Blankets and pillows can be your friend when experimenting. Cover your TV, and put up a make shift absorber on the sides.
If you do put something on the sides, again, due to lack of materials, go for a thick panel, but now you should consider diffusion as well. Look at the GIK impression series. They can come with feet, so you could for instance put a diffusor in front of your TV while listening and move it out of the way when you need to.
If you do put something on the sides, again, due to lack of materials, go for a thick panel, but now you should consider diffusion as well. Look at the GIK impression series. They can come with feet, so you could for instance put a diffusor in front of your TV while listening and move it out of the way when you need to.