[Sonny]

Hi all, I know this is an old thread, but I thought I try to see if anyone is still active.  So I have all the wood cut, thanks to a neighbor, and am making four of these.  I plan to put two on the front and back walls... are these the best places for them? I hear that for a small room like mine, 14x19x8, that it's better to have absorption on the side walls and ceiling at first reflections and diffusers on front and back walls. Any thoughts?

Will have four of these.
https://www.google.com/search?q=skyline+diffusers&client=safari&hl=en-us&prmd=sivn&source=lnms&tbm=isch&sa=X&ved=0ahUKEwip-JOZp8DSAhUIr1QKHXr5C5YQ_AUICCgC&biw=320&bih=460#imgrc=3KoKtifpORXJ4M:

[Big Red Machine]

Try them at first reflection points. You might be very pleased. My room is only 2 feet wider and that is what I do. Absorption is overrated.

[Sonny]

Thanks will do when I finish sanding and then gluing!  I will let you know.

[JLM]

I've read that side and back walls are ideal for diffusion, but why not experiment?  (And then let us know.)

Room shape/size is the greatest advantage (your's is close to my 21ft x 13ft x 8ft room).  That with proper speaker/listener setup (look at Cardas near-field) makes my treatments nearly pointless.

[JWL.GIK]

Excellent! Congrats on your build. 

I prefer thick absorption at reflection points for several reasons, the main one being that thick absorption has a much wider effective bandwidth than a skyline diffusor such as the one you are building, which most likely will be effective from somewhere between 500-1.5kHz up to 2-4kHz or so, ie, a relatively narrow part of the midrange.

Diffusors are great tools! But a skyline diffusor with nothing else at reflection points means that you will still have a pretty good amount of sound reflecting toward your ears.

If that was my room, I'd use the diffusors on the rear wall, along with a lot of bass trapping back there.