Hi,
I have a second system in the attic and the room is an odd shape. L shaped room with a 4x4 m square adjoining a 4.5x3m oblong with part sloped ceilings and a little alcove etc.
There is some carpet/rugs on floor in front of system.

Looking to improve sound stage and stop reflections from the long sidewall and alcove, also to experiment with bass trap or similar in corners and behind speakers etc.
Some sort of covered panels would be good-cost effective please