Well I'm the guy to add to this topic.
The SpaceCoupler was developed and manufactured by Russ Berger's (of
RBDG [Home]) Part Science brand of acoustical products that are sold through Auralex.
It has two great and distinct applications:
(1) to accomplish Russ's "loosely coupled space" design approach as defined by his AES white paper from mid 90's (forget year off hand). This design theory can be oriented vertically or horizontally. One volume of space is typically larger with low decay time. A second volume of space is typically smaller and reflective/diffuse. between the two is an aperture (opening). In Russ's large facilities...you don't even see this at play as it is so ingrained in the architecture. The SpaceCoupler allow say a 13'x15' room with drop tile to be a version of this. You want 3' of space between grid and deck above. Use in range of 30% coverage of Couplers...placed to outer edges the result is a warm secondary ambience...placed in center of room the ambience is brighter. The secondary space has a decay slope that varies from lower and the result isn't a big room sound...but a bigger space sound. Very musical.
(2) extend the depth of absober and/or skew specular reflections without removing energy from space. These applications are again best used in relation to all space...meaning just a Coupler or two may or may not have any bearing on space...but at the same time, I've very succesfully used them in ceiling clouds to greatly diminish floor/ceiling axial mode while creating increasing detail and imaging due to diffuse energy retained in mid/hi. Often I consider them a "food processor" acoustical tool.
Not for every application...but that being said...truly one of the most effective tools for small room acoustics to come forth in this decade.