I can warmly recommend the absorbers to everyone. I put all my home cinema equipment (Denon X7200WA, Denon BDP3313UD) and especially my two Nubert AW441 subwoofers on them. The sound is absorbed very well and there is no vibration in the floor. I also find that the bass comes across clearer and with less boom. Modes, however, are not eliminated because they appear due to the sound curve. Nevertheless, you can feel the bass very powerfully. I would buy them again immediately and the price/performance ratio is absolutely right. For me, this is definitely an improvement and the neighbour will be grateful :-).