I recently took possession of a pair of Duke Lejeune's Planetarium Betas, which consist of a pair of main speakers with two 12" woofers, mounted front and back, and a pair of 1" compression, waveguide-loaded tweeters, also mounted front and back. The idea behind the design is to produce a "controlled-pattern bipolar configuration". The mains are specifically designed to roll off at, by my estimate, 65 Hz or so. Below that, music is handled by what I consider to be the truly innovative part of the system, the SWARM. The SWARM is a set of 4 small subwoofer units, each with an 11" X 11" footprint, and utilizing a ported 8" woofer (tuned to 25 Hz). The subs are driven by a very flexible 1000 watt amp. The idea behind the SWARM is to place them at locations at varying distances from room boundaries, with each sub having its own room response, and thereby producing a much smoother overall room response when output from all four is summed. In my own field of expertise (geophysics), this is known as minimizing constructive interference. Does it work? Boy, does it ever. I had thought that my previous speakers (SoundLab A-1PX) were relatively impervious to room effects. They are, actually, but not nearly to the degree that I had thought. I am now enjoying the best bass, both in quality and quantity, that I've ever heard anytime, anywhere, in nearly 40 years of audio experience. Those looking to extend their bass response (Quad, Maggie, and high quality monitor speaker owners spring to mind) should definitely give the SWARM, which apparently is sold as a standalone system too, some serious thought.
I'm still trying to get a firm handle on the overall sound of the Planetarium Betas. The process is complicated by the fact that I have a brand new amp as well (Atma-Sphere S-30 Mk III...did I mention that the speakers are 96 dB efficient?), which is breaking in. I've never seen any piece of electronics that changes its sound so drastically almost by the hour as the break in proceeds. Regardless, I'll mention two very distinctive areas of superiority that are evident even now. The soundstage is extraordinarily wide and deep. I know many audiophiles who do not place a particularly high priority on this characteristic, but I'm most definitely not one. It is very, very striking. Dynamic capability, as might be expected from what's technically a horn-loaded system, is outstanding. Now, I've never been a big fan of horns. Regardless of the protests of horn enthusiasts, I could always hear that 'horny character'. The waveguide in the Planetarium beta produces none, at least that I can detect at this stage. So, we have the benefits of a horn without the downside. I love it.
In this world of 'yet another variation on the box stuffed with OEM drivers', I love seeing the innovation, particularly when it works SO well. And even more particularly, when I'm the beneficiary!