Can a power cord increase the resolution of an Class D (SMPS) amp by more than 5% ?

tutetibiimperes,

I know and understand why a lot of people feel power cords are just so much "snake oil". If you ever get a chance to try a few, well give it a whirl. Just keep an open mind and listen closely. You might be surprised. Maybe.....

I compared a small handful of upgraded cables in the $300-$350 range. Compared them to the stock cables that came with my equipment, I got varied results from no improvement, to a small improvement, to slightly worse sound. The differences I heard with these cables in my system was mostly in the upper bass range. Obviously the cables with the heavier upper bass made some of the lower mids sound ever so slightly veiled. I found one cable of the bunch to give me a very clean sounding upper bass which in turn gave a tiny improvement in the mids. Granted all these differences were extremely small, but I felt if I could hear a difference so it wouldn't hurt to  use them, right?  It took a week of going back and forth with these cables and was quite the tedious process. I would like to think I made an informed decision, and it would be money well spent. The cable I chose at the time was $325 new for a 6 ft. length. I found several  more of these cables used on Audiogon in a range of $120 to $150 each, so I bought them to wire my entire system. I do like the result, but I don't think I would buy mega buck power cords. IMO. 

I have a Class D hybrid integrated amp with Hypex-400 modules.

I've heard the tiny improvements or worsening of the sound for that matter, in regards to power cords. While I never experimented with the mega buck priced cords, do they offer any real world improvements over more modestly priced cords? It seems to me there is just so much one can do with the AC coming from one's outlets. I suppose I'm just stating the obvious. I'm not an engineer of any variety. lol.

Please read Michael Fremer's short review of Audioquest Dragon Source power cords in May 2018 issue of Stereophile, and form your own conclusion....

azbrd,

I totally agree with you. I have heard minute differences with some upgraded (and somewhat inexpensive) power cords. Most of that being tiny variations in (audible) frequency response. I was just bringing to attention to the large variation in SQ that Mr. Fremer claims to be hearing. It is most definite that I do not agree with him. But that is just my opinion. I cannot afford to dish out several thousand dollars for power cords and even if I could, I'm not sure I would....