Blind Power Cord Test & results

I agree with Ohlala. I think the way to test A vs. B is to try to detect differences, NOT try to identify the sound of A or the sound of B. IOW, blindly and randomly compare 2 power cords together (AA orAB or BB) to see if you can discern a difference. Your response will be : Yes, there is a difference between the two or No, there is no difference. Repeat this random pairing 10 times and see if you could detect differences when the pair tested was indeed different(AB) and see if you were correct identifying when a pair was indeed the same(AA, BB). If the results were close to 50%, then you could not detect a difference between the 2 PC's. This way you are not required to know the unique sound of A(or B) intimately enough to identify it right away. I'm not sure this makes the testing anymore valid but I would think it should make it easier to do better than chance. Subsequently, if a difference can be discerned between 2 PC's then you can try to decide if the difference was significant enough to justify any price differential. Also you can decide which PC's sound you prefer and why. This can be ascertained with long term listening tests.

Jayarr said:

the way to test A vs. B is to try to detect differences

I agree insofar as this would be a FIRST objective. Ultimately, a testing would (should) lead to choice since, at the end of the day, a) it's a market & b) we invest in (meaningful?) "improvements" -- or not at all!
HOWEVER, cords seem extremely difficult to test with the "quick succession testing method". You have to power down, change (some PS's will lose juice in the process), power back up and listen immediately -- in order to power down again, etc, etc. I'm not sure there is time enough for the "repowered up" system to reach sufficient operating/ resolution status to easily gauge differences -- or none...

Having said that, I had ONE such successful experience. I use TWO amps and happened to change cord on ONE of the two. On power up, the amp played lower (amplitude) than before. Did it again, same thing. Kept the amp powered up for ~15mins with the cord under test -- no cigar.

Subtracting the "blind", audiophiles essentially ABX everything they try in their system. While the hometheaterhifi experiment has problems affecting its validity, these problems are not inherent to ABX. Two factors that apparently people seem to be implied with ABX are time and stress. Time does not have to be a parameter, really. It could be a factor with this experiment - I think the training was too short, but it does not have to be. Although stress is typically not the significant contributor people think it is to cognitive tests, it too can be varied (and tested if one wants). What I would want with an ABX test for PCs is to mimic home trials, without revealing the pc models. That has practical difficulties, but...

Another problem with this experiment is that there is no real hypothesis and barely a conclusion. This subject is difficult to discuss when people are coming up with wrong, overly broad and multiple conclusions. There is only one conclusion per variable which includes the conditions of experiment, and there should have been a distinct hypothesis to eliminate the BS. The hypothesis determines the test procedure...there is no general best way. While the experiment was a good exercise, it was too flawed, imo, to support whether or not "pcs make a difference". Plus no one experiment can yield such a sweeping conclusion. Other factors can be manipulated that could affect the results (that is why I stated the conclusions must include test conditions).

PS -

"Some people can hear the differences and repeatedly get them right, while some people can't."

"There is so much psychological stuff at play here that we can't tell if the differences are real or imagined"

These are not factors after decent sampling, and statistical analysis.

I have experimented with several power cords over the years spanning the price range from $100 to $3000 . I have observed that all of these cables irrespective of pedigree require some "settling time" of up to several hours to sound their best. Consequently, I think that PC cable evaluation can be very misleading under the conditions of "double blind testing". In my system I can easily hear differnces among some cables.

Perhaps misleading if you are trying to choose which you prefer. Less so if all you are trying to do is detect the difference. When I make a cable change at home, I can hear a difference right away. A day later, I sometimes feel differently about the difference I am hearing.