AudioKinesis Swarm Subwoofer System

Getting The Bottom End Right

Equipment report
Audiokinesis Swarm Subwoofer System
AudioKinesis Swarm Subwoofer System

One of the fundamental problems of audio, arguably the fundamental problem, is how to reproduce lower frequencies correctly—frequencies which are down in the region where the room affects them in really major ways. The Swarm System from AudioKinesis represents a new departure in subwoofer systems, and to say it works well is an understatement. It is completely stunning. To my mind, it is a revolutionary development in subwoofer design. 

Small-room acoustics are a tricky subject, and become even trickier when one begins to worry, as one must, not just about how things behave physically in the room but about how they are actually heard. Acoustical analysis carries one only so far. Still, both theory and listening practice have come together with the idea that having multiple subwoofers placed at asymmetric locations around the room is desirable for producing the listening experience of smooth, uniform, and precise bass. Earl Geddes has been a strong advocate of this idea, and it is also presented in a favorable light in Floyd Toole’s book on speakers and rooms. But for some reason, audiophiles have been reluctant to pursue this with full vigor.

Now Duke LeJeune, the moving spirit—owner and designer—of AudioKinesis, who has long been a follower of Geddes’ theoretical work, has produced a system intended to make this multiple-woofer idea a reality—conveniently, effectively, and not too expensively. The system itself is relatively simple in its electrical nature—all four woofers can be driven by a single amplifier, with series/parallel connection taking care of impedance issues. (Series doubles impedance, parallel halves it, so four can be connected to have the impedance behavior of one.) Alternatively, one can use two AudioKinesis amplifiers, which makes the adjustment of the phases of one pair of subs versus the other pair possible, in addition to stereo operation.

The secret is the placement! The four subs, when driven by a single amplifier, all have the same intrinsic output, but they can be placed at different positions, and in principle this can result in an acoustic loading and room interaction that will produce more even output over the room as a whole than would be possible with one or two woofers.

Put in broad terms, in different locations, each driver will excite the room modes in somewhat different ways, so that the combined effect will be smoother throughout the room as a whole than that of an individual subwoofer. A single sub can of course be DSP EQ’d to produce smooth flat response at one position, but typically this will involve rather irregular response elsewhere in the room. (This is the effect that Lyngdorf Audio’s RoomPerfect DSP correction system deals with—seeking the best compromise between flat at the listening position and smooth over the room as a whole. But naturally it is better if the difference between the listening position and other positions is minimized—which is what a multiple subwoofer system is intended to do.)

Now ideally one would begin adjusting the gain of each of the multiple woofers separately. But in practice, adjusting their locations with identical drive to each woofer already gives one an excellent result, with adjustment applied only to the overall drive level if need be. (And the two-amplifier setup with stereo sound and independent phase adjustments on each sub is even better.)

How It Worked In Practice
It will no doubt be somewhat disconcerting to the makers of large monolithic subwoofers to report the truth here: The Swarm, in fact, worked better than one or two subwoofers, even when those were DSP-adjusted. The effect could itself no doubt have been pushed further along the road to perfection via DSP correction itself or with even more subs. And optimal results depended on some experimenting with position. But even a relatively simple sort of randomization and an adjustment of overall levels gave surprisingly convincing results—by any standards of bass performance in rooms. (The bass amplifier supplied allows a single parametric EQ as needed, usually to eliminate the floor-to-ceiling boom.) The amplifier can also be used to provide a high-pass crossover to the main speakers if desired. I mostly worked with the main speakers running full-range. (I tried PSB Alpha B1s, Infinity P363s, and Stirling Broadcast LS3/6s.)

This idea of multiple woofers giving multiple drive points for bass really did strike me as the way to go in practice. I think this is the future of bass in rooms. Period. In the practical world, I think there won’t be any doubt in your mind, once you have heard the Swarm system, that for the true seeker of ideal bass, multiple woofers are the way to go.

What It Sounds Like More Specifically
Bass in small rooms compared to bass in concert halls and other live music venues typically lacks power or definition or both. Turn the level up, and the bass booms and sounds ill-defined. Turn the level down, and the bass lacks power—and usually still continues to lack definition. The Swarm makes bass that has both power and definition. Go to an orchestral concert and you will get the idea. Power galore but definition and precision, too. Precise bass attacks—and precise stopping of the sound and differentiation of the ring of the hall versus the sound of the instruments themselves. We all know what it sounds like. But we seldom hear it at home.

Wall-mounted speakers like the Allison Model 3s and the Larsen Model 8s get one closer to life than typical free-space floorstanders. So do the DSP’d corner woofers of things like the Steinway Lyngdorf S System. But the Swarm gets one closer still. One can do mathematics on how this works, and on how even frequency response is attached to clean buildup and decay. But a listen is worth a lot of formulae.

The definition aspect is more than a matter of “tight bass” in the audiophile sense. At the risk of using a phrase that has been used in suspect ways in the past, the Swarm system plays bass tunes exceptionally well. One can really follow bass lines in orchestral music in a way that escapes most systems completely. This is how live bass sounds. One has no doubt what the bass viols and the trombones are up to in real life. Here, one has that same sense of transparency in the bass but without sacrificing any of the bass power.

On large-scaled music, this really redefines one’s listening experience. It is not just that the balance of the bass is natural. The clarity of it combined with its natural level gets one very close to the live experience of bass in large halls. The whole orientation of the music changes. Large music is no longer melody on top, with some harmony in the lower mids and either murk or weakness further down. The music shifts around to be built, as it should be, on a firm foundation—from the bottom up, with the bottom unexaggerated but absolutely present to the extent it should be, and resolved completely.

The Spatial Effect
There is more to what is going on here than just the perception of what is happening in the music itself. There is also a quite startling spatial effect. We are all accustomed to being able to control room effects in the mid and higher frequencies by acoustical treatment. But this is harder to do in the bass, and in most rooms there is a definite residue of spatial signature carried in the lower frequencies. The bass is one of the main ways you sense the size and shape of the room around you, and typically the signature of the recording venue is overlaid or even swamped by the bass signature of the listening room.

But the Swarm, presumably because of its smoothing out of response, largely suppresses the bass signature of your listening room. And as a result one can hear the original venue in a most unusual way. I played in a performance of the Sibelius Second Symphony recently, so I was particularly attuned to the acoustic effect this piece makes in a concert hall. Listening to Berglund’s recording for EMI with the Swarm in action, I heard a remarkable facsimile of the size and envelopment of the actual symphonic sound emerge. At the end, I felt like standing up and cheering, so close did I feel at some basic level to the real experience.

Now any addition of full-range bass gives some of this effect. But the Swarm gives more of it. Not more bass than other subs—lots of them can be turned up to give plenty. Rather, there is better bass with less signature from the listening room.

Adding a second amplifier to drive two of the four subs separately and thus to be able to adjust their gain and phase independently gives potential for even better results. Dave Griesinger has suggested that putting two subs (or sets of subs) on either side of the listener and running them “in quadrature”—90 degrees out of phase—will produce additional spaciousness, and this seems to work extremely well, enhancing the basic Swarm sound.

This whole spatial effect is not an easy matter to convey in words. But it is easy to hear, striking indeed, and very satisfying. If you are interested in the reproduction of large-scaled music, the Swarm will offer new dimensions—almost literally—to your audio experience.

The Product As A Product
This is a system that works. Truth to tell, it seems to me to make even the most magnificent of one-point subwoofers into dinosaurs, something grandly impressive in their time, but their time is over.

And, of course, it is a great advantage that many woofers are used, as no single one of them has to produce all that much sound. Lower distortion is right there to be had. And lower price as well, since it is no longer necessary to try to make all the bass power come out of one item that, at the same time, has to be rational in size (usually). A lot of little subs are easier to make than one big one—plus they work better.

Now the idea of using a number of subwoofers could be easily duplicated. Just buy a lot of subs and wire things up right. But the Swarm is such an excellent manifestation of the general idea and at such a reasonable price that one is hardly tempted to do anything except just purchase it. These are low-distortion subs, and they are well-adjusted in their roll-off in the extreme bottom to match room-gain effects. Moreover, the amplifier supplied works very well, with lots of power and just the right adjustments. The amplifier is inexpensive, but it does the job. And as noted above, it is actually worthwhile to add a second amplifier to get the extra flexibility of independent phase adjustment. The whole system is so easy to set up, so well thought out, and so modest in price it would seem not very sensible to try to cobble together something to do the same job in a jury-rigged, do-it-yourself way. The Swarm even has domestically compatible looks. The subs can double for end tables. (Paige said it was all right to leave them in the living room: You can’t ask for more than that.)

The Overall Significance
Once asked to comment on his competitor Gluck, Handel said: “My cook can write a better bass line than Christopher Willibald Gluck.” (This was, as it happens, literally possible—Handel’s cook was a professional musician as well as a cook.) This famous witticism conceals a profound truth. Handel felt that a strong bass line was a fundamental part of musical counterpoint—that music should not just be heard from the top down but also from the bottom up.

It is believed indeed that Handel often wrote his bass lines first and added his famous melodies on top as counterpoint. I don’t suppose Handel ever gave much thought to subwoofer systems. But if he were around today, I think the Swarm would be his unhesitating choice.

Audiophiles tend to be very concerned about the upper half of the musical spectrum. “Female vocals” are the standard test material for many. Perhaps this arises precisely because it is the upper-frequency material that does not change so much from one room to another. So, if one thinks of audio as mainly about a system of equipment rather than about the combination of that system and a room (as is really the case), then it becomes natural to concentrate on the part that is affected least by the room.

Unfortunately for this view, the lower frequencies are a truly vital part of music. They are harder to deal with in a domestic environment than are the upper reaches, but deal with them one must. The Swarm seems to me to be the way to go. It really does a remarkable job of taking the room out of the sound in the lower frequencies, where that is so hard to do.

I suppose one get even better results with two Swarms, or three, or…the mind boggles. But one Swarm is already a new world of bass excellence. Hearing is believing.

This is one that works.


Type: Multiple subwoofer system, four subwoofers, series/parallel connection to 1000W subwoofer amplifier (included)
Drivers: One 10"4 long-throw driver per sub; vented enclosure for correct roll-off to compensate for room gain (ports can be plugged with supplied plugs, if desired)
Frequency response: 20–100Hz (typical in-room)
Adjustments: Upper-frequency limit, phase, gain, and one-frequency parametric EQ
Dimensions: 12" x 23" x 12" (each subwoofer)
Weight: 44 lbs. each
Finishes: Oak, maple, or walnut
Price: $2500 plus shipping (sold direct)

Duke LeJeune
Dallas, Texas
(504) 251-2311

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