I have 8 of these absorbers bought to my subwoofer (Jamo 660) from the laminate floor to decouple. Previously, one could perceive noticeable drone, which was caused by the vibrations on the floor. After I had positioned one above another 2x these absorbers on each edge of the subwoofer, this Dröhen had disappeared. Now I can the subwoofer even a bit louder places, at some point it is then but the walls resonate and want to do not my neighbor.
I can only give this absorbers 5 stars because they meet the targeted use of me perfectly.