Do powercords make a difference? A Test.


Well, I had this crazy idea that I could record the noise coming out of my speakers to evaluate different power cords in terms of noise reduction. Really simple and really stupid actually. I mean, if one powercord has more noise than another then maybe there's a difference.

I know a lot of people swear by the differences they can actually hear when adding an aftermarket powercord. And perhaps that's true, for some people. I have a hard time really telling the difference, though.

So here's what I did. And like I said it's really simple and really stupid!

I have a high end microphone and a USB preamp. I positioned the microphone tip like a half inch from the right channel tweeter. I then hooked up a basic powercord to my amp with no source components powered on. My DAC goes to a passive pre-amp and then from there to the amp. So I just kept my DAC powered down - no big deal, at least I think.

All I did was turn on the amp and record for about 5 seconds. I did this several times with multiple combinations. I tested a PS Audio Lab Cable, a Pangea AC-9, and the basic free cord we all have stored on a shelf somewhere.

So, what did I find? To my surprise you can actually hear the difference. But get this, the cheap power cord and the Pangea AC-9 are almost identical! I was not expecting that. And the PS Audio Lab Cable is by far the least noisy of what I've got.

I know this is not the typical way these cords are measured but how else can one really know what works and what doesn't? It's all about noise right? And the idea is to have less noise. Isn't that right?

Anyone else try this?
robpriore
I found out a long time ago that my amp sounded better plugged into a good wall outlet and not being filtered. I agree with you and think it would behove anyone that is filtering their amp to experiment just to be sure.
I've purchased a shunyata hi current power cord, about $300. The seller told me to plug this into the wall directly and then into my amp, thus bypassing my filter. I thought that was interesting, I mean I've always ran my amp through a filter, of one sort or another.

So while I wait for this new cord I go ahead and run my 15 or 20 year old exotic power cord from the amp direct to the wall. I do have an upgraded wall outlet: you know, cryotreated and specially coated. And a dedicated circuit to boot.

Then I do some A/B testing. I play a track, maybe ten seconds, then I shut down the amp and plug it in to the filter. I do this three times I think. I know it doesn't seem like a lot, I mean only three times? The difference was so profound I didn't need to keep testing. I was pretty shocked, and frankly felt stupid for not trying this a long time ago.

The long and short of it is plug your amp directly into the wall. In my case, my filter is doing just that - filtering. Take the filter away and it's like the room just got bigger.

I'm certain this configuration is better. At least for my setup. I'll keep testing it, there may be some higher frequencies in there and maybe over time I won't like that.

Anyone else experience this?
I'm not sure noise is the main point of a power amp cord. ITs more about ability to deliver current efficiently with a power amp.

For source level gear, digital ones in particular, noise levels are a much bigger issue that a power cord might help address.

Pangea ac-14, not ac-9, is the model designed for digital/line level/noise applications, whereas ac9 is more about the current delivery for a power amp.

Its better to consider how cord designs are different to address different issues at hand (noise levels in source gear and pre-amps versus current delivery for poweramps) rather than assume all power cords are designed to solve the same problem in the interest of better sound quality.

Also, in the case of noise levels, noise issues are likely not merely just more harmless random noise that might be detected separately from the musical signal, but rather more structured, non random, forms of noise at certain frequencies, etc. that might be more difficult to measure and distinguish yet have a more detrimental effect on the sound by introducing specific distortions. A good pair of ears probably have a better chance of detecting a difference than any measurements, unless the noise/distortion is quite significant.

Of course its very hard to communicate and bank on what one hears in any particular case, so the results may never be reliably reproduced by others.

I think the key is to collect enough data points from many distinct test cases by many users over time to be able to discern anything conclusive about these things. There is statistical power in numbers that a single case or even a larer set of uniquely biased cases can never achieve.
I have a dedicated circuit in my board for the audio stuff. I use an MIT plug receptacle. So it's pretty well controlled. I mean, the fact is the cords sounded different. And the PS Audio was quieter. So I use that as the primary now.
Research and read everything you can find about how Caelin Gabriel of Shunyata Research has approached this subject. Here is an interview done by 6Moons: http://www.6moons.com/industryfeatures/caelin/caelin.html
It seems the ability to analyze the effect of PC design demands a bit more than what you suggest.
It certainly is not just about the noise. Power cables have an effect on other aspects of the sound as well. Not to belittle your experiment... it's very interesting. But, you are only comparing one criteria by which we judge cables. I'd gladly take a little noise along with a great sounding cable, rather than a quiet cable with lesser sound.
Blue Circle audio has been doing something similar for years for their power conditioners. There's a youtube video where they demonstrate the effectiveness of their power conditioners. https://www.youtube.com/watch?v=Noc2OA-xWCM.

It's conceivable that one can take that "noise sniffer" and plug it into various power cords to hear which one "sounds" best but I doubt that any power cord, by itself, can sound as clean as a power conditoner. In fact, the better cords just may sound worse. It would be nice if someone tried it out.

All the best,
Nonoise
I liked that approach. You can also analyse plots visually if there's a software to it.
I don't deal with aftermarket powercords because I simply believe that it's a marketting scam more than science or research and prices are not justified regardless of weather there's a difference or not.
I think you should patent the idea and sell it as an audiophile tweak for several hundred dollars. Come up with a catchy name and you may well be able to make enough to retire early.
I like the way you think; however, in theory a significant part of how a power cord can perform given the power demands of the music. You may be onto something for sources and such, but you are missing a big part of the picture for amplifiers.

I can hear my Apple AirPort Extreme through my tweeters when using my tube amp. Are you certain that nothing else was effecting you tests?
IMO, all that matters is how the music sounds with the various power cords.