Measurements are liked in this DIY Audio site, so in this video could this measurement account for some of the difference in the way power cords sound to some people?
From your description I would say it seems pretty high end to me. Maybe not the ultimate high end, but clearly not all off the shelf consumer grade.
Now you know, when we argue if something can be heard or not, it is not my system limiting me. I’m deaf as doorknob. 🤣
Actually what you are thinking about is the:
GEC : Grounding Electrode Conductor system. The 25 Ohm method is one option, but it requires expensive equipment and electrician time. The most common option is 2 or more ground rods but there are other options.
While the Safety Ground system has continuity to the GEC system, it is a different system and has a different primary function.
I see this as a nice demonstration of Ohm law and another misuse of proper measurement instruments for marketing purposes.
Dynamic Transient Current Delivery is nothing more than short circuit current determined by power cable + power line resistance. Power cable resistance is typically 0.05 - 0.2 Ω and with 120 V that yields exactly what was measured. Cable to power socket was very thick and with about 0.1 Ω resistance.
Most important question is why and by what physical mechanism, would 01 - 0.2 Ω change at mains supply, affect amplifier performance?
Power cords sometimes act as distributed filters. Depends on construction details. That said, 'Dynamic Transient Current Delivery' at audio frequencies may not be right explanation. There was a case where a preamp was found to be sensitive to power cords. The fix was to fit it with filter at the AC line power inlet.
They say that the greater the resistance and impedance of the power delivery, the longer it will take to fill the main filtering capacitors in the power supply. This means that the rectifier diodes will be conducting longer and allowing power line noise in longer. That is what they say.
Yes, but we need to look at the time constants involved and how much energy can be stored in a power cord structure. Things like that. A few microseconds (if that) discharge of stored energy probably isn't going to make much practical difference charging up some big ol' power supply filter caps. More likely if there is a difference in sound, the actual underlying causal mechanism isn't the one being proposed.
Most of us here know that the "code" refers to US national electrical code. However since this is an international forum IMO it would be advisable not to discuss national regulations as the "code" is not the same in other countries.
This is the proper and very important example. I’m probably a nonbeliever in sound of power cables because my system is immune to power cable changes. I can’t hear or measure anything of significance. Though, I use power inlet modules with filters and ground loop breaker circuits, along with audio grade transformers (static shields and Gauss bands) and regulated power supplies with decent PSRR.
If my audio system would be sensitive to cable changes, first question I would ask myself would be “What is wrong with my system?”.
Well in a word, no.
Meaningful filters of power line harmonics are very large indeed.
Note that while it's a very rare problem, AC power cords can act as interference antennas (both receiving and more likely transmitting). In those few cases, changing the length or placement of the cord can change the problem.
I was just replying to another member's post.
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But the point I was trying to make is that in most US homes the resistance from the Safety Ground to Planet Earth thru home's Grounding Electrode Conductor system is often much higher than 25 Ohms.
But for day-to-day AC power quality, the connection to Planet Earth doesn't matter. It's there for safety during dangerous situations.
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It is most certainly not the right explanation. Power factor has more to do with power delivery than any current issues in average audiophile appliances.
A resistive cable would be likely to deliver better power in an AC environment but it would have to be tailored to each device. It’s simple, the best power delivery comes from the least likely to saturate the device in any way, while maintaining voltage to not produce inconsistent sag. All the luck in the world with marketing that though…
You may have seen a certain video by someone who tries to measure a power cable’s effectiveness with low level signal, by waving it around other gear. That was comical… proximal pickup is almost non-existent for audiophiles (barring perverse ground issues and certain phono products that he wouldn’t even use). Now if he had measured it as an inline filter and not a shield we might have learned something.
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Which means it’s even more worthless as the world’s supposed proverbial toilet for the baddies.
As in the tie to neutral is the only part probably doing much of anything.
https://shunyata.com/2016/06/27/power-cord-misconceptions/
I want to be clear, I do not work for Shunyata, or have ever bought any of their products. I am only linking their information because they talk about their products with some degree of technical information included. If anyone knows of another company or source of power cord information with technical data included, please let me know. Thanks.
Hundred years ago there was no agreed standard for notes. A4 actually ranged from 415Hz (or even lower) to 466Hz depending on who, where and when you were (Bach used 466Hz).
That only changed in 1926 when the USA insisted on using 440Hz but not everybody sticks to that either: US (except the famous ones) and UK orchestras tend to use 440Hz while European ones tend to use 442 or 444Hz.
So if you hear a tone in isolation it is pretty much impossible even for those who have 'perfect pitch' to say if it is sharp or flat. It works only in relation to other notes.
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