Mofojo,
Steve Deckert of Decware helped me with placing the quadratic diffusers at the first reflection points on the ceiling, one side wall and on the back wall along with building floor to ceiling bass traps in each corner and hanging heavy velvet curtains on the side wall without the diffusers. We also decided to cover all of the exposed ductwork with acoustic foam. The room sounds great. Building a dedicated room was one of the best audio investments I've made. I wish I could share some specific wisdom for your room, but I pretty much followed Steve's advise. My room is in the basement with low ceilings, 7'6", so I guess the bass traps are more necessary. Placing diffusion at the first reflection points seemed to really help along with carpet and padding on the concrete floor. After that experimenting with absorption throughout the room, especially where the walls meet the ceiling would be the extent of my advise. Hope that helps.
Steve Deckert of Decware helped me with placing the quadratic diffusers at the first reflection points on the ceiling, one side wall and on the back wall along with building floor to ceiling bass traps in each corner and hanging heavy velvet curtains on the side wall without the diffusers. We also decided to cover all of the exposed ductwork with acoustic foam. The room sounds great. Building a dedicated room was one of the best audio investments I've made. I wish I could share some specific wisdom for your room, but I pretty much followed Steve's advise. My room is in the basement with low ceilings, 7'6", so I guess the bass traps are more necessary. Placing diffusion at the first reflection points seemed to really help along with carpet and padding on the concrete floor. After that experimenting with absorption throughout the room, especially where the walls meet the ceiling would be the extent of my advise. Hope that helps.