I've been thinking about these things as well. The rear wall of my music
room is mostly a large opening into the adjoining dining room. Since the
ratios are a lot better for just the music room itself I'd like to put something
between the two rooms, preferably using the dining room for some sort of
beneficial acoustic function.
The way I understand space couplers is that sound is diffused when exiting on
the far side. I imagine the sound will be even more diffused on its way back.
I've played with openings like a space coupler in the
Ripple Tank Simulator
and sound appears to be highly diffused going through them. I think some sort
of french doors with space couplers instead of windows might work well between
my two rooms.
I like the idea of a coupler as part of a cloud as well, though I'm not sure I
have enough room under my 9' ceiling for it to work properly.
Paul P