I got 2 of these from Amazon...careful that free returns are applicable. I charged them up, turned them on and holy moly.....they do help with my system. What I hear is clarity....space between instruments, a definite difference in upright and electric bass, wider soundstage...you know...all the good stuff. At first I thought it might be increased brightness, but no....it is still the same in that regard. I still can't believe it, and will listen again tomorrow (saved the packaging for the return)...but today, I'm about to keep them.