This is a review and detailed measurements of the audioquest Niagara 1200 Power Conditioner/Filter and Surge Protector together with their NRG-Z3 AC power cords. They are on kind loan from a member. The Niagara 1200 costs US $1,000 and the power cords costs US $200 in 1 meter length and $280 from Amazon including Prime shipping. So the total package tested costs US 1,480.
Company claims in one of its interview videos that AC mains can "distort or mask up to 1/3 of your low level content." And that any differential probe can show it.
Well, I used a differential probe and can't find any such evidence. Even the AC distortion itself is not filtered let alone be 30%. Let's have the company show us this if it is so easy to measure and presumably, they have done so. Why keep such measurement hidden? Wouldn't sell more product?
If you want to spend $1000 on a sturdy box with surge protection, go ahead. But please don't assume it does something for your sound. It does not.
Needless to say, I can't recommend the Niagara 1000 or the RG-Z3 AC power cords.