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GR Research B24 AC Cord Review

Rate this AC Cable

  • 1. Waste of money (piggy bank panther)

    Votes: 336 95.2%
  • 2. Not terrible (postman panther)

    Votes: 4 1.1%
  • 3. Fine (happy panther

    Votes: 1 0.3%
  • 4. Great (golfing panther)

    Votes: 12 3.4%

  • Total voters
    353
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amirm

amirm

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Um, yes. It does stick Amir...

Do some basic differential ground/earth tests on various circuits/loops in your house and report back. Ground potentials vary massively- even on a simple circuit.

Just measured a ~2.0V ACRMS ground/earth delta on a 1200W (heater-PF 1.0) loop from one GPO to another. Maybe 10M max- one room to another.

Just like when you measure amplifiers- when did you last clarify and specify the line voltage? Hint: it make a big difference, especially with linear supplies.
You are arguing my point, not his. Said differential in outlets would never be cured with a 6 gauge ground wire in AC cord as Tom claimed. Indeed I quoted papers indicating differentials on outlets.
 

DualTriode

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And by doing that your reference is no longer at zero so you have to do gymnastics to interpret your results. All the peaks are now relative to -20 dB whereas mine was a much more convenient 0 dB. Any time I see someone post graphs like this, I know it is guaranteed that people will read the incorrectly, not realizing the reference not being zero.

There is a reason dBr (relative dB) was invented. It was for precisely this problem. You dismiss it and brag about it?

You are mistaken. Everything on the FFT plot is referenced to 0 dBV which is 1 Volt.

If you use dBr and reference everything to dBrA without noting the test voltage then other things become completely undefined.

If we look at the 1000Hz test peak on the FFT we have no clue what the actual test voltage is unless you tell us. With no clue what the test voltage is, dBrA is just floating there in the sky.

Now if I look at the power supply harmonic series in the FFT, using dBrA without the actual test voltage I have little or no idea about the power supply harmonic peak voltages. If We know the power supply harmonic series voltages we can have a very good idea if the power supply hum and buzz will be audible or not.

If you regularly do a few of these FFT’s with a dBV scale you will develop what I call eye brain coordination and even be able to pick % distortion from the plots as well.

As I suspect you will continue to use dBr, please note the reference voltage, we can do the feigner counting to place the peak voltages on the graphic.

While we are on the topic of dBr, most often dBr is a relative voltage measurement into a constant impedance. SPL is an acoustic measurement and is several variables and calculations removed from voltage.

dBr SPL is apples, dBr Volts is oranges, they should not be on the same graphic without an explanation of the cognitive leap.
 
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amirm

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You are mistaken. Everything on the FFT plot is referenced to 0 dBV which is 1 Volt.
So how come you can do an FFT on a music file? Where did the voltage come from there? Can you put a multimeter on your music file to measure its voltage?

FFT operates on digital audio samples. Said samples have no voltage associated with them. How could they when I can play the same file at 1 watt or 1000 watts.

Of all the things I have read in this thread that are wrong, yours just became #1.
 
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amirm

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If you use dBr and reference everything to dBrA without noting the test voltage then other things become completely undefined.
Oh really? So if I referenced everything to 1 meter, you are claiming all my measurements are meaningless? 0.1 meter in not 1000 times smaller than 100 meters? Where do you get this knowledge? Fortune cookies?
 
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amirm

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If we look at the 1000Hz test peak on the FFT we have no clue what the actual test voltage is unless you tell us. With no clue what the test voltage is, dBrA is just floating there in the sky.
You have a clue if you can read:

index.php


The reference is clearly stated: 120 dBSPL. Any spikes below then is relative to that. Once you hit negative dB relative to that, i.e. below 0 dBSPL or thereabouts, you are below threshold of hearing.
 

Lambda

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The reference is clearly stated: 120 dBSPL
Your not measuring SPL do you? You measure voltage. You don’t tell us the amplitude of your 1kHz test signal. Why?
It mattes because Noise is constant (independent from 1k signal amplitude) but signal amplitude is not. it depends on the signal level chosen by you.

Signal to noise ratio is in this measurement is about ~110dB. if your 1khz signal amplitude would be (for example) 50dB lower the signal to noise would only be about ~60dB.

even if the 1k test signal would be 50dB lower (electrical) you could still define/reference it as 120dB SPL
But by doing so the noise would also be 50dB SPL louder and no longer below 0dBSPL

Same measurement same noise same 100Hz (simulated mains harmonic)
The only thing i have changed is the absolute amplitude of the 1k test signal. They are defined as 120dBSPL
But by changing 1k reference amplitude i can shift the noise floor and the 100hz mains harmonic around however i want.
1658279602513.png



( i applied smoothing, i know this introduces errors but his is a visual aid and smoothing helps to see what going on if lines overlap)
 

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DualTriode

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You have a clue if you can read:

index.php


The reference is clearly stated: 120 dBSPL. Any spikes below then is relative to that. Once you hit negative dB relative to that, i.e. below 0 dBSPL or thereabouts, you are below threshold of hearing.

dB SPL is not a voltage reference. The scale on the graphic is Voltage referenced. dB SPL is a pascal referenced number. Perhaps put it on the left hand side of the Graphic and not mix Pascals and Volts.

Your analyzer has Analog Outputs and Analog inputs. The measurements in this thread are scaled to volts, and a software dBrA of your choosing. Bottom line the outputs and inputs are scaled in analog Volts. Your digital comments do not apply to the measurements in this thread; there were no digital music files.

My comments stand.
 
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amirm

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dB SPL is not a voltage reference. The scale on the graphic is Voltage referenced. dB SPL is a pascal referenced number. Perhaps put it on the left hand side of the Graphic and not mix Pascals and Volts.
You still don't know what a dB is.
 

JohnYang1997

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It just means, even if the final acoustic output of whatever is hooked up to the device is as loud as 120dBSPL with the given voltage the noise is still inaudible.
If the acoustic output ended up being lower than 120dBSPL the noise would only be even more inaudible.
 

DualTriode

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You still don't know what a dB is.
I understand the intent, speaking of audibility.

You still can not mix Pascals and Volts even if there are dB's in front of them.

If this were an Adult Wechsler question you would only get partial credit.
 

kencreten

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Maybe the price for the GR power cable is indeed way too low to show those superlative benefits advocated by so many audiophile magazines. Amir, would you consider to test this one? It is sensibly priced at $ 34,999 for a generous 1.25 m length. Made here in the Commonwealth of MA.View attachment 218209
I have to admit myself that this is a fine looking cable. I would buy it, but I cannot believe how they left off silver accents. A huge oversight.
 

welsh

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Is that the only reason for purchase?
If so, yes that was a waste of money. That ought to be clear.

Seems like a nice product for many reasons but I would much rather have more power. In any case if you only purchased to gain 15-20SINAD over what would have already been transparent then woops. Might as well have bought this power chord :)
I frequently use power chords when playing the guitar, but prefer power cords when connecting things to the mains.
 

MerlinGS

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It is not. We do it day in and day out in science and in real life. It is a fallacy and high-school debating line to say what you did. Those of you who make this false argument are in dire need of reading this short article from professor Steven Hales: https://www.cambridge.org/core/serv...f/thinking-tools-you-can-prove-a-negative.pdf

"But there is one big, fat problem with all this. Among professional logicians, guess how many think that you can't prove « a negative? That's right: zero. Yes, Virginia, you can prove a negative, and it's easy, too."
@amirm I enjoy reading many of the sources you provide, but this one I don't care for too much. I will very briefly state my concerns (don't want to derail the thread). The author plays fast and loose with the meaning of proofs and totally misrepresents proofs in science. As you well know, the scientific method does not prove a theory, all it does is test the null hypothesis. Philosophy of science is filled with examples of scientific advancement being affected by perceptions, dominant perceptions, and paradigm shifts. This PC study is another apt example. You can study as many cables as you want, but in the end, all we can accomplish is show that there is no evidence to suggest the contrary. When "believers" dream up stupifying theories to support their views, then we can develop hypotheses to test their theories, and determine if their "theory" is able to explain any of the data available to us. However, as @JanesJr1 already stated, Popper noted that all it would take is one contrary incident to disprove years of accumulated data and study. So no, science does not absolutely prove the existence of things, but it is able to provide us with the means to study and understand our experienced reality by providing us with many tools to circumvent our human filters/limitations (please note that there is value to having filters, it provides us with the means to interact with each other as a community).

Not being able to prove the negative is problematic since the subject proposing the stance can continue down a path of "infinite" absurdum, the very nature of the claim does not allow for reasonable proof (e.g. the listener must be able to view the equipment being tested, otherwise they are under too much stress to evaluate the equipment); that is why individuals making extraordinary claims are generally expected to provide strong evidence to support their claim (sadly in the history of science, sometimes this has led to the perpetuation of poor theories until sufficient non-explainable data was gathered to destabilize the old predominant theory).

2 examples of extraordinary claims:

1. One of Descartes' arguments suggested that we may be living in a fantasy world created by super powerful being (yes, hundreds of yrs before the Wachowski brothers (they were brothers at that time) created The Matrix, Descartes had already conjectured about the possibility of living in a fictional realm) controls all of our experience, then nothing is real (in a "Platonic" sense). All experience is subject to the creation of the superbeing (or as some in the field you used to work in have contemplated, you/I/we could be nothing more than the result of an algorithm created by a complex computer program/AI. None of these can be disproven, we can merely attempt to develop theories and test hypotheses to examine how the above noted claims of fictional reality may be "proven" if "real".

2. We are all under the mind control of powerful aliens, and the thoughts we think we have are the result of controls they have implemented in our thinking process to make us believe and experience in a particularly specific way to serve their needs. Oh... and the reason people can hear the difference between cables is that they are momentarily able to break from the control of such aliens, but the aliens have forced particular ways of thinking into our reasoning process to be able to "disprove" those actual moments of lucidity.

As you can see, the power of the negative is that it can always be stretched beyond the realm of our ability to prove the contrary. The debate about God's existence has been going on for over millennia, and brilliant people on both sides have attempted to prove their claims. I don't need to tell you how that is going.
 
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amirm

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that is why individuals making extraordinary claims are generally expected to provide strong evidence to support their claim (sadly in the history of science, sometimes this has led to the perpetuation of poor theories until sufficient non-explainable data was gathered to destabilize the old predominant theory).
I do the opposite day in and day out here. The other side will point to "what they hear" and say that is the ultimate proof. We can't then just sit here and say we can't prove a negative so we are stuck. We produce our own evidence of lack of effectiveness. Back it with design and engineering and arrive at a compelling conclusion. I don't care if out of thousands of AC cords, one does something in some rare situation. I don't live my life that way so don't see why it should be the case for audio. There is some probability that I will have a car accident if I drive it. Should that stop me from using the car? We make judgements with low probability of error all the time. So the same needs to be true for audio.

This has also become a talking point that we need to get rid of. We need to be fact based, not argument based. We are the camp that supposed to know better. So why would we want to sit here for the other side to prove something?
 

MerlinGS

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I do the opposite day in and day out here. The other side will point to "what they hear" and say that is the ultimate proof. We can't then just sit here and say we can't prove a negative so we are stuck.
@amirm, you are totally right, that is the problem; however, the response should not give them an easy way out. As you have personally experienced, trying to prove a negative is a path filled with counterarguments based on poor logic, bordering on irrationality. There is a reason why people making extraordinary claims in audio (and any field of study or claim) should be required to prove their assertions. That is why I think many of your cable reviews are of value. The many people who may question your process and conclusion fail to understand that they are not addressing your argument. The argument is not whether a particular test disproves all events, but rather whether it disproves particular theories and claims. Many of these "high-end" audio manufacturers are forced to create theories and magnificent claims to market their products. Sadly, visiting sites such as Audiogon (the irony of the name) demonstrates many consumers easily buy into said theories/claims, because most consumers either lack a very basic understanding of science or resort to magical thinking to advance the acceptance of their experience (studies show how magical thinking helps us handle stress and accept that which we don't understand). Actually, you know of medical people who were good at their field and yet, don't seem to understand the basic application of scientific methodology and medicine to other fields, such as audio.

As to the other side's ultimate proof, they need to better understand that we share their view, hearing should be the proof; i.e. not seeing. Consequently, it is important that any extraordinary claim should be at the very least demonstrable under simple double-blind tests, with proper measures ensuring the DUT is working under proper parameters when being tested, and products being compared are level matched to within .1 dB. Clearly, some things in audio electronics and in some instances cables are audible; e.g. tube amplifiers with high output impedance, electronics with audible distortions or poor frequency response, cables with high capacitance and MM cartridges, etc., but the question is whether the theories/claims being proposed by many of these "high-end" priests, members of the flock and manufacturers (collectively the "cognoscenti") have any basis in fact. Your tests, despite the claims of limitations by some, clearly attempt to address the aforementioned theories/claims, and the criticisms of your work should first determine if the tests advanced fail or succeed in their purpose. In virtually all cases, the tests you provide do specifically address the theories/claims made by the "cognoscenti". Can concerns be raised about the tests from other perspectives? In some cases, yes, but those issues should be recognized as secondary since the primary purpose of the tests was to address particular claims and theories of the self-appointed "cognoscenti". The old expression of the bath water and the baby is clearly applicable here.

I would suggest that discussion could be better facilitated if critics of the tests should first acknowledge whether the tests in question met their purpose (testing the theories/claims advanced by the "cognoscenti"), if no then the critics should explain where/how the test fails to address the theories/claims; i.e. directly connect their concerns with the theories/claims advanced by the "cognoscenti", not some other theoretical issue. Then the discussion will not diverge into areas totally unrelated to the purpose of the test. If the critic feels the test did meet its purpose but failed in some other fashion, then the critic should clearly acknowledge how the test met that purpose, and then suggest how the test may be improved to address other areas of concern.

Once again, I better stop before I further derail @amirm's thread.
 

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Perhaps neither here nor there with the particular 'largeness' of this thing's ground pin, but I've had a lot of success with Deoxit lately on all of my power outlets, inside and out. Shoot a small amount into each of the three (or two if ungrounded - older buildings) socket holes and it's so much easier to plug and unplug every power cord. Also I can see it extending the service life of my outlets given I no longer have to use much mechanical force, which of course gradually loosens both mechanical and electrical connections. I'm sure Amir's sockets are fine, but wonder if a little Deoxit would make plugging something like this in??

Also thanks for the Radical Face plug. I've never heard of them and am listening on Tidal now. Will be adding to my list of test tracks, at the least. Further O/T another artist to use for listening (and tests) is Christone "Kingfish" Ingram, with his albums "Kingfish" and "662" - nice guitar blues with a good mix of SRV and Buddy Guy. The dude's a prodigy at about 23 years old.

Final note, it sure looks like a lot of 'audiophile' cable companies have incorporated the word "research" into their brand names. How much research really gets done by these firms, other than marketing and branding research?
 
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DualTriode

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Has anyone actually measured the U-slot ground on this cord?

Is it really out of spec?
 
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amirm

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Final note, it sure looks like a lot of 'audiophile' cable companies have incorporated the word "research" into their brand names. How much research really gets done by these firms, other than marketing and branding research?
Nothing that I can see. Building a cable doesn't even rise to the level of "design work" let alone research.
 

JSmith

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This cable is a hobbled together piece of garbage and offers nothing but inconvenience, noted by the idiotic plug sheath and overly long ground pin. Expensive power cables never have been and never will be a productive way to address a ground loop, especially in this case where it really is just a cable only. If this cable isn't properly certified or shown to comply with standards, then if something happened in the home ones insurance may be invalidated.


JSmith
 
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