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Why an AC Power Cord cannot make a difference

The best tests were done with "golden ears" persons that are persons that are real melomanes and go to concert nearly each week.
What you really mean is trained listeners;


JSmith
 
@pma

You should do fuses next. I have been surprised over the last four years that some people will pay upwards of $100 dollars for an "audiophile" 5x20mm fuse and swear it makes a difference. I always try to talk them out of it but usually get the "some things just cannot be measured" response...
 
@pma

You should do fuses next. I have been surprised over the last four years that some people will pay upwards of $100 dollars for an "audiophile" 5x20mm fuse and swear it makes a difference. I always try to talk them out of it but usually get the "some things just cannot be measured" response...
But.. It has more speed and better 3D !
I tried to select the slow blow but it still has more speed..

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I agree that a lot of power cords are not efficient because they do not work to cure the pb of EMI and RFI activated by the power cord itself. I work with many manufacturers of audio gears (very famous) that do not believe in power cords. I made some demonstrations with on of them, may be the most reluctant about PC action. After a long explication why PC could not work (He is Engineer in electronic and designer of probably the best amplifiers), I (engineer too but mainly in acoustic and mechanical vibrations, formerly professor in a University) made a test : blind listening with standard power cord of his famous amplifier and then with a highly regarded power cord that ASR say he could not work. All the people in the room said the second listening was vastly better! collective hallucination? electric compensation of ...? In fact I know why it's better and yes I agree 90% of PC change the sound but not improve it, but some do. I also made tests (blind) with audiophiles and same result. I conducted finally the same test with skilled musicians, same result. Some PC improve music playback and not only change it for a different taste.
The conclusion: as a scientist I always try to find why and how a phenomenon occurs.
This is the same subject that power conditioners. 95% do not work well because they wrongly "depurate" 230V. 230V should be perfect sine wave with no deviation with no harmonics... even if some electronic power supply make a very good job to filter AC at the input and they store energy. Only hearing transformers "singing" without music because there is some DC or too much pollution in AC that the power supply could not treat enough. This time too, proof is in the listening.
Scientist approach is mandatory but it should be well done and not conclude to wrong judgments due to inappropriate measurements (I spent 10 years making measurements).
Any statistics involved?
 
The best tests were done with "golden ears" persons that are persons that are real melomanes and go to concert nearly each week.
Going to concerts or being a musician dosnt mean you have golden ears. Actually many musicians have hearing damage and what they hear is not what the audience hears. A trumpet does not sound like a trumpet from the mouthpiece.
 
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Going to concerts or being a musician dosnt mean you have golden ears. Actually many musicians have hearing damage and what they hear is not what the audience hears. A trumpet does not sound like a trumpet from the mouthpiece.
In fact probably the opposite!,

Concerts are very seldom "optimal" in sound quality , I know back in the day I remember to come home with a beep in my ears for several ours after, but perhaps i listened to too many metal and hard rock back then:), your tastes or mileage may vary.

edit, sorry i now see that this comment should have been addressed to PHP
 
A power cord must also change the image of a projector, television, VCR, Blu-ray player and the performance of a computer or an electric saw or makes coffee better.
Since amplifiers, preamplifiers and DACs all sound the same, it will be harder to hear a difference unless there is a cognitive bias.
Almost 40 years ago, we listened to speakers without knowing which ones worked and unanimously, we didn't find any bad ones, even things made by beginners...
 
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I don't think anyone noted that the stupidest wooers call them power "chords." A Freudian slip alluding to what they're not capable of doing
 
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I have an amplifier that keeps playing after the power switch is turned off - for many seconds, depending on the volume of the material being played - higher volume shorter play time.

I could swap power cords without interruption, which might make for an interesting listening test scenario that I won't perform.
You have storage capacitors in the amp that store enough energy such that after shut down, they can power the amplifier for a few seconds before they run out of electricity. The louder you play, the faster they drain.
 
I apprenait interesting comments even on contrary to what we clearly observed. An experimentation is done with exactly the same parameters is right, whatever is the finding, not the conclusion.
I had answered about my knowledge and my 30 years of science and engineering.

Sorry volks, but you know my schtick, I have to do this.


And various other fallacies... :D
 
no. I do not use a sequence nor have all the listeners at the same time to be sure there was not influence by some words or....
Anyhow, my intervention is to give an experience not to speak endlessly on it.
The only thing I can say, it's that I prevent to test with "basic" audiophiles because they judge by assimilation to audio habits and not with unamplified music as reference.
This was also a statement for myself as I have audio manufacturers different voices on the sujet of PC.

The way you approach the subject indicates you would be happier participating in Audiogon or Hoffman
 
It happens when the vertebrae slide forward, backward or sideways over each other.
The discs between the vertebrae get ruptured, allowing bone-on-bone contact of the vertebrae and possible impingement of the nerves in the area. Consequences are severe. (I'm not a doctor).
 
The occurrence of such called "listhesis" is very rare, and a severe damage of nervous structure are even more rare,
excluding explicitly the traumatic causes.
 
The discs between the vertebrae get ruptured, allowing bone-on-bone contact of the vertebrae and possible impingement of the nerves in the area. Consequences are severe. (I'm not a doctor).

I am. Your explanation is correct. Also, the discs can herniate into the nerve foramina and cause impingement.
 
You are, me too, and we do not want to emphasize, not?
 
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