Schipo - I can't really tell from your description, but do you mean the "Skyline" type of diffusers is what you're interested in possibly building? If so, then the best Skyline calculator I've found and used is found here:
http://www.oliverprime.com/prd.php
I have a written up Word doc on how to use the site and how to build them using wood. Within my system are pics of the Skylines I've built, both with a painted and polyurethaned finish. I think the latter looks better and adds 'warmth' to the room.
If you're interested in building a hemi-cylindrical diffuser like what RIVES puts on the middle of their client's front wall, then I've done that several times and can share the details too. System pic also have a picture of it. . .
http://www.oliverprime.com/prd.php
I have a written up Word doc on how to use the site and how to build them using wood. Within my system are pics of the Skylines I've built, both with a painted and polyurethaned finish. I think the latter looks better and adds 'warmth' to the room.
If you're interested in building a hemi-cylindrical diffuser like what RIVES puts on the middle of their client's front wall, then I've done that several times and can share the details too. System pic also have a picture of it. . .