Dave Clark has posted a review of the Nordost Qv2 and Qx2 power conditioners ($1799/each and $2699/each, respectively) at Positive Feedback. His conclusions:
“So yeah, with the Qx4 in place the soundstage becomes bigger still. The speakers disappear that much more, instruments and textures take on even more presence and definable space, the sensation of the room being pressurized is more readily apparent and appreciated, timing and rhythm is even more involving… like there is less of that something in the way: a lot less of that something. I hear more with, than without. I hear more of the music, but what is cool is that I don’t hear a change to the music. There is no shifting of whatever so this stands out from that—no harmonic or tonal emphasis or de-emphasis. Neither do the units soften or edit what is there. There is no sense of there being a sameness to the music when they are in the system—you know, the way some devices can make everything sound dull or bland by taking away the life and sparkle, or by adding some sonic signature of their own into or onto the music. No, the Q products just do what they do to the AC, thereby allowing for more of the music to be felt and appreciated. I like what they do. Not necessarily affordable, but they do work as advertised – here at least. AC is a funny thing, well not a Ha Ha funny thing as AC can be a very scary thing when you wrap your hands around a live wire and do the jumpy-dance… no it is a funny thing in how some AC filter/treatment devices can either be mind altering or ho-hum in what they can do. Your AC is not my AC…. what is happening on my grid is not necessarily happening on yours, so your mileage may vary—got to try before you buy.”
You can read the full review here.