I purchased this type of isolator for my subwoofer on 21.03.2019 and I am very satisfied with what it does. I bought two pieces for my two REL T5i subwoofers. It does its job very well, which is to decouple the subwoofer from the floor and reduce the structural vibrations caused by direct wave. Basically, a subwoofer causes two types of vibrations: DIRECT VIBRATIONS caused only by the movement of air in the room (as if the subwoofer were suspended in the air) AND INDIRECT VIBRATIONS caused by the movement of various types of materials in the room due to the fact that the subwoofer is on the floor (the vibration of sofas, chairs, glasses on furniture, chandeliers). So, before buying this type of isolator, I had both types of vibrations; now I only have the direct vibration caused by the movement of air in the room, as if the subwoofer were no longer on the floor but suspended in the air. Also, this isolator has the role of enhancing low frequencies, improving sound clarity, and reducing resonance, due to the fact that it decouples the subwoofer from the floor. In conclusion, I am very satisfied with my choice and the promptness shown by Sound Creation, especially since this order was special, as they did not have this product in stock at that time.
