@masterplan - another product I have used with great success are the 2' x 4' vinyl faced fiberglass ceiling tiles used in drop ceilings.
I created a 4" thick "brick" (about 6-7 tiles) with the vinyl sides facing out.
I covered the brick with black landscaping felt to prevent the little glass fibers from falling out.
I placed the brick under the sofa and at the back of chairs (we had hardwood floors) but if you have carpet then they would probably not be required.
You can also use them behind canvas pictures for additional damping effect.
Just use a sharp carpet knife to cut them
Regards...
I created a 4" thick "brick" (about 6-7 tiles) with the vinyl sides facing out.
I covered the brick with black landscaping felt to prevent the little glass fibers from falling out.
I placed the brick under the sofa and at the back of chairs (we had hardwood floors) but if you have carpet then they would probably not be required.
You can also use them behind canvas pictures for additional damping effect.
Just use a sharp carpet knife to cut them
Regards...