For 6 years I shook my head at power cord sillyness. None of the physics I knew could explain a difference and on a whim I even tried swapping a few stock cords to see if there was any difference. None. At the time I had a Krell integrated which had very harsh high frequencies, and in an attempt to 'equalise' them I borrowed a different interconnect or speaker cable from the local store, every week for months.
Some made no difference while others made a noticeable difference but there was no correlation to price, but none removed the congestion and harsh treble of the Krell. I even tried three different sets of speakers. After deciding to replace the Krell I thought I should optimise the rest of the system and update it. After reading again about power cords I borrowed some to try. In one session I tried the CDP with a digital cord (foil shielded disconnected from equipment end), a high gauge cord for the amp, and what the hell I'll replace my wall outlets with a more robust inexpensive 15A socket so I could have two outlets, and I tossed aside my cheap surge supressor power board I was using.
With no other changes apart from these, the audible difference was greater than any non component upgrade I have heard in 25 years! in fact the difference was bigger than many different speakers or amplifiers upgrades. All of the congestion was gone and the treble was very sweet. It made me realise the Krell was a fantastic amp, after years of owning it.
I was an instant convert and dont pretend to know why it made such a difference but it did. There are a few suggestions as to why.
*Standard 18awg cord is really only rated for 2.3A and even at that it attenuates current - the cable from the power station comes in on 11awg cable, try and keep at least that gauge through to your components, especially to amplifiers.
*Ideally the cable should be twisted to reject EMI
*Every connection, especially cheap, loose domestic plugs degrades the signal. Connections chatter and create RFI - firm tight connections are best , and try to minimise the number of connections (switches, plugs/sockets)
*Your TV, CD player, wireless network connections, computers all generate RFI (which affects the way DACs decode) and create a 'digital' harshness in the treble. Your household is a potential RFI swamp and the 2m powercords are like aerials pumping this RFI into the power supplies of the components. This mainly affects digital sources like CD Players, DACs and receivers. Now with Class D amps these are also affected by RFI. The solution is that for these is to use shielded power cables with the shield 'lifted' (disconnected) at the component end. Wiring two high voltage capacitors across the live and neutral also helps filter out this high frequency garbage.
*Avoid cheap surge suppressors on amplifiers. A surge suppressor was killing my Krell performance. Unless the surge suppressor / power filter does not limit current (rare) then avoid using on amplifiers and reserve it for the front end components.
As with many people my high-level understanding of electricity gave me preconcieved ideas, and my initial experimentation with similar stock cords yielded no discernable results. But one of the axioms of science is that theories, laws and rules are made to explain the observable phenomena, not the other way around. Just in the same way that Quantum Physics explains many observable phenomena that Newtonian Physics cant. Just the same way that our observations of the way gravity interacts with matter over long distances (the Voyager probes) is indicating that Newtons laws are not quite right and are giving rise to Modified Newtownian Physics. Im sure that all of the scientific understanding is already there to explain the audible differences in power, but there is no real monetary reason to pour large amounts of R&D money into this area.
Keep an open mind. But also stay rational, spend money on components first, but dont ignore power, and simple low cost things (beefier wall plates, fewer connections/switches, shielded power on front end, high gauge cables on amps) can make a surprising difference.
As others have said, start with the Volex 17604 Cords for about $12, they are both foil shielded and higher gauge (14awg), you may not ever need anything better. Now that I am tweaking further I am slowly replacing these with more customised DIY cords.
