I bought five more. So with seven, I will see how it goes...Immediate impression is the background black is 'blacker'..Noticed watching PBS TV "Arthur" cartoon the smooth blobs of color are totally free of grain, perfectly smooth. Enough to note it.Treble seems a tiny bit sweeter in stereo. Little more detail in general.
Two on amp line. three on Furman (One on high power, used for preamps, one at Plasma TV one at Marantz SA-10) , one on PS Audio P-600, and one at powercord to Furman.During normal stereo operation, only the one on PS Audio P-600 where five disc CD changer is blinking at all.Plasma TV turned on makes the two on Furman blink like crazy. IPlasma off no blinking)
Dimmer in bedroom at half on only makes the amp line pair blink a little.
I am of the opinion that even with no blinking, the Noise Harvesters may be doing something...