Ideal control room shape: Main conclusions=confusion

i would add a treatment wall over it but you could be creative and have reversible treatments over the concrete in sections (if it doesn't disrupt the isolation you want) and expose the concrete. I think Scott's tracking room is about 9m but it slopes all the way to the roof with various treatments all around.

Ok, i finally got it! Well, it is very daring, indeed! Just have to be sure the isolation is as effective between the parts, as if we had only one isolation wall, when concrete is hiden. So you are with the idea of getting the final room shapes made with isolation/treatment room... Because there's that common idea that an isolation wall would have to follow the original shape (rectangular), and then the treatment walls giving the final octogonal shape.There's the point of calculating room modes there, as some say it is easier to have rectangular-based massive wall, than angled walls...Here i would love to hear from John advices, as i always seen his wonderful layout following the principle of angled walls, but never understood if these were massive walls, or not (just treatment parts). Anyway, as with your system, isolation walls would have to be angled anyway, since they're the same than treatments ones: About your suggestion some would say it is more difficult to know where null and nodes are, but by myself i really don't know what's the best! :?

the key is to use broadband treatments. and by using angled slat resonators, you get a decent range of frequencies covered and you get angles which break up the flutter echo. staggering the treatments on opposite walls introduces some diffusion to the space. and this should be done in 3D if possible and paying close attention to the corners of the rooms since all room modes terminate there and therefore treatments are more effective in those locations.

Well, Gullfo, thanks for all your helpful replies! Ok, so... beyond the idea about inside-out walls, i conclude these 2 steps in any 'regular' walls configuration (tell me if i am righ with that step by step concept): 1) Rectangular isolation (along the original wall) : These massive walls allow room modes calculations (it is also possible to adapt thickness isolation wall, to determine correct inner room size).Once one knows the room modes behavior of that room, one can find the best way to treat the resonances. 2) Add Treatment parts as you described just above, given the resonance pbs of the room; this step would give the control room its final shape. Well, am i in the right direction? :roll:

pretty much. while the mode calculations will help spot major trouble areas, you're probably best off thinking about broadband treatments, and once you have those applied, do some measurements to find any remaining trouble spots.