If i were painting the panels. I would start with a coating to seal the material. A waterbased flat paint, some sort of primer. A dark color primer.
You could ask the paint dept at the store what would be a suitable brushed on primer for the material.
Then just use the same paint that is actually ON the walls would be fine.
This warning is on the RPG site:
WARNING:
The Skyline® is fabricated from flame- retardant, high- density expanded polystyrene foam. It is the nature of this material to have rough surface imperfections and contain steam vent holes. Some of these imperfections can be partially concealed by a factory paint process. If you are interested in a painted product, RPG® offers a painted version in Duron Multispec Fine Fleck paint. RPG® does not recommend that the Skyline® be painted in the field and assumes no responsibility for any damage resulting from field painting.
BUT:
So as long as you use a primer suitable for the polystyrene foam, you are good to go.
(IMO you will have zero problems painting the panels IF you use a proper primer coating.)
Added: the panels are a size for a specific frequency.
If you used the calculations and made panels that were sized for the problematical frequencies in your room, they would be more effective.
If you just Google RPG Skyline, in the first page are a discussion of do it yourself with several lists of the calculations, and referneces to the method of calculation.
If I were to use the theory (which by the way is NOT copywrited for making panels) you could make panels suitable for any room
This comment is more for others interested in these devices...
I would make some out of wood... though that is a very heavy and work intensive process. Other materials might work too.
Making one, and replicating that one in a poured material from a home made casting could be the easiest means of making many of them.
