@bemused , I have been a pretty hard core enthusiast in more than 20 yrs and have far more tweaks and power conditioning gear that could be considered as "normal". For example, I have more power conditioning gear on my regrigerator or my freezer than other entusiasts have in a large stereo system. So yes, it makes a huge difference. Actually, I have tweaked my systems so heavily that it is easier for me to hear upgrades I do on other ac lines, like the ones for refrigerator, freezer, ventilation etc. I don’t say that should be normal, but that is how it is in my house, even with dedicated lines, upgraded fuses in my meter board etc.
So I don’t use one brand of power conditioning gear for these devices (refrigerator and freezer), but from many brands,typ. Ansuz, Nordost, ADD Powr, High Fidelity, Furutech and Telos. I also have Darkz damping feet for several of these, Furutech distributors and high end power cords - and even Shakti stones behind them... go figure! Yes, I know it sounds crazy, but I wouldn’t change it:) If I remove one piece I easily hear it in my stereo.
@justubes2, I find the Nordost QWave to be stronger than the Qv2, it is also supposed to work not only in lower bass region as the Qv2, but also upper bass. The QSine is kind of invisible, but just makes everything more transparent, also in higher frequencies, gives more air and bigger soundstage. It is easy also to see with video, the picture gets crystal clear. I find it to be better and more neutral than Qk1. It can remind a little of ADD Powr, but still they are different, hard to explain... IMO, both QWave and QSine do not limit dynamics at all. I have never tried Purons.