I have two different rooms treated with the Synergistic Research HFT (High Frequency Tuning System). With one pack of 5 tuning bullets you will hear a change in soundstage. The system really begins to shine with 15 HFT bullets in place (three boxes) and then becomes spectacular when 25 HFT bullets (five Boxes) are in place. The Synergistic Research installation video is quite helpful. It only takes a few minutes to install 25 of the bullets as they attach to the wall with included Blu Tac reusable adhesive.
With the 30 day money back guarantee I hope people who try this system will go ahead and make their initial trial 15 to 25 HFT bullets ( three to five boxes). As you put up each group of 5 HFT's you will hear the soundstage expand and then become increasingly more rich and detailed.
I found the Synergistic Research HFT + Feq system to be my upgrade of the year. Why? The marked improvement of course but even more so. Unlike the laborious trial of trying and breaking in new cables etc., the HFT's are easy to install, the sound change is immediate, and they can be returned if you do not like them. Finally in this moble changing society, they can be moved from room to room or a new city with no damage to the walls.
I will not be without them.