AudioQuest NRG-X3 Review (AC Power Cord)

[Ingenieur]

Yes, the argument was that the two graphs can not be the result of noise affecting the measurement of identical things. It would be impossible (or at least highly improbable) for randomness to conspire to plot these two curves based on measurments of identical test subjects. The difference cannot be explained away as noise. Since we don’t know anything about the test setup we simply have no idea what caused the difference.

First, not an 'arguement' but a position based on analysis.
Both plots are noise. Noise is random.

If run on the same device in a convoluted manner with ERROR/UNCERTAINTY added at each step and dealing with 30 uV levels no conclusion can be drawn. Only that inferring the null difference signal 'noise' or residual is due to the power cord is absurd.

The noise does not come from the power line. There are no 10,000 Hz harmonics in the power line and RFI is xxx kHz and xx MHz range.

The 50 Hz is not noise, it is interference.
Noise sources typically can't be identified.

The compared a 0.2 sq mm vs a 0.5 and their product is better. Why not compare a 0.5 to a 0.5 from 0 to 450 Hz? 9th harmonic. We know why.

 

[Ingenieur]

It happens all the time when I measure equipment and I vary for example, grounding. Sometimes this happens with which USB port I use to measure a DAC for example. Noise floor simply jumps up or down. In these situations, I don't use the setup for comparisons like cables. You have to first find a repeatable, stable platform and then vary one element, i.e., the cable.

Regardless, can we reach out to the company and try to get more detail? I could try to repeat their test. What is the cable they used in that test and how much does it cost?

The company is QED(?). They use a mineral sheathed cable. I don't see any power cables. Must not make a US version. Likely could not get that cord type certified.

Products

QED Cables - Made in the UK. Speaker cable, RCA cable, Interconnect, Subwoofer Cable, wire, cable, XLR, HiFI Cables and Accessories

www.qedcable.com

The paper

https://www.qed.co.uk/downloads/qed/QEDXT5whitepaper.pdf

Good Lord, just noticed this: they invoke the proximity effect. Lol
Who cares if R increases in a power cable?

 

[Ingenieur]

A couple of facts about the dreaded skin effect:
The only way to lower it is to increase DC R. As the skin effect factor goes up, L goes down, a good thing for audio.

Ro = R at rated temp, say 2 Ohm/1000' at 20,000 Hz
Correction factor X = 0.027876 sqrt(f / Ro)
Before 'accuracy' is called into question this is good for a cable up to 1.5 million CM

Using X = 2.77 you can find R/Ro from a table.
1.25 so R = 1.25 x 2 = 2.5 Ohm/1000'

How does L change? assume Lo = 0.19 uH/ft. From the same table L/Lo ~ 0.88
L now = 0.17
Xo ~ 0.024 Ohm/ft
X new = 0.021 Ohm/ft

Net Z per foot
Zo = 0.0243 Ohm
Z new = 0.0216 Ohm

Mother Nature giveth , and she taketh away.

 

[wwenze]

I wonder if you can claim that the cable stopped doing what it claims after 6 months of usage. Do these cables have warranty?

 

[DonR]

I wonder if you can claim that the cable stopped doing what it claims after 6 months of usage. Do these cables have warranty?

Like a reverse burn-in? My music now sounds veiled and the soundstage has collapsed? Even my wife noticed it from the kitchen?

 

[xaviescacs]

It happens all the time when I measure equipment and I vary for example, grounding. Sometimes this happens with which USB port I use to measure a DAC for example. Noise floor simply jumps up or down.

That's what I meant, there must be something else, not just random noise.

I've contacted the company, asking for more information about this test. They say from 2 to 5 days to answer.

We'll see...

 

[xaviescacs]

The company is QED(?). They use a mineral sheathed cable. I don't see any power cables. Must not make a US version. Likely could not get that cord type certified.

Products

QED Cables - Made in the UK. Speaker cable, RCA cable, Interconnect, Subwoofer Cable, wire, cable, XLR, HiFI Cables and Accessories

www.qedcable.com

The paper

https://www.qed.co.uk/downloads/qed/QEDXT5whitepaper.pdf

Good Lord, just noticed this: they invoke the proximity effect. Lol
Who cares if R increases in a power cable?

View attachment 196575

This is the power cable:

https://www.qed.co.uk/xt5-power-cable.html#tab1

Its about 180 €. @amirm, please consider not buying it until we have some answer from them to be able to replicate the test, or I would feel bad about it.

 

[Ingenieur]

Skin effect continued:
How to eliminate? Stranding
From the example above,
12 AWG, 2 Ohm/1000', 10 strands (not common, makes math easier lol)
Each strand ~ 20 Ohm, 10 x 20 // = 2

SE factor/strand ~ sqrt(20000/20) = 0.88 REDUCES skin effect, it, R/Ro ~ 1.0034 from 1.2, essentially no SE.
And since PE (proximity)
4 x (r/d)^2 x (R/Ro - 1) ~ the 1.0034 - 1 means it approaches 0, no PE.
Or 0.0022 in this case, both SE and PE
R = Ro x (1.0034 + 0.0022) ~ 0.55% increase

Next, why and when this matters.
Hint, not audio

 

[Ingenieur]

Now, why and when.
When: power, high power, not audio signal or power levels.

Why: assume R doubles due to SE. For the same I you have more Vdrop and power loss, which in turn heats the cable up 2x as much. If the insulation is rated 75 C, you are likely to exceed that and degrade it over time. The PE affect also may concentrate that heat in 1/2 the cable now you have 4X the power/unit area.

Oh yea, fried my power conditioner

I was using this to cool it.

 

[tungt88]

You had me thinking, the most exploitative industry is the fashion industry. My sister-in-law has run various fashion brands, initially as buyer, mostly teenage fashion. You'd be horrified how many fashion-concious teens work on minimum wage and save for months for some high-end fashion accessory or single clothing/shoe item. You then have disposable fashion, all their money goes on cheap junk that causes major pollution.

You really have to sell your soul to do that. I can't say I like her. The audio industry doesn't even come close.

p.s. Thanks for the first comment, because we did!

As you already know, the entire "Fast Fashion" business model of retailers like H&M, Zara, etc. are highly dependent on fast trends/social media (and they are multi-billion-dollar companies).
On a psychological level, the emotional need for confidence through "trendy" purchases is truly amazing.
But, that's enough from me. Back to the audio!

 

[tungt88]

But in Hans Christian Anderson's parable it was not his counsellors who told the king that his invisible clothes were a fiction, it was a small boy. Whilst the people saw the deceit, the king was prouder of his clothes than ever.

Well, every person is the "hero" of their own individual story, so there is that element of wanting to believe the illusion ... which is what folks like AudioQuest prey upon (classic psych games, like the Three-Card Monte setups, but on a higher level).

 

[DWI]

As you already know, the entire "Fast Fashion" business model of retailers like H&M, Zara, etc. are highly dependent on fast trends/social media (and they are multi-billion-dollar companies).
On a psychological level, the emotional need for confidence through "trendy" purchases is truly amazing.
But, that's enough from me. Back to the audio!

The reality is that whatever you think about these marketing practises, they aren't going to go away; and
Amir/ASR's arguments based on measurements isn't going to have any impact at all on the wider audio buying public. It's just one point of view shared by many members of this forum.

I saw that in response to Amir's numerous threads about the PS Audio P12, someone kicked off a pro-Amir thread on Pinkfishmedia, a very popular forum for your average audiophile. @Purité Audio spent a lot of time defending ASR's approach, but generally people aren't interested in a measurement-based approach and quite a few don't like the attitude either. One post seemed to sum it up: "My equipment would probably give Amir a cardiac arrest but then again, I actually listen to it."

I consider online gambling one of the biggest evils, but there husband of my wife's best friend runs one of the largest such business in the USA. It's not for me to judge him or people who gamble.

 

[voodooless]

The reality is that whatever you think about these marketing practises, they aren't going to go away; and
Amir/ASR's arguments based on measurements isn't going to have any impact at all on the wider audio buying public.

Got any numbers to back this up?

It's not for me to judge him or people who gamble.

Why not? You can judge whoever you like.

 

[amirm]

Paul McGown, CEO or PS Audio now says I don't know about testing power cables:

Incredible that he doesn't bother to understand the testing to know that I never used the cable to power AP. I was very clear in the video that it was NOT such a test. I used the AP to measure the transfer function of the cable. And I also measured the analog output of audio products (DAC and amplifier).

 

[amirm]

The reality is that whatever you think about these marketing practises, they aren't going to go away; and
Amir/ASR's arguments based on measurements isn't going to have any impact at all on the wider audio buying public.

You are quite wrong. I suggest you start reading the comments under the videos I produce. For the first time people are seeing comprehensive data backed by engineering explanation of why such things don't work to improve fidelity. This is far from arguments and shouting matches of the past. We are starting to make a difference here and the rate of change is going to keep increasing.

 

[Chrispy]

If you only let the marketers go about their nonsense in such regards, meh. At least we have something to point to when someone asks what these things do (or not particularly)

 

[voodooless]

Paul McGown, CEO or PS Audio now says I don't know about testing power cables:

Looks like he believes the propaganda his own spin doctors tell him Why doesn’t he fact check before posting more of this easily verifiable nonsense?

 

[amirm]

Looks like he believes the propaganda his own spin doctors tell him Why doesn’t he fact check before posting more of this easily verifiable nonsense?

It is very strange. You would think he would watch the video where I plainly say I am not doing what he says I am.

What I find amazing is that he thinks he is so much on the right that my results "can't be." He really, really has drank his own Kool-Aid.

 

[Rottmannash]

Smacking? Translation perhaps. I could care less about how a cable looks myself, and it isn't particularly hard to dress one up. Fraudioquest aesthetics I've not particularly thought much of in any case, or any of them....like I said it's not hard to dress one up if one wants to gaze upon it for some strange reason.

translation? If you haven't seen any news in the past week Will S literally walked up and smacked Chris Rock at the Oscars after CR made a questionabe joke about his wife's alopecia.

 

[Rottmannash]

At high volume, the speaker/air vibrations cause the copper strands to move ever so slightly and valance electrons in the adjacent copper strands shift enough to cause uneven electron movement (distortion) between the strands resulting in audible artifacts.

you should work for AQ...good ad copy.