How can power cords make a difference?

Albert - Since I don't know all the laws of science, it's more than a little presumptious of me to claim that an effect must be outside all known laws. So, sticking to the few laws I do know I checked the resistance and voltage drop of 18 vs. 12 gauge line cord. I know claims are made that there are other effects of some kind that are more important. Anyway, I thought you might find these numbers interesting as they help keep things in perspective.

Assuming that your DVD draws about 10 watts, a 6 ft 12 gauge cord will drop .0016 volts while the stock 18 gauge cord will drop .006 volts. Now, it is typical for your utility voltage to vary 10 volts during different times of the day. Also, good gear is design to handle two or three times that amount without any problems. So, the voltage stability provided by the larger line cord is somewhere around 1 to 2 thousand times smaller than the normal variations of the utility's voltage.

I picked my analogy of the pump nozzle effecting the performance of the car because it is similar. Electricity is pumped to your power supply where it is transformed, rectified and stored for (by electrical time standards) later use. Much like the gas from the service station pump doesn't flow into the engine, the electricity from the line cord doesn't flow into the digital/audio circuitry.

It is this tremendous isolation between what is happening at the line cord (330 peak to peak volts) and what is happening at the circuitry level (low nearly perfectly regulated dc voltages) that make it incomprhensible that the minute contributions of exotic lines are significant.

Hey Albert, have you found it odd that "the" guy who claims no possible change can take place from a power cord should have limited scientific knowledge? I must have missed something, but I was sure "he" had the answers.
Also wondering how power is "pumped", oh well guess I'll believe you in that you speak with a basis of knowledge.

All the anti-expensive cord people overlook the one fact that makes these expensive cords sound different. First they start with the false assumption that current demand by the component is somehow constant? They argue that the original factory cord will deliver sufficient current for the component to operate as designed. That is the only thing they are right about. The sonic difference comes in the PC's ability to perform during extreme dynamic changes in the music. When the music changes, the current demand by the component changes. If you choke the power supply in any way or open it up, these changes will be audible by the average person. The music is not static. Test tones are static.

Gumby -

Could you be so kind as to identify whoever stated that current demand is constant - I've never seen anyone say anything like that, and it would be a ridiculous statement in any case.

But strangely, while you agree (correctly) that the original cord delivers sufficient current you seem to imply that it also "chokes the power supply". This seems inconsistant, to say the very least. Could you point out some specific components that cannot draw adequate current through the orignal cord? I'm most eager to find out which vendors won't spend the few dollars on a cord of sufficient guage.

By the way, how many people can identify different cords in a well-designed objective test (barring too-small cords or RFI issues)? In the past few days on rec.audio.high-end, a gentleman who generally falls in the so-called "subjectivist" camp scrapped an article on PCs because he could find no difference.

JHunter

Gumby, I would be willing to bet that in a better piece of equipment the power cord never sees the severe changes that you talk about. I do agree that the AC side of the supply does see changes in current demand but if there is sufficient filter capacity just after the rectifiers the greatest demand for power should only be when the amp is powered up. This is true simply because an uncharged capacitor looks electrically like a very low resistance.
Once the caps are charged, the demands of the amp are borne by the filter caps which in turn is charged by the rectified AC from your transformer and power cord. I think that a well designed power supply with a hefty set of caps renders the expensive cords impotent. I do however hear differences with different interconnects and speaker cables.