The loading of the woofer is at least as important as it’s size...not saying the Cubus is mistuned or anything but size alone won’t tell you much. I actually preferred the bass on our Dynamikks 10.15 (15 inch) over the bass in the larger 12.18 (18 inch).I'm not a fan of Acapella speakers but I have been impressed by their Ion tweeter. I imagine the plasma tweeter in the Cubus sounds fantastic.
I also like the idea of the 18" woofer. I had imagined that both of these would perform well beyond the Odeon 33 or 38.
Is the horn midrange of the Cubus, however, vastly better than the Odeon models as well?