I did get 2 of these and they did make a marginal change in sound. Maybe I need some crystals and copper to enhance the effect?Improving the room is the FIRST thing to do in audio... S.G. are way down the list even if they work ....I owned 12 then.... 😁😊
But NOTHING will replace the huge improvement of passive materials treatment and active one with Helmholtz tubes and pipes.... Not even upgrading all the audio system...