OK I’m an electrical engineer who has never tried to play with power cords. This means I know just enough to be dangerous but not enough to really know what I’m talking about. I am not going to claim that power cords do not make a difference because I suspect they do. That said, here’s my 2 cents.
Electrical power cord as filter: I’m not convinced but… The parallel is a fuel or water filter. Water travels for miles in dirty pipes but the filter at the end is able to clean it up. This argument does not work with power cords. A power cord is the last section of pipe, not a filter at the end. As such the analogy would be miles of dirty pipe with a clean section at the end. Not adding dirt for the last few feet isn’t going to help. A power conditioner is a good analogy to the water filter. IF the power cord has some form of filtering built in, that would be different. A power cord might include a high frequency filter to clean RF noise or something. Even if the designer didn’t intend it, the geometry of the wire could make a filter of some sort (I wouldn’t put money on it). Basically, I don’t by the filter part unless some form of RF filter was deliberately added.
Electrical power cord as the last few feet of pipe: Using the water analogy
1. The original pipe was too small (ie wire gauge too small). If the power cord was too small to handle the current you could get voltage drops. My 240wpc Bryston amp came with a heavier power cord than my Bryston preamp. Thanks to V=IR loading on the power lines and cord the amp might see a significant reduction in line voltage. I would expect this to hurt amplifier performance. If your system is plugged into a power strip this voltage drop might be shared with the other components in your system.
2. The pipe has flashing around the fittings (ie the plugs don’t mate well). Maybe the issue isn’t the last few feet but the connections at the plug. Just like the issue with small gauge wire, a bad connection can cause a voltage drop. This would explain why high quality hospital plugs can make a difference.
3. The last few feet of pipe is where all the dirt is! Perhaps the power from the wall isn’t that dirty but all your equipment is really making the noise. Shielding the cables as they near this big rack of electronics may make all the difference. Perhaps the worst dirt is the dirt generated by your own system feeding back into itself. This could explain why shielding may help.
Take it for what it’s worth. Personally I think cables make some difference but I would rather spend the big money on components rather than cables.
Electrical power cord as filter: I’m not convinced but… The parallel is a fuel or water filter. Water travels for miles in dirty pipes but the filter at the end is able to clean it up. This argument does not work with power cords. A power cord is the last section of pipe, not a filter at the end. As such the analogy would be miles of dirty pipe with a clean section at the end. Not adding dirt for the last few feet isn’t going to help. A power conditioner is a good analogy to the water filter. IF the power cord has some form of filtering built in, that would be different. A power cord might include a high frequency filter to clean RF noise or something. Even if the designer didn’t intend it, the geometry of the wire could make a filter of some sort (I wouldn’t put money on it). Basically, I don’t by the filter part unless some form of RF filter was deliberately added.
Electrical power cord as the last few feet of pipe: Using the water analogy
1. The original pipe was too small (ie wire gauge too small). If the power cord was too small to handle the current you could get voltage drops. My 240wpc Bryston amp came with a heavier power cord than my Bryston preamp. Thanks to V=IR loading on the power lines and cord the amp might see a significant reduction in line voltage. I would expect this to hurt amplifier performance. If your system is plugged into a power strip this voltage drop might be shared with the other components in your system.
2. The pipe has flashing around the fittings (ie the plugs don’t mate well). Maybe the issue isn’t the last few feet but the connections at the plug. Just like the issue with small gauge wire, a bad connection can cause a voltage drop. This would explain why high quality hospital plugs can make a difference.
3. The last few feet of pipe is where all the dirt is! Perhaps the power from the wall isn’t that dirty but all your equipment is really making the noise. Shielding the cables as they near this big rack of electronics may make all the difference. Perhaps the worst dirt is the dirt generated by your own system feeding back into itself. This could explain why shielding may help.
Take it for what it’s worth. Personally I think cables make some difference but I would rather spend the big money on components rather than cables.