Calculate a Two-Dimensional Primitive Root Diffuser
What?!
If you like to learn about room acoustics, this book was among my former audio collegues from the Fraunhofer IIS considered to be "the bible":
http://www.amazon.com/Acoustic-Absorbers-Diffusers-Theory-Application/dp/0415471745
Why?
This script exists because I had to have the computer calculate the diffuser dimensions. It took little effort to make it also available for other people to do the same with even less effort!
What frequencies do I set?
Depends on the room. And what sound you want to achieve. For example, a furnished living room with carpets etc will not need much high-end diffusion because there are already many small objects that diffuse the higher frequencies. An empty glass container would need a lot more.
Note that the human ear is most sensitive to sounds in the frequency range around 3-5 kHz. So choose a width of the blocks small enough to comfortably cover this range.
Low-end diffusion can be tricky simply because of the tall blocks required. Go as low as possible/reasonable considering room dimensions. Note that the architecture of the room can account for low-end diffusion already.