-far sound), and for these the "correct" volume setting is far less preordained. In either case, proper volume adjustment requires a certain familiarity with the sound of the real thing, which is something audiophiles as a group cannot always bring to a listening session. Some recordings, such as the ones Harry James has done for Sheffield Lab, demand very high playback levels in order to sound realistic; for these kinds of recordings, the Quad '63s are simply not appropriate.

Many audiophiles like to play all recordings at very high level, sometimes because the loudspeakers are "slow" and seem to prevent the sound form escaping from them, sometimes simply out of a wild and crazy desire to feel the music (footnote 3). And hard-rock enthusiasts are notorious for playing their systems at ear-shattering levels for no better reason than Because.

The Quads are not designed for that kind of abuse, and although they may not be damaged by it (unless continued for some time), they just won't deliver that much SPL. They are designed primarily for the classical-music listener who intends to listen at volumes one would encounter in a typical (perhaps even distant) concert-hall seat.

Those readers who are familiar with the startling aliveness of the original Quad Electrostatics are going to be very surprised by the '63s, and not necessarily in a pleasant way. They are far smoother and more extended at the high end, but while the originals were somewhat bright and forward-sounding, the '63s are by comparison warm, withdrawn and almost overly rich.

The '63's low end extends to just a bit below 40Hz (see fig.1) and the quality of that bass is superb. It is tight, detailed, as solid as oak, and (with the right room location) excellently balanced against the upper part of the range. There is a problem, however. As we listened to a number of dynamic recordings in an attempt to locate just where the '63s would shut down, or sound threatened, it was always on low-frequency notes such as bass drum or kickdrum that problems were encountered.

For this reason we recommend subwoofers for those who listen to music with a lot of impactive low frequencies, or for those who wish to listen to wide range symphonic music at true concert-hall levels. Unfortunately we do not know of a subwoofer that is as psychoacoustically "fast" as the Quad's low end and would thus blend with it. (It would be almost impossible for a dynamic woofer of any size to be literally as fast as the Quad diaphragms.)

One recommendation could be made from the Chicago CES, with the reservation that we have not spent time with the product: the RH Labs subwoofer, made in Portland, Oregon. A pair of these were teamed up with the Quads in the Electrocompaniet room and the result was dynamically more satisfying than the Quads by themselves.

In short, I was impressed with some of the things I heard from the 63s, but less impressed with their accuracy. Their persistent dryness and slight top-end tizz led me to suspect that they might sound exceedingly good with the right tubed amplifier. At the time of this writing the only such amplifier which has worked well is the EAR 509 reviewed in Vol.6 No.3. Catch 22: I was able to spend only two hours with that combination before the amplifier had to be shipped back to the distributor. We have the promise of a further loan and will report on the results of that and any other successful combinations as soon as we've spent enough time with them.

Addendum to the Foregoing: After this review was written, the second speaker of the first pair of ESL-63s I received started arcing over on loud passages. Now, one failure out of two speakers can be bad luck. But two breakdowns out of two is rather pushing the laws of chance, and would seem to indicate a real problem.

Our first suspicion was quality control at Acoustical Manufacturing, but Quad USA was surprised to hear of our having any problem, and in fact we have not heard of problems from consumers—which we would have if the failure rate was 50%! Sure enough, when we talked to our friend Alan Hill of Plasmatronics about our experience, he confirmed that the low atmospheric, pressure, low air density, and extreme lack of humidity present at 7000 feet (remember we're doing this testing in Santa Fe, New Mexico) could bring about significant problems with arcing.

Our second sample pair hasn't had the arcing problem but we've also been fairly cautious in our playing of them—it doesn't help our reputation with manufacturers when two pairs of speakers in a row fail, regardless of the reason.

Unfortunately, we still do not have a satisfactory explanation of the low SPL availability of the 63s. In repeated tests we get maximum levels in the 88dB range, which simply isn't enough. This has been true with both high and low powered amplifiers, tubed and solid-state—and of very high quality. Another as yet unsolved mystery, on which we will be sure to report in the future. In the meantime we recommend a careful audition of the Quads prior to purchase. If they meet your loudness requirements, that's all that really matters.

Footnote 3: JGH himself is not totally immune to this temptation—Larry Archibald

Echolane's picture

I imported my Quad ESL-63 from a London store in summer 1985 after reading a glowing review of them in Opera News. They were considered the ideal speakers for opera and classical. Unfortunately, they were unaffordable at their US price point. Luckily, I discovered they were less than half that in England, even adding in transportation and a small import duty and I have been enjoying their lovely sound ever since. I often joke that I will be buried with them, they are that wonderful for the kind of music I like, opera and classical. I snapped up a pair of US Monitors in 2023 that had just been restored to like new which should keep me happy the rest of my life.

While it’s true that they do not produce a lot of bass I’ve never missed it. But a friend loaned me a subwoofer and I’ve decided to keep it. I have it turned to barely there and am quite happy with it set to barely there. Without the need for a crossover, the sound is seamless, the midrange and highs are exquisite. I have to add that it is also fun to own them because they tend to fascinate my visitors.