Joachim,
With this principle it will be impossible to "create" a larger (more deep) room than you have. Thus, sound will never go beyond the wall's boundaries. There are no tricks applied here and all is just acoustical (reflections).
Although I never heard it, I think people say that a (DSP) system like Lyngdorf has it, can go beyond walls. But the same people claim headaches and other anomalies coming from that (just getting literally sick of it).
You can't fool nature (physics) I guess.
Something else is that I am pretty sure that a system which relies heavily on reflections (like this Beolab 90 does) will sound heavily messy.
Thank you - it was a nice watch with my Saturday morning coffee.
Peter