Small Wonders

by Roy Gregory | December 16, 2011

ritain has a long history with -- and a proven fascination for -- small loudspeakers. "Quart in a pint pot" is a phrase that could have been coined to sum up what amounts to a national obsession with trying to get the biggest bass and most defined soundstage from the smallest possible box. Further, and in typically xenophobic style, we always tended to assume that not only was this our obsession, but that nobody else could or should share it. Fortunately, none of our near neighbors paid any attention, and having observed a market opportunity, they busily beavered away in response. The rest, as they say, is history.

It might have started with the Goodmans Maxim, but it kicked off in earnest with the LS3/5a, a BBC design intended for the location monitoring of spoken program in outside broadcast trucks. The inside of what amounts to a motorized caravan (or RV in current parlance) gets pretty full pretty quickly once you start installing a complete broadcast studio, so space was at a premium, resulting in a loudspeaker design about the same size as a Jimmy Choo shoebox -- diminutive dimensions that never seemed to discourage audiophiles from using them to reproduce the full orchestral repertoire! Despite the enthusiasm with which it was pursued (or, in some cases, because of that enthusiasm), it was an endeavor that was doomed to failure -- most often foretold in the death rattle of a B110 bass/mid driver hitting its end stops. And if that didn’t do it for the speaker, then the 15-ohm load presented to those early solid-state amps caused them to outrun their power supplies all too quickly, driving them into clipping and sending the T27 tweeters on a one-way trip to the audio hereafter.

I for one never actually understood the fascination with the LS3/5a -- or the equally limited Quad ESL for that matter. No matter how well these speakers could work across a limited bandwidth and dynamic range, as far as I’m concerned high-fidelity reproduction has always meant having at least a decent stab at representing something approaching a realistic sense of scale and musical impact. But that didn’t stop a dedicated cadre of designers from pursuing the small-box solution. First came the Linn Kann, a speaker that tried to overcome the LS3/5a’s dynamic limitations by simply dispensing with any semblance of flat frequency extremes. But the real breakthrough product was the Celestion SL6. Twice the size of a '3/5a and with a 6 1/2" bass driver coupled to the first serious metal-dome tweeter, it delivered something approaching the sort of bass weight and scale that real systems should have, albeit at the expense of severe dynamic limitations.

It wasn’t until people stuck bigger and bigger -- and then even bigger -- amplifiers on them (this was the heyday of the Krell monoblock) as well as building a lighter, stiffer and far more expensive cabinet dubbed the SL600 that it dawned on us all that the problem wasn’t cripplingly low sensitivity -- which was actually about the same as the LS3/5a’s -- but horribly sluggish drive units that simply sapped energy. The newly fashionable laser interferometry (see those drive units move in real time!) might have produced drivers free of in-band break-up modes, but it failed to point out why that was. It’s pretty hard to make a mattress enter a resonance mode, but that doesn’t mean we should make drive units out of it. The original SL6 cabinet certainly contributed to the thick and sluggish bass, but even the Aerolam-sandwich-version couldn’t overcome those lossy, turgid drivers.

Arguably, we’re still recovering from the popularity of the SL6 -- and the blind alley of audio development it turned us down. Harsh? I don’t think so. Without the SL6 we wouldn’t have had a decade of dreadful metal-dome tweeters forced down our throats, followed by a backlash that dismissed any form of metal or ceramic material, no matter how promising the results. We also wouldn’t have had such widespread acceptance of the belief that suddenly it was okay to foist the sole responsibility for system dynamics onto the amplifier. The SL6 opened the door to a decade of low-efficiency, flat-frequency-response loudspeaker designs that led to systems that were so well behaved that they completely missed the point. It’s children that are supposed to be seen and not heard -- not hi-fi systems; but when systems sound this polite and dynamically constricted, it’s no wonder that listeners lose interest.

The next homegrown pretender to the small-speaker throne was Acoustic Energy’s AE1. Somewhat more dynamic and extended than the SL6, although even smaller, this promised to solve the dynamic issues, but ultimately the all-aluminum drivers failed to deliver -- although they did form excellent heatsinks, meaning that you needed to go some to overdrive an AE1. End result: ever-bigger amplifiers trying to squeeze even more sound from another tiny box.

The outer fringe

Two other small speaker designs stand out as worthy of mention, partly for their excellence, but also for their individuality. The Spica TC50 was a US design that nevertheless achieved a passing popularity in Europe and the UK. Its unusual triangular-section cabinet, basic drivers and felt-covered baffle did little to endear it to potential customers, but boy could it image, and as with a lot of speakers for which that’s true, it exhibited considerable rhythmic articulation and coherence too. With a premature roll-off in the highs, as well as limited power handling, this design was even more about the midband than most others -- but it really was a glorious midband. The Spica tragedy was that it never developed into something bigger or better, but simply faded away.

Our other quiet contender is the ProAc Tablette, a genuine miniature of elegant proportions and surprising musical accomplishments. It established the slim-but-deep cabinet proportions that soon became de rigeur, whilst delivering an astonishingly subtle and sophisticated musical performance. In many ways a significantly better-balanced overall performer than the LS3/5a, the Tablette suffered for the reticence of its manufacturer, who was unwilling to shout its virtues from the rooftops in the fashion of certain competing products. Even more ironic is the fact that it enjoyed a spiritual cousin in the shape of Audioplan’s extremely similar Kontrapunkt, a speaker that suffered exactly the same malaise.

But perhaps the Tablette got the last laugh after all: with so many pretenders come and gone, the little ProAc is still in production. Now in its ninth iteration and still recognizably the same product, it continues to provide understated yet unfailingly musical results despite its diminutive dimensions.

-Roy Gregory

By now you might well be wondering why anybody bothered with what was apparently a hopeless task. Well, that’s partly down to a limited frame of reference: compare one small speaker with another small speaker and one will be pronounced "better." Compare that "winner" to a large full-range loudspeaker with higher sensitivity and greater dynamic capability and its shortcomings will be all too apparent. The problem was that nobody did -- partly because of the audio obsession with comparing like with like, but mainly because most simply couldn’t accommodate the larger speakers. That’s the real driver behind this story: the fact that UK homes have smaller rooms and fewer of them than houses in the US. Add to that the predominantly brick construction of UK housing, a feature that adds a useful measure of bass reinforcement (in stark contrast to the drywall midbass absorbency of most US homes) and you can begin to see how a small speaker might flatter to deceive -- and why a listener might be all too willing to give it the benefit of the doubt. In any house where the listening room is also the lounge, you’d better believe that when it comes to speakers, size matters!

But it’s not only the UK that suffers from small rooms and limited accommodation. It’s a Europe-wide phenomenon, and as I hinted earlier, it was the Europeans who made the first serious steps towards a solution of this particular problem. Sonus Faber first hit the UK’s shores with the Electa, a compact two-way speaker with a 6" bass driver and a solid-wood cabinet. But the model that really changed the game was the next one up, the Electa Amator. This used a mass-loaded, paper-cone woofer -- heavy but stiff -- and finally, with enough sheer grunt injected up its fundament, the results were spectacular. The combination of the Elector Amator and the Audio Research M300 monos was justifiably legendary, the scale and weight generated from this compact pair of two-way loudspeakers truly astonishing.

There was more at work here than just the big-amp/small-speaker thing: the combination of the Esotar tweeter (a term I use loosely -- at least as far as extension goes) and the hard, white transparency of the first-generation ARC hybrid amps was, if not exactly a case of two wrongs making a right, definitely in the category of the whole being greater than the sum of the parts. In fact, I’d go even further and categorize it as a guilty pleasure: you know it’s wrong but somehow you just can’t help yourself.

This Sonus Faber marked the realization that the one thing you can’t afford to lose from a small speaker -- indeed, the one thing they can actually do quite brilliantly if allowed -- is a coherent sense of musical dynamics. It’s not a lesson learnt by the entire range, or the product category as a whole, but since the advent of the Electa Amator, the game has definitely changed. Nowadays, small speakers are all about delivering open, expressive dynamics with just enough bass to underpin them convincingly. It’s a careful balancing act, but done well the results can be quite remarkable. Successful examples include the original Totem, the B&W CM1, the Focal Micro Utopia (and now the Diablo), the Sonus Faber Cremona Auditor M and the Wilson Duette. It’s ironic that, given the departure point for this piece, on this list, only the B&W (and its derivatives) are a British design. But then the list is far from exhaustive, and a recent addition would certainly be Spendor’s SA1, a brilliant small speaker that shares its name with an earlier model, a contemporary of and rather more convincing alternative to (to these ears at least) the original LS3/5a.

Of course, none of this would be worth bothering about if speaker designers hadn’t made some significant progress, and while I’m not sure they’ve finally cracked it -- or even if "it" can be cracked -- the latest entries in the stand-mount speaker market offer a far more balanced musical perspective while retaining and extending the traditional virtues. When you start with a small box, it presents some pretty severe challenges -- but it offers opportunities too. That small volume will inevitably impact bass extension and system sensitivity, but the small panels are inherently stiff, the small drivers have good dispersion and the small front baffle helps that even more. What’s more, the lack of deep bass also means the absence of the problems that occur when it’s there -- so you should find timing, articulation and midband clarity far easier to come by from such a small cabinet. There are other benefits too: the two-way crossover might suggest a ticklish transition point, right in the upper midrange, but it also generally means fewer, physically smaller components -- both of which are good things. Finally, there’s the whole question of a stand to go with the speaker. Whilst there’s no doubting that the wrong stand can kill a speaker’s performance, the opportunity to control or at least distance the interface between the cabinet and the floor is a potentially massive advantage, especially when it comes to dissipating all the energy from that small, stiff enclosure.

Roll all those things together and it should be a recipe for an articulate and spatially precise performer capable of delivering real clarity and musical insight -- if the designer can get the balancing act spot on. That means that the designer needs to deliver enough bass to satisfy without crippling the speaker’s efficiency or drive characteristic. That bass needs to be agile enough to time, weighty enough to fool the listener into thinking the speaker is bigger than it is, but not so loaded that it muddles or slurs the midrange. The top end must also be balanced against the bass or it will end up sounding bright and exposed. Tonal warmth and harmonic weight must be balanced against clarity and transparency, resolution and detail against body and presence.

All in all it’s the audio equivalent of walking a tightrope across the Grand Canyon in a savagely gusting crosswind -- with about as much margin for error. There’s a considerable performance gap between the really great small speakers and the also-rans, and those that fail to make the mark are at best inoffensive and at worst they crash and burn.

Why this rambling dissertation on the history, appeal and the UK/Euro flaws-and-all fascination with small speakers? And why now? Because the latest wave of two-way stand-mounts has just washed up upon the doorstep of my listening room. From Crystal Cable in Holland we have the Arabesque Mini, the compact follow-up to the astonishing glass floorstander; from Raidho in Denmark we have the Ayra C1.1, a speaker design that takes the term "in-house" to new levels of obsession; from Audioplan in Germany we have the Kantata, a distinctly different design to its predecessor, the highly regarded Kontrapunkt; also from Germany comes the elegant Lindemann BL10. Factor in the aforementioned Spendor SA1 and Focal Diablo, the current incumbents, as well as throw in a few other contenders that are bubbling under.

It looks like it’s going to be a small-speaker winter-into-spring. Let the fun and games commence.

The Audio Beat • Nothing on this site may be reprinted or reused without permission.