Two concrete reasons why some power cords might work better than others:
1) EM shielding, which can work both ways.
2) current delivery, which may be beneficial for high power amps in some cases, but probably not all.
Power conditioning often helps as well, but I do not view that as part of a power cords job. Other devices better suited for that if needed.
Night and Day is a strong yet ambiguous term. It really only means there appears to be a discernible difference as opposed to not. It will likely be small on the grand scale of things with power tweaks in most cases, but enough to be significant for those whose ears are very well tuned in, which tends to be the case with most "audiofiles". Beyond that, when a difference is heard, it can be hard to attribute to the known change versus perhaps some other unknown factor, like changes in our own physiology day to day and how that might affect what we hear.
I preach the approach to try tweaks if there is a good value proposition and some clear reason to expect it might work. But go easy, don't flush a lot of money down the drain. Look for value and good customer service/return policies if not satisfied.
"Magic" or even pseudo-science alone is not a good reason to try something.
1) EM shielding, which can work both ways.
2) current delivery, which may be beneficial for high power amps in some cases, but probably not all.
Power conditioning often helps as well, but I do not view that as part of a power cords job. Other devices better suited for that if needed.
Night and Day is a strong yet ambiguous term. It really only means there appears to be a discernible difference as opposed to not. It will likely be small on the grand scale of things with power tweaks in most cases, but enough to be significant for those whose ears are very well tuned in, which tends to be the case with most "audiofiles". Beyond that, when a difference is heard, it can be hard to attribute to the known change versus perhaps some other unknown factor, like changes in our own physiology day to day and how that might affect what we hear.
I preach the approach to try tweaks if there is a good value proposition and some clear reason to expect it might work. But go easy, don't flush a lot of money down the drain. Look for value and good customer service/return policies if not satisfied.
"Magic" or even pseudo-science alone is not a good reason to try something.