I've tried various pc in the past and most do change the sound one way or another. A/B doesn't work for me, it usually requires atleast 3-4 days for the differences to by fully noticeable. I have just in the past month went through three different pcs on my source. The first 3-4 days they all sounded very similar, with the only slight noticeable difference in the bass area. After 4 days or so, the differences became more apparent and each takes my system to a slightly different direction.
I don't know the technical workings of this (feel free to jump in Sean,) but I think it has something to do with the pc itself being electrically charged up. From my experience and imho, the neuances of each cord would only reveal themselves after this length. Any A/B comparisons that I have done prior to said time often yield inconclusive results. If I had only done A/B comparisons, I may have drawn the conclusion that they make no differences.
I don't know the technical workings of this (feel free to jump in Sean,) but I think it has something to do with the pc itself being electrically charged up. From my experience and imho, the neuances of each cord would only reveal themselves after this length. Any A/B comparisons that I have done prior to said time often yield inconclusive results. If I had only done A/B comparisons, I may have drawn the conclusion that they make no differences.