Quads Unlimited Restored Quad ESLs
I have owned a pair of Quads Unlimited-restored Quad ESLs ("Quad 57s") for about a month now, and have listened to them for one to four hours daily in that time frame. To cut to the chase, in short, these are the best speakers I have ever had in my home, and in the areas most important to me they are equalled by few and perhaps exceeded by *no* speakers available at *any* price that I am aware of.
In the last seven years or so I've owned speakers such as Lamhorns, Beauhorns, Musical Affairs Sonatines, Tonian Labs TL-D1, Audio Note AN/Es, Zu Definition 2s, Acoustic Zen Adagios, a front horn/compression driver with bass reflex bass hybrid, Supravox field-coil drivers on open-baffle, Green Mountain C3s, Sonus Faber Cremonas, and more. At around $4500 with 14" raised stands (which are mandatory for getting the cleanest bass, I'm told), the Quads are far from the most expensive in that list, but I would take them over any of the above in a heartbeat. These speakers are completely amazing, and I really wish I had heard them years ago. I am done buying speakers now - for good, barring a future move to a room they just couldn't work in, which is very unlikely.
Here is what these speakers do so well:
- Speed and clarity. The speed and clarity they give sounds so much more natural to me than cone drivers, once one is acclimated, especially for unamplified acoustic music (all of my comments pertain mainly to acoustic jazz unless otherwise noted). They are simply faster & clearer than the fastest/lightest cones (and furthermore don't have the rising response issue of many of those fast cones, though many modern designs have beaten that). Of course, essentially all planars, especially electrostats, have this advantage. But they do not all have the other strengths of this speaker.
- Perfect timbre and harmonic density. Most, or possibly all, planar speakers I have heard, despite having the speed and clarity, have sounded something thin or missing body, which to me might be the #1 deal-breaker. Not these speakers - not at all.
- Perfect coherence: they sound like a point-source. I understand they are a two-way speaker; in my experience, well-done two-ways can sound just as coherent and seamless as the best single/wideband drivers. (Or even more so, with no cone breakups, whizzer anomalies, and their associated distortions?)
- Perfect transient fidelity. I have read that these speakers are so time & phase correct that they can essentially pass a square wave. There are no square waves in music, of course, but speakers that make time & phase accuracy a design goal have always had an edge to my ear. Transients are sharp and "leap out of the mix" just as they do with live music. This is a very important component to truly realistic sound!
Now to dissect the octaves in the Standard Way.
Bass - first of all, there is "more" bass than I was led to believe, both in extension and amplitude (relative to the rest of the spectrum). I have read *so many times* (more on this below) how Quads (meaning the original ESL) have "no bass, no treble, and no dynamics" - well, that is not true of THESE Quads, and I really can't stress that enough. My room is about 16x25 with a vaulted ceiling and a large opening. The speakers are along the short wall, about 3' from the wall, with the listening couch 9-10' from them. Bass extension is entirely adequate for all acoustic music and to me for rock too, although there is certainly a bit missing on the bottom. From my experience, and without measuring, I would say they are flat to 40-45 Hz with meaningful output substantially below that.
While the low bass is just a tiny bit bloomy, it's the midbass that really steals the show - and that's really what you need to really appreciate acoustic bass. The bass timing and pitch accuracy are second-to-none, making listening to Evans & LaFarro play off each other at the Vanguard or Minghus thump it in his soulful style the best I have ever heard it (Ok - with the limitations of audiophile memory taken into account). In fact, the speakers remind me of front-horns with field coil drivers in this respect (and they remind me of field-coil cones in other respects too - more on that below). Of course, dipole panel bass has the advantage of no cabinet resonances at all and less excitation of room nodes due to the cartoid dispersion. (I have read that original Quads could sometimes make the grills vibrate audibly - something Wayne's speakers NEVER do even when played quite loudly.)
The midrange - well, as always, the midrange is really going to make or break a speaker, and an audio system. And this midrange is *as good as it gets*. I mean, I think it is, literally, impossible, for a speaker to produce a midrange more pleasing and more natural, at any cost.
The midrange is utterly butter-smooth while also brimming with texture and nuance. My music listening is really all about bathing in *texture* while listening to jazz - those horns, and the way they are played, just have so much complexity and so much information. The midrange of the ESLs reminds me both of front horns and of my Supravox field-coil drivers, but perhaps combining the best traits of both. The front horns (B&C compression drivers in wooden conical horns) had incredible nuance and texture (and also of course incredible dynamics that the Quads can't really match). The Supravox drivers had the complete smoothness and also great texture, but not, I think, as good as the horns. And the ESLs do seem to combine the texture of the horns and the perfect smoothness of the field coil cones.
The treble never stands out because it is so seamless. You never find yourself thinking about "treble" while listening. (After all, there really isn't any such thing as a "treble instrument", is there? Cymbals may come close.) The speakers are just a touch on the dark side (and this is related to amplification - more below), but it is a very pleasant, very slight darkness, and nothing detracting substantially from reality. To me, the overall balance is perfect.
Time to talk about dynamics. Microdynamics, as should be evident from what's been written, are superb. Speakers that are as fast & clear as they come, and full of texture, make microdynamics evident. You hear everything. You hear loads and loads of musical information, and, yes, these things *are* important, in my opinion, to the musical experience.
But, of course, we know Quads seriously lack dynamics in the macrodynamic sense, right? Nope! Not these!
Of course they are not dynamic like front horns are. Nothing but front horns are dynamic like that. High-efficiency non-horn speakers with lot of midrange driver area can seemingly come close (Zu Definitions) to those as well. While the ESLs are not as dynamic as such speakers they are capable of quite impressive dynamic swings - they are capable of dynamics that can startle you! In fact, I think they are MORE dynamic than most conventional box speakers of typical sensitivity! Perhaps this is because there IS a lot of midrange radiation area. In short, I consider macrodynamics a relatively important area, and these speakers do not disappoint me.
Furthermore, the transient fidelity I discussed really contributes to the sense of dynamics. In all, I find the important aspect of dynamic shadings in acoustic music to be extremely well-preserved.
A note about the sensitivity (which is related to macrodynamics). I have read in the past sensitivity figures for the Quad ESL of anything from 82 to 86 dB/W. After I got the speakers, and found that my 15W Audiopax Stereo 88 could play them *loudly* without strain ("loud" to me is peaks of 92-95 dB, measured on the Rat Shack meter that is said to underreport peaks by 7-10 dB), I wrote Wayne Piquet (Wayne "is" Quads Unlimited) and said, basically, "there is no way these speakers are 82 or even 86 dB/W". He explained to me that while the original Quads out of the factory were about 84 dB/W (but with wide variations, even in two consecutive serial numbers) his speakers are *always* 88 or 89 dB/W. This is due to the much better tolerances and matching he uses in his rebuilds. Truly, these speakers must be better in every way than any brand-new Quad out of the factory in their heyday.
Up to now I've been talking mainly about acoustic jazz. Do they fare well on rock? I don't listen to much, but yes. Radiohead's "OK Computer" never sounded better! Neither did No Doubt's classic "Tragic Kingdom" (you'd better believe I'm serious), and I heard things I'd never heard before. And those backing horns were glorious.
I stopped, long ago, having virtually any interest in audiophile tricks. In that category I include imaging. Yet, if one cares to notice, these speakers image amazingly. I would imagine all planars are fairly good at this (my experience with planars is more limited than I would like, though I've heard various Maggies, Sound Labs, and new Quads at dealers and shows). I say that because of the fact that they're all essentially free of cabinet resonances. But, I do think these Quads do it better than most or all of the others. I would imagine that perfect time & phase coherence has something to do with this.
Though they are exceptionally revealing, at the same time they do seem to be a bit forgiving as well - and I realize that is a bit of a contradiction. I hear as much, or more, as on any other speakers I'm familiar with (I'm including some wideband-driver speakers that are exceptionally revealing), yet some less-than-perfect recordings are more tolerable than on many other speakers. One example: "Buena Vista Social Club". I'm not sure we could call this a *bad* recording, and the music is certainly exemplary, yet it has a bit of glare that is audible on almost all good systems - by the last track there is just no missing that glare, in my experience, and frankly I'm happy when it's over. (I'm talking about redbook CD; I don't have it on vinyl, if it's available.) On the Quads, the glare is on the lesser end of the objectionable artifacts scale.
I find the difference between vinyl and digital more noticeable on these speakers. Digital can still sound great, but they make me want to listen to vinyl as much as possible. (Yes, I realize I sound like I'm contradicting myself, asserting that the speakers are both exceptionally revealing but seem to give a bit of help to slightly harsh recordings. I don't fully get it either.)
Are there any weaknesses? Honestly, to me there are really none that matter. Of course the last octave of bass is missing. I can live with it on the few recordings on which it makes a difference. (And this makes the speakers more family-friendly, as the dipole bass does as well, which is very important to me as my system is out in the living room and always will be.) While it's true that the vertical dispersion is somewhat narrow, the horizontal dispersion is *not*. I've heard comments like "you have to keep your head in a one-foot square" - that's nonsense. Only 10' back from the speakers the sweet spot on the couch is easily three-wide.
And, again, they don't have the dynamics of front horns - of course. (Another thing that makes them family-friendly - and while I'm on that subject these are the very best speakers for low-level listening I've ever heard.)
Then there's that other Quad myth - can't play "loudly". I can play them, again, to 95 dB at the listening seat, which is likely peaks more like 100 dB, and they are clear as a bell at that volume. I haven't pushed them farther than that because that's 5-10 dB louder than I care to listen anyway. Of course, "loud" is relative. (All Wayne's speakers have the tweeter clamp boards; you can't damage them.)
And I can do that with a 20 watt OTL tube amp! What a plus that is. Everyone knows that the truly best-sounding amps, unless you spend really crazy money (and maybe even then), are the low-wattage ones.
The next time you hear or see someone refer to Quad ESLs as having no bass, or no treble, or no dynamics, you can rest assured that they're either repeating what they've heard elsewhere or are speaking of the *broken*, worn-out ancient Quads they've heard. And that's that. At a bit over $4K, these speakers are an absolute, drop-dead bargain. I cannot think of another speaker under $20,000 I would rather have, although I never got to hear the big Tonian with the 12" PHY driver and it's been some time since I've heard the big Sound Labs. (Surely the big Sound Labs have deeper bass and higher SPL capabilities, but I'm still not sure I'd take them. In fact, I rather doubt that I would, and the fact that they need massive amps to sound good is part of the reason for that. But, admittedly, my experience is neither recent nor extensive enough to have any definitive conclusion on that score.)
Digital: Audio Note Kits DAC 3.1 fed by Mac Mini
Analog: Basis Ovation/TriPlanar V Arm/Various cartridges, Tom Evans Microgroove+X phono
Line: Tom Evans Vibe/Pulse
Amps: Audiopax Stereo 88, Graaf GM20
A note about amplification. People familiar with the Quads are aware of their wild impedance curve, going all the way to 35 ohms or so in the bass and down to 1 ohm in the treble. This means that a powerful voltage-source solid-state amplifier that puts 100W into 8 ohms like likely be able to do no more than 25 or less into the bass range of the Quad! And it means that transformer-coupled tube amps and - even more so - OTL tube amps have a large advantage here. My Audiopax and Graaf amps are both just excellent on this speaker. I give the Graaf the nudge but it's a matter of taste - the Graaf is just a bit more neutral, while the Audiopax is a bit more meaty (and I think just a hair smoother too). These amps are rated at 15 and 20 watts, respectively - and they are plenty of power, IMO, for these (more sensitive) rebuilt Quads.