Power Cord Length


Here's one for the electric wizards to kick around. Whilst attending Axpona this weekend I was doing some power cord shopping. At one particular display I was being told by a very well known cable company representative, I'll not mention the name so it doesn't influence any responses, that the rule of thumb is that in order for the pwr cord to be effective it needs to be at least five feet long. This allows the current to be in the cord long enough for it to be effective. Ok, I'm really dumb when it comes to this sort of thing so maybe I said that in the most simpliest of words but that's pretty much how it was explained. Anyone care to elaborate on this good or bad?
Ag insider logo xs@2xjackcoke
I love how people who have never tried "fancy" AC Cords are so sure they cannot make an audible difference. I hate that they do indeed make quite a difference in most cases but they are terribly synergistic and it is difficult to recommend any one overall. Just the stiffness of the local electrical grid can be quite a factor as well as the associated equipment (and appliances) on the same lines. Damned if the ac outlets themselves seem to affect sound too.
 One poster is right on the money. They are indeed a parasitic element to the power supply. They can be designed as filters (or include filter networks), used for current or voltage storage and at least one claims negative impedance while others claim shielding makes the difference. Then there are those who claim they act as a transmission line so the geometry and dielectric matter there. Different metals, conductor shapes, and terminations also seem to have their own effect. Resonances (all finite length conductors have) based on length and propagation speed can be seen with an oscilloscope and frequency sweeps or a network analyzer. There are mechanical vibration and microphonics to deal with; even static charges are dealt with in some cases. Wire loss or DC resistance is a fact in any case and varies with frequency.
 Regardless of explanation or principals whether or not it is audible to you should be the criteria. We just do not know it all and our system of measurements are quite limited and lacking IMHO. Find a friend and try some blind testing if you can. Mixing and matching is part of the art.
 It must also be said that many designers are not going to give away their particular paradigm or trade secret while others do have white papers and measurements galore it is a complex issue. Ultimately it is your own listening judgement and I urge you to try experimenting. The  relatively inexpensive DH Labs bulk DIY cable is a great place to start.
WOW! I will now return to the ADULT world, goodbye

Don't let the door hit ya where the Good Lord split ya!!
 
It must also be said that many designers are not going to give away their particular paradigm or trade secret while others do have white papers and measurements galore it is a complex issue. Ultimately it is your own listening judgement and I urge you to try experimenting. The relatively inexpensive DH Labs bulk DIY cable is a great place to start.


No, it's not a complex issue.  A power cord is a very simple issue. Building an actual power amplifier IS a complex issue.  Power cords, speaker cables, etc. are not complex at all.

What is really complex is our brains and the physiology of our acoustic system and perception.  Every time I have a couple of beers my system sounds so much better. 
I did research and bought a spool of Belden 19364 wire. This wire is 14ga, shielded with a drain. I bought good plugs for the ends. I did research how long the wire needed to be to not let the cycle length of the electricity exit the cords and pollute the rest of the system. I think it was 4' or so, I did this a year or so ago. I plugged them into my monoblocks for a listen and was very presently surprised. Before this I had used computer power cords that I had on hand. I also use a power conditioner, so I changed out that cord a week or so later and heard no difference. I've played around with different interconnects and speaker wires as well. Some wire leaves me flat others make life grand. If you are a person that can hear no difference it is you or your gear. Top end equipment that has the ability to provide your ears with frequency beyond your hearing limits provides subliminal spacial imaging as well with proper harmonizing cables and cords.