Review: Audiokinesis Planetarium Beta Speaker

Category: Speakers

As of this writing, I have owned the Audiokinesis Planetarium Betas for just over two months. They did take a bit of time to break in, complicated by the fact that I’m driving them with a new amp (Atma-Sphere S-30 Mk III, with which they were designed), which took even longer to break in. I feel as though I’m finally qualified to write some reasonable commentary.

First, a bit of history. The Planetarium Betas replaced one of the best speakers on the market, the SoundLabs A-1PX. I hardly need explain that this was a very difficult act to follow. Interestingly, Duke Lejeune, who owns Audiokinesis and designed the Planetarium Betas, is a long time SoundLab dealer. Duke makes no secret of the fact that the Planetariums were designed to mimic specific characteristics (in particular, radiation pattern) of the big ‘stats. Since the soundfield was – and is – one of the things that I so admired about the SoundLabs, Duke’s design seemed like a logical place to start.

The Planetarium Betas are most definitely not your typical box speakers. They employ what are, in my opinion, several innovative and extremely well-designed features that propel the overall system far beyond the sum of its parts. The main speakers are large, heavy, oak-veneered cabinets with a 12” woofer and a 1” compression, waveguide-loaded on each of the front and back (i.e. a bipole configuration). The idea, as I understand it, was to open up the soundfield while tightly controlling directionality. More on that later. The woofers are deliberately designed to roll off below 60-65 Hz, where the subwoofer system takes over. The mains are placed approximately 7 feet from the front wall and 2.5 feet from the side walls. Do not, under any circumstances, place these things in a room with insufficient space behind them. As a test, I moved them to with 2 feet of the front wall. The magic went poof in a hurry. Personally, after playing with placement over these 2 months, I would allow an absolute minimum of 4-5 feet behind them.

Perhaps the most novel bit of the Planetarium Beta is the SWARM subwoofer system, consisting of four comparatively small, oak-veneered cabinets, each containing a long-throw 8” woofer and a port on the underside of the unit. These are driven by a supplied 1000w amp. I assume that this amp runs in Class D, although I don’t think that it’s actually mentioned as such. It remains completely cool after hours of use. There are front panel controls for crossover frequency, gain, and phase. The amp must be connected to either a second preamp output (if available) or to a line level adaptor that is attached to your main amp speaker outputs. Duke supplies the latter if required. I’ll describe the sound in more detail directly, but let me address the style and space issues first. There will, no doubt, be those for whom the presence of four boxes (small though they are), with attending wiring, is a deal-killer. The further need for those boxes to be scattered asymmetrically from wall boundaries may cause even more to say ‘no way can I live with that’. For the rest, I can tell you here and now that you would be rewarded with some of the finest bass, both in terms of quality and quantity, that you’ve ever heard. The theory is that positioning the individual subs at substantially different distances from room boundaries will cause the inevitable nodes to cancel each other out to a large degree. In geophysics, we call that phenomenon destructive interference, and it’s not usually a desirable thing. It is, however, quite advantageous in the world of room acoustics. In short, the SWARM works, and extremely well at that. Oh, and by the way, Duke sells the SWARM as a separate system. I would love to hear it with a pair of Quads.

So, on to the sound. I have owned many speakers over the decades, nearly all dipoles of one sort or another. I find that these create a natural soundfield that, all else being more or less equal, just sounds more like real music in real spaces. The best of these, up to the Planetarium Betas, has been the SoundLab A-1PX, which created a beautiful sense of 3D space laterally, vertically, and in depth. As I said previously, Duke used the soundstage from these speakers as his notional goal. I would say that, with a few minor adjustments, he has succeeded beautifully. In fact, the Planetarium Betas are somewhat superior to the SoundLabs in a couple of areas, namely depth of field and apparent extension beyond the physical edges of the speakers (i.e. width). These are both highly dependant on source material, of course.

A few weeks back, a couple of audio buddies visited and spent a few hours listening to the new goodies. The amp wasn’t really broken in yet, having only 20 hours or so on it. And the Planetariums have improved in the interim as well, although less spectacularly. Apart from some very nice complements about the overall sound, they had a couple of suggestions. The first was that they thought the subs needed to be moved around a bit more for fine tuning the room response. They were right, but that was an ongoing process anyway. What they absolutely nailed was the relative shortening of height compared to the SoundLabs, and indeed to their own speakers (both own Innersound Eros). I had been too caught up with playing with other things to realize that this was much of a factor. I ended up 1) moving my listening position forward about a foot, and 2) placing the main speakers on a pair of 4” lyptus wood stands that I had been using for my previous monoblock amps. The difference was absolutely amazing. Changing the relative angle between the listening position and the speakers by a few degrees resulted in a major improvement in apparent height.

With that change, I find the Planetarium Betas unequalled in my experience when it comes to soundstaging. One of the standard LPs that I use for soundstage placement and imaging is the 45 rpm single of Louis Armstrong’s St. James Infirmary. Not only are the individual players in what I imagine their proper locations to be, but the sense of real artists playing 3D instruments is astonishing.

OK, so the soundstaging is all for naught if the speakers are out of balance, have major dips/peaks in the response, etc., etc., right? Well, in general I find them to be extremely well balanced, as long as one restrains one’s heavy hand with the bass amp’s gain control. The tweeter is a first in my experience. I’ve used almost nothing but ‘stats (with a ribbon thrown in) for many, many years. The compression tweeter and its integral waveguide are what I was most worried about. That anxiety was unfounded. Highs are extended and sweet, lacking just a touch of transparency in comparison to the SoundLabs (big surprise). Cymbals are reproduced exceptionally well, with a proper bite but no trace of ‘sizzle’. Actually, I’m not sure of the crossover frequency (maybe Duke can shed some light on this?), but it’s clear that the driver is covering quite a wide range. One of my best recordings, Art Pepper’s Plus Eleven, can sound quite unbalanced with inaccurate speakers. With the Planetarium Betas, all is well, with Pepper’s sax sounding as good as I’ve ever heard it. Oh, and the imaging on this great LP!

I think – and it’s only a suspicion – that there’s a broad, very shallow dip in the response from perhaps 1000-2000 (?) Hz. It is in no way unpleasant, and is quite subtle. I would suspect that it contributes to the sense of depth.

The woofers are lightweight 12” pro units, and display a transient response that is unexpectedly excellent. I would speculate that the lack of necessity to handle the deepest bass may have allowed Duke to pick drivers for their ‘fast’ characteristics. In any event, these large units blend seamlessly with the tweeters. My standard test for driver integration is Edgar Meyer’s Zigeunerweisen on Uncommon Ritual. Meyer uses the entire range of his double bass on this cut, and if there are discontinuities of any sort, it shows them up clearly. Perhaps more than any of my ‘test’ recordings, Zigeunerweisen showed that even some aspects of timbre reproduction are, in fact, superior to that of the SoundLabs. The double bass simply sounds more organic, more ‘there’.

Orchestral music is an absolute joy on the Planetariums. Instruments are faithfully reproduced and in their proper places (there’s that soundstage factor again). One of the best recordings of a small orchestra that I own is Britten’s Young Person’s Guide to the Orchestra (on Cisco LP). The music itself was never intended to be the ultimate in complexity or style; rather Britten wrote this as a teaching tool for the sound of individual instruments, which groups of instruments are related to one another, and how those groups interact. Basically, on one side of an LP, the listener hears everything, in their proper locations within the orchestra. Cisco is out of business, so the LP may be hard to come by. Search it out. You won’t regret it. Anyway, going back to the SoundLab comparison, the Planetariums lack the last bit of crystal-clear, see through transparency of the big ‘stats, but it’s close. Damn close.

Let’s turn to the SWARM for a moment. I’ll be the first to admit that I’m intolerant of rolled off deep bass. I don’t care for speakers in which the very foundation of much music is missing in action. Guilty pleasure confession time: I like Rachelle Farrell’s Sista. It’s big, dynamic, and has some bass synth work that will knock your socks off. It can also sound overwhelmingly bloated. The SWARM and the main driver woofers combine here to reproduce the full depth of range, with no bloat, at virtually any volume level you can stand. I previously had a full set of RealTraps in my listening room. They are now over in a corner gathering dust. The SWARM performs its intended job so well that they are no longer necessary.

One further ‘test’ recording for bass is Ray Brown’s Soular Energy on the Pure Audiophile label. Now, I have never any system in which Brown’s bass isn’t larger (and louder) than life. The mastering engineer simply used a heavy hand on the balance here. Yet the Planetariums, at what are now my standard settings on the amp controls, do not overwhelm as lesser speakers can and do. Oh, and remember that gain control for the SWARM? Drop that down a notch from ‘normal’ and it’s even better.

Lastly, I wish to discuss the one area in which the Planetariums are, without a shadow of a doubt, better than the SoundLabs – that of dynamics. The speakers are billed as being 96 dB efficient, and of course the main speakers do not have to handle the low bass either. What this means is that my small – and quite wonderful – Atma-Sphere S-30 can drive the speakers to far more than reasonable levels with ease. Those who know me know that I listen at realistic levels (meaning uncompromised 105 dB peaks, as far as I’m concerned), and have no tolerance for compression or other nasties. As good as the new SoundLab PX panels were in this regard, there’s just no comparison. So, there you have it, horn efficiency and dynamics with none of the usual disagreeable horn characteristics. One of my test recording for dynamic range, both micro and macro, is Kodo, Heartbeat Drummers of Japan on Sheffield. Say what you will about the music (and I happen to like it), this CD will give your system a dynamic workout like no other. On the Planetarium Betas, it is awe-inspiring.

I could go on and on about which recordings sound great in such-and-such a manner, but will close this review out by simply saying that, in my case, the Planetarium Betas fulfill virtually every requirement and stroke every bias. Duke Lejeune has designed a speaker with a number of extremely interesting and thoughtful technical innovations. I’m delighted to own them.

Associated gear
SOTA Cosmos Mk IV
Triplanar Mk VII
ZYX Universe
Ayre C-5xe
The Messenger
Atma-Sphere S-30 Mk III

Similar products
SoundLab A-1PX
Innersound Eros
Various Quads
Vandersteen 5A
mbl 111
Magneplanar 3.6

I'm not sure "better" is the correct word. I've traded one set of strengths for another, but at the end of it all, I am quite happy with the choice.

Because of my personal biases, typical box speakers don't do it for me over the long haul. I miss the dipole/bipole soundfield too much. The Planetarium Betas seem very much like the 'having your cake...' cliche.
I'm not sure "better" is the correct word. I've traded one set of strengths for another, but at the end of it all, I am quite happy with the choice.

Because of my personal biases, typical box speakers don't do it for me over the long haul. I miss the dipole/bipole soundfield too much. The Planetarium Betas seem very much like the 'having your cake...' cliche.

"happier" with choice certainly implies "better" for you.

I suspect the fact Duke's box speakers compete with dipole/bipole soundfield must have something to do with Duke's attention to wide even dispersion...
Fair enough, and a good definition on an individual basis.

I suspect the fact Duke's box speakers compete with dipole/bipole soundfield must have something to do with Duke's attention to wide even dispersion...

Uh, you did catch the fact that they ARE bipoles, right? In any event, you're right. No doubt it's the dispersion design to which I'm responding so positively.
Have you considered that the room triangular cross section shape might also create some interesting and unusual refections on the rearward directed polar radiation pattern - especially with bipoles heavily toed in? It might even prove an interesting exercise in ray tracing.