If you are a real fan of the Eikona drivers, you could use two drivers in a doubled size enclosure on each side of the soundstage. If you aim one driver forward in the enclosure and aim the other driver backward with the drivers fed in-phase, you would have a bipolar radiation pattern. Connect the two drivers in series for your 16 ohms preference.
Jim
Thanks, Jim.
Since I tend to run solid state amplifiers, my preference is for 6-8Ω overall impedance; hence my wish for 12-16Ω drivers, so that paralleling them would yield 6-8Ω.
Ultimately, I would like to build two enclosures if I were to go with two drivers per side: one with the drivers stacked vertically and the other as you suggest; in a bipolar array, like the early 70s EPI Microtower, but perhaps with the drivers not so close to the top.
This configuration would also allow me to re-visit an effect I have not had the pleasure of repeating since around 1977 when I put a couple of 12" CTS drivers with an fs of around 21Hz back-to-back in a sealed box in a bi-symmetrical arrangement suggested by some English engineer writing in perhaps Studio Sound or HiFi News. He called it 'acoustic feedback', if I recall, and it had the supposed characteristic of the two drivers' resonances cancelling each other out. My immediate skepticism lasted only until I looked at the published impedance curve running through what should have been the resonant zone. It was flat ±1.5Ω right through the bass drivers' range.
Thus inspired, I built it and that is exactly how it sounded; like there was no resonance at all. This was the cleanest, least resonant bass I have ever heard, and it made reflex boxes, sealed boxes—even infinite baffles (I had a pair of 12s in the living room floor, backs to the basement) all sound laughably resonant.
Anyway, the Eikonas look to be custom made either for that configuration or as a small, elegant single driver box and would be fun to play with, even if a little expensive.
PS, I also like that two drivers per side would reduce the need for baffle step compensation and the bipolar configuration creates a more frequency-balanced room sound.