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Power cord blind test

diegooo1972

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@Hypnotoad This is exactly what I expect.
And if you can't prove that it sound different but no one can ear that difference the point is taken anyway.
And this is just what science approach sais.
It's really amazing that people think to hear more then a professional digital oscilloscope in good hands.
 

FrantzM

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Methinks you invest too much electrons in this discussion. The test is rigged and this is all that needs to be shouted about it: FRAUD!
 
OP
D

Dimitrov

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Okay guys, he redid the test after I complained about the channel imbalance issues, so here is the new video :


Can you please check to see if the levels have been changed again? I don't want to leave this guy off the hook!
 

Hypnotoad

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I am listening through my PC onboard soundcard with AD700 headphones and can honestly hear no real difference between them. Even though it says there is a peg on the singers nose, I can't really hear any difference. He's making it up as he goes along if you ask me.
 

solderdude

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It is still a sighted test... You are told what is what and see the cable in front disappearing.
You are also told what you must be hearing (otherwise you're deaf).
The sound quality is still very poor Youtube quality.

I recommend to take the 'test' without simultaneously LOOKING at the video first.
Use ears only and listen using revealing gear.



disclosure: I listened using EQ'ed HD800 and like @Hypnotoad hear no difference, at least when NOT looking at the video 'hints'.
I'll repeat... the youtube quality is really VERY poor.
 
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diegooo1972

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WEBM 160abr is the best quality stream you can't take from this youtube video.
WEBM 160abr is never enough to get something out of any youtube high end comparison.
Only with speaker you can hear some differences and sometime help you a litlle assuming that 2 great microphone are used and the room is decent.
Adding gen to the link www.yotube.com like www.genyoutubecom you can see all the possible format audio and video you can download.
So that in this case www.youtube.com/watch?v=G_QVHbo-nJ4 became https://www.genyoutube.com/watch?v=G_QVHbo-nJ4
Downloaded. Now i go where the difference should be and see if it's modified.

update
To begin with in both A and B recording there's a click you can easily hear between 00:02:28:690 and 00:02:28:694 in track A and between 00:03:06:850 and 00:03:07:050 in Record B. Just faulty track ?
Well in case of faulty track this the biggest noob comparison I've ever seen.
 
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VMAT4

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They definitely sounded different to me. So I downloaded the video and extracted the track in my audio edior. Here is the outcome:

View attachment 29553

As you see in the Left channel on top, the level suddenly drops with "the other cable." But nothing like that happens in the other channel. So either through mistake or on purpose, there is a problem with the capture of one channel. No way a power cord impacts one channel this way.

Darn Amir, you found a measurable difference! Here I was debating, after I heard "A" sound better to me, how long of a cable should I buy?
Where should I located my system in my house? If one meter of expensive cable sounds good would two meters sound twice as good? Should I locate my system far away from the breaker box and run power cords to a power outlet near the breaker box? Oh my! Now if only I could get Metropolitan Edison to use "good" and "proper" wire for their distribution system! And who knows how substations could be improved?
 

JohnYang1997

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Darn Amir, you found a measurable difference! Here I was debating, after I heard "A" sound better to me, how long of a cable should I buy?
Where should I located my system in my house? If one meter of expensive cable sounds good would two meters sound twice as good? Should I locate my system far away from the breaker box and run power cords to a power outlet near the breaker box? Oh my! Now if only I could get Metropolitan Edison to use "good" and "proper" wire for their distribution system! And who knows how substations could be improved?
Just get a reasonable priced thick gauge cable. Also it depends on how much power you need how loud you normally play. If you regularly cranck up over 100W 300W sure it may be a good investment (not the expensive ones). Also cable making difference is an indication that the amplifier is not well designed.
Many PCs have power of hundreds of watts. There shouldn't be issue on power delivery capabilities.
 

solderdude

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It would be extremely easy for cable manufacturers to actually put an oscilloscope on the rectifier caps and log the rectified DC voltage of a 1kW power amp (or more realistically a 100W amp) and show the difference in voltage sagging with music content under max load with 2 different power cables and everything else being the same.

The reason why we never see such irrefutable evidence like this is rather obvious... and no.. it's not because no one thought of this.
 

JJB70

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If people don't believe that equipment manufacturers are capable of figuring out the right power chord to ship with gear why would they believe that the same manufacturers are capable of doing the difficult bits of equipment design and manufacture? And why would you buy anything from a company that you believe is incapable of getting something as simple as a power chord right? My experience is that the power chords outlive the rest of the equipment and I occasionally have clear outs where I take surplus chords I have accumulated to the recycling centre to stop them cluttering the place up.

I believe the technical term for the chap posting this video is that he is full of ***t. Not that I want to be judgmental or anything.
 

digicidal

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If people don't believe that equipment manufacturers are capable of figuring out the right power chord to ship with gear why would they believe that the same manufacturers are capable of doing the difficult bits of equipment design and manufacture? And why would you buy anything from a company that you believe is incapable of getting something as simple as a power chord right? My experience is that the power chords outlive the rest of the equipment and I occasionally have clear outs where I take surplus chords I have accumulated to the recycling centre to stop them cluttering the place up.

I believe the technical term for the chap posting this video is that he is full of ***t. Not that I want to be judgmental or anything.

That's always been my question, especially in light of the fact that the ones hawking luxury accessories often present the 'justification' as being tied to the highest-end gear. So we're to believe that the manufacturer of a $50K amp is able to build one that is fundamentally superior in every way... yet somehow incapable of designing it to work with the power you have and the cord they supplied. Or alternatively, is incapable of designing a better cord to go with it - which seems like a much lower hurdle to me. Especially since the 'pedestrian' brands and models seem to be able to pull this off to a reasonable extent.

I guess the real geniuses of engineering all work for Shunyata & similar... it's just a shame they don't design components as well. :p You could probably get a DAC with a chassis made from special noise rejecting stones and cryogenic treatment for every bit that goes into it and note that comes out.
 

watchnerd

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I have invested in hospital grade power cords for my system:

hosp-5-15p-full.jpg


They offering the following benefits:

-Color match my gray Blue Jeans / Canare speaker cables
-Color match better to my floor and baseboards than black
-Don't jiggle in the socket
-MOST IMPORTANT: they're too hard for the housecleaner to pull out of the sockets for hooking up her vacuum. Nothing worse than coming home to finding the system unplugged or a subwoofer unpowered

Yes, they're a bit of a splurge at $8-$12 each, but I'm worth it.
 
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digicidal

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Too bad they don't come with nylon sleeving on the cord - that really helps get those blacks even blacker.
 

typericey

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Okay, so we all agree that spending $$$ on an aftermarket power cable is stupid.

But does the IEC power cord that came with your amp, DAC, etc. adequate? If not, what would be a sensible replacement? What is the Blue Jeans or Mogami of power cords (if such a thing exists)?
 

Hypnotoad

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But does the IEC power cord that came with your amp, DAC, etc. adequate?

Since I couldn't tell the difference between a stock power cord and one costing thousands, just use the stock cord and save your money, IMHO.
 

watchnerd

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Okay, so we all agree that spending $$$ on an aftermarket power cable is stupid.

But does the IEC power cord that came with your amp, DAC, etc. adequate? If not, what would be a sensible replacement? What is the Blue Jeans or Mogami of power cords (if such a thing exists)?

Hospital cords.

See above.
 

digicidal

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Okay, so we all agree that spending $$$ on an aftermarket power cable is stupid.

But does the IEC power cord that came with your amp, DAC, etc. adequate? If not, what would be a sensible replacement? What is the Blue Jeans or Mogami of power cords (if such a thing exists)?

I'd say that even considering the cord for anything other than an amplifier would be ridiculous. Nothing else in the system should be drawing enough current for it to matter. Even the cheapest amps I've purchased (Crown XLS) came with a nice, beefy free cord - didn't say but I'd guess 14AWG at least - it should be a non-issue for everything else.

Well, if you want to pimp it out, you can always add your own Techflex:
https://www.techflex.com/news_announcements/tightweave-new-colors

Yep... that's what I put around the speaker cables I made... and they look right at home next to high-priced jewelry cables IMO at least. Problem is it's not nearly as easy to sleeve without modular termination (cleanly at least). But if that's the desire, it can still be dealt with for (at most) $30-50 per cord. Still won't sound better though.

Thanks to China/Ebay... it's even cheaper to get the looks (although I'd probably test first to make sure it wasn't miswired by the sweatshop). Still totally unnecessary... but look every bit as good as the ones tested in the videos linked in this thread IMO.
 
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STUDIO51

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The power cable of my APx555 is not much different from that of a regular PC's. In fact it looks the same so it's already mixed with other IEC cables.

However, the AP self test still shows the same performance. Even if you change the polarity of the power cable.

Some lab connect the APx555 to a very expensive AVR + UPS. However, the difference in performance is insignificant within the error range.

Well designed devices are not sensitive to power quality. If you have a device that really changes the sound by replacing or change polarity of the power cable, you should doubt the design of DUT.
 

Wombat

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I have 15 or more audio items in my system with power cords. Just thinking about the cost ................................... .
about-to-vomit.gif
 
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