erndog, the OB/Dipole sub needs to be placed as all dipoles do---not less than three feet from the wall behind them. If they are paired with dipole main speakers, no problem, as the speakers are already there. They can, however, be placed right up against a side wall, as there is a null to each side, a result of the front and back wave cancellation. The OB sub, by the way, uses the same woofer as that of the Rythmik F12G, but optimized for Open Baffle use. It can be used as not only a sub, but also a woofer, crossed over as high as 300Hz.
The sub sounds quite different from sealed and ported subs, without the room-loading boom, fatness/thickness, and all-too-often "lagging-behind-the-speaker" sound of them. They have the "start and stop on a dime" sound we all want. Leaner, cleaner, more transparent, like the bass produced by the 3-panel Maggies---the Tympani T-IV and T-IVa---but with far more output, far less distortion, and far deeper response. The woofers are not only NOT loaded into a bloat-producing box, but are controlled by the Rythmik Direct-Servo-Feedback system included in the plate amp. An Open Baffle woofer with servo-control---the only one in the world, and a game changer imo!
Imagine the sound of an open baffle loudspeaker, but with response into teen frequencies. The way it reproduces the woody resonance, growl, and percussive "plunk" of the acoustic stand-up bass (whose open-E string produces a 42Hz tone) is unmatched, in my experience, the fundamental (produced by the sub) and it’s harmonics (produced by the loudspeaker) in complete sync. The left-hand registers of a grand piano are just as clean as the right. The OB sub doesn’t sound like a subwoofer has been tacked onto the bottom of your speaker, it’s response trailing behind the speaker’s like the caboose on the end of a train. It instead makes your speaker sound as if it’s response has been extended down into the very lowest frequencies, leaving the speaker's character unchanged and intact. Isn’t that what you want a sub to do?!
