where do you hang these panels

say your room is 13'wide and 16'long. you hang a set on the side walls at 1st point,ceiling first point,where on the front walls do you hang these panels????
See: http://www.realtraps.com/art_room-setup.htm

Good Luck!
You can use the candle or lamp technique to if you have any first reflection points on the front wall (check before you laugh).

A lot of people will put them in the center of the front wall (often, there's an equipment rack there).

Then, I'd use them to make the room symmetric (if necessary)--I mean if you have absorbers on the back wall (say, an LP rack), then I would consider putting a panel on the front wall symmetric with it.

No expert, but that's my approach.
back wall is all book shelfs.just wondering front wall.thks