I have a small phone room at the back of the office. It's around 5x6, has a ~10' ceiling, a large window, and a full-height glass wall and door on one side. The walls are brick on two of the other walls (exterior) and dry wall on one.
Now to get to the point: The room is extremely echo-y, understandably with the glass wall and hard surfaces. I'm looking for an aesthetically pleasing and relatively affordable way to deaden echoing.
I've considered wall-mountable foam like this, but I'm not sure that's the right solution or how I would most effectively mount them (where on the walls, how much to use, etc).
Pictures below. The boxes you can see are not normally there. The shelving is just to the left of the window.
Any suggestions are appreciated!