Why power cable effect overall syste sound?


Power cables effect the system sound. This is a well-known fact. My question is why.. specially in case of low power type "A" amplifiers where current is constant. In my single ended 300B the cable creates huge difference. Does it points on power supply PSRR issue? Actually in case of well designed power supply, the power cable should not introduce any improvement. We are spending hundreds of dollars for the 1 meter of cable from outlet to IEG socket where meters of cheap wires running in the walls and it does work. The answer on this question is puzzling me.
abronfer
The benefit of power cables is far overrated. The benefit depends on RF EMI contamination present. They can reduce noise, but when people start claiming huge improvements in sound, etc., I get a little skeptical. Use a cable of 10-12ga, and this should not limit the current. Shielding is a plus, and don't forget to notice the size of wire in your transformer, and how long it is, maybe 20-22ga. Also, the unshielded wire in your house, all 75ft. of it. Magic in the last 6 feet??? Just eliminate a bottleneck if one exists. There are other things to spend money with a bigger return in MHO. Good matching with your amp and speakers is far more important, and getting the damping characteristics matched well. Jallen
Power cables affect the system sound. This is a well-known fact.

OMG here we go again for the zillionth time. Yes they do so unquestionably. I never used to believe it until I actually tried it. And now I have about $15K just in cables. I gave up a long time ago wondering exactly why though. I don't understand it fully either, but what does it matter? I don't completely understand exactly how my car works either, but I still drive anyway.
I GUESS THOSE OF US WHO HAVE ACTUALLY TRIED AND WORKED AT THIS IN OUR highly resolving systems must be deaf or part of some huge conspiracy? I am amazed at some here on Agon? I must assume that we do not all have the ability to hear the difference. I suppose that is possible as we are all created different.

As far as the argument of miles of wire in the house and throughout our communities before our 3 foot power cord, well why bother with any special wire inside our gear or caps or connectors or any high quality parts? That argument makes no sense to me at all.

Power cords, tube rolling, audio racks, room treatments, speaker wire, IC's, speaker placement, burn - in and tweeks all make a big differnce. If you don't hear them, then that is true for your God given set of ears.

I trust those of you who can't hear the difference either have not tried or really can't. Just don't tell me and others we are not telling the truth or have been tricked.

We must account for the fact that we have differing abilities to hear changes in sound. I choose to believe we are all being honest here and are simply sharing our actual experiences.

I know this to be true in the food business. Not all people share the same ability to taste a change in a food product. As a product manager I have learned some cannot taste the difference when we change a product while others can (blind testing). The same is true for the other senses like hearing.

There are some good responses, but this has been asked and answered so many times so a search might help avoid a new round of "heads in the sand".

Also, this is a fun name calling and pot-shotting topic for arm-chair paper tigers so its hard to sort through the BS when asking seemingly straightforward questions.

Here are a few simple, straightforward explanations in layman's terms..

One of the fundamental reasons any decently designed after-market power cord can make a difference is that noise generated and shared within interconnected systems poses a far greater challenge to resolution and fidelity than externally generated AC interference. Just as it is within electronics themselves, the laws of proximity rule when it comes to the effective treatment of radiated and power supply generated noise.

Power cords are designed to act as sympathetic, noise-isolated extensions of the primary winding within a component’s power supply. Seen this way, their function takes on a more understandable role. They represent the initial outward electrical interface for each piece of electronics in the system. That raw wire interface can either act as an antenna for radiated HF and ground-borne noise or it can be engineered to isolate the power-supply port from internal and external EMI, RFI interference.

There is no such thing as a power supply that is adequate to filtering or isolating itself entirely from the huge volume of gigahertz noise that surrounds electronics systems and comes from within them. The bigger and more powerful the system, typically the larger the problem an unshielded or unprotected AC port can become. That is not to say electronics systems cannot sound great without after-market cords, or that tons of money must be spent on them, it's just to say that there is real-world science that explains why that they "can and most often do make an easy to hear difference or improvement in recorded or reproduced sound".

In general, power cords do not represent the last few feet of an AC grid leading to a component; they are first few feet from the perspective of each component’s power supply. Due to the fact that your AC is in principle the_source_ of sound for any music or sound system--AC rectified to DC which carries the signal through the system--it would seem imprudent to ignore the possibility of a difference and not perform the simplest of empirical experiments for oneself--unless the point of discourse is only to make funny asides under strict internet protection :o).

Since no product of this or any kind are being forced on anyone, each is free to try for themselves and make their own determination. Certainly the fact that many of the finest recording studios, mastering professionals, electronics engineers speaker manufacturers openly use and endorse them would seem to dim some of the more ardent "internet posting professionals" erm, arguments...

Grant
Shunyata Research