Audio Test of Power Conditioner by Audioquest

[Ingenieur]

The basic premise of the test:
A is wall power
B is a highly regarded PC
C is the AQ PC

They play CD music and digitize the sample powered from each source.

First they use wall power A and capture a sample and null it with itself. It cancels to 0, no surprise here.
They do NOT measure the noise component.

Second: they capture a sample powered from source B PC
They null it with A + (-B)
The resultant is the noise in A that B removed and that would mask the music.

Same for C, nulled with A, less noise.

But we do not know the actual relative levels. It could be A, B, C = -120, - 121, -122. We do not know if the noise level is > the signal.

I had to read it 3 times. It is nonsense.
Your tests are being discussed on another forum where the OP said this is proof it does nothing, yet people still hear things.
One heard a reduction in 60 Hz hum and attributed it to the AQ box. Really!?

 

[Ingenieur]

I had to look at it again, it makes no sense.
I'm not the sharpest knife in the drawer but I DO breath thru my nose contrary to popular opinion.

I had to draw a picture. I think what they are showing is residual below the null value or noise removed.
So the generic removed ~ -70 dB or 0.03% of the noise and the AQ -60 dB or 0.1% of it? When it nulled to-140 dB to begin with case A?
I bet that is why they did it that way.
All 3 cases are below 140 and could not be measured.
I hope I'm mistaken.

 

[amirm]

Thanks for trying you all. Any write-up that is so obtuse that can't be understood by multiple people, has no value. These people need to learn to write and document experiments.

 

[Ingenieur]

Thanks for trying you all. Any write-up that is so obtuse that can't be understood by multiple people, has no value. These people need to learn to write and document experiments.

I think they intentionally made it confusing.
I believe we have the gist and it removed <1% of noise that was already well below the signal and audibility.
Exactly like your results.

Any difference is literally lost in the noise and made moot by environmental factors and variation in PQ.

I hate when our profession is used to fool people.
Engineering has a Code of Ethics, which is obviously lost on some.

 

[RayDunzl]

Engineering has a Code of Ethics

I did not know that:

Code of Ethics | National Society of Professional Engineers

NSPE Code of Ethics for Engineers Download: NSPE Code of Ethics Download: The NSPE Ethics Reference Guide for a list of all cases through 2019. Preamble Engineering is an important and learned profession. As members of this profession, engineers are expected to exhibit the highest standards of...

www.nspe.org

 

[Ingenieur]

I did not know that:

Code of Ethics | National Society of Professional Engineers

NSPE Code of Ethics for Engineers Download: NSPE Code of Ethics Download: The NSPE Ethics Reference Guide for a list of all cases through 2019. Preamble Engineering is an important and learned profession. As members of this profession, engineers are expected to exhibit the highest standards of...

www.nspe.org

It is also written into most states licensure laws. No one is perfect, we slip, but you must strive. Don't prostitute it.

A prof gave me thisdecades ago when I was in school. It should be mandatory.

http://artjohnson.umd.edu/courses/bioe332/bioe332-hoover.pdf

 

[BlackTalon]

Possibly why some designers say they have a degree in electrical engineering. They may not actually be licensed professional engineers. Following the state codes of ethics normally is for licensed professionals (a requirement you agree to upon licensing and renewal).

 

[Ingenieur]

What is staggering is the lack of understanding of non-technical 'audiophiles' about this subject. They think AV power supplies are some sort of magic.
And the PS of a $30k DAC can be improved with a $8k power cord.

Tell them a 2 meter $8k 14 AWG cord is bettered by a 1 meter 12 AWG $15 Amazon cord and their heads will explode. But neither will sound different from the one that came with the DAC. Mind boggling.

Engineer's learn about power supplies based on load conditions, not application.
Mil spec, medical, aviation, process control, lab use, digital, communication, all the same. The engineer, if different, designing the load will spec what they want for their device to meet spec.

These power strip, power cord/cable guys are religious zealots.
Akin to despite what science proves, the Earth is the center of the universe, is flat.

Cable lifters, little dots on headshells, etc.
It's funny, and meaningless, who cares if people with $ burn it. Lol

The consolation, once in a rare while, a person will come forward and acknowledge they fell for the hype and wasted $ with no benefit.
Far and few between though, takes guts to admit you fell for a scam, people never want to admit being duped or wrong.

 

[ahofer]

The consolation, once in a rare while, a person will come forward and acknowledge they fell for the hype and wasted $ with no benefit.

Oh, I freely admit it, as do many others here.

But it usually takes some time. When first confronted with the hollowness of high-end promises, it is indeed the rare individual who admits they were mistaken, as opposed to invents some rationalization about unmeasurable qualities or inadequacies of blind-testing.

My first blow to the head was in 1987 (Stereo Review blind amplifier comparison). But I bought some expensive speaker wire as late as 1993. Then I stopped worrying about amps (other than power) and cables. And I bought SACD and fancy DACS after that.

 

[KSTR]

In the paper, there is some kind of null test conducted by Bernie Grundman at his mastering house. I have read it a few times but still can't figure out what the test is. Usually in a null test, the lower the null, the better it is. Yet the claim is the reverse here. The say their power conditioner produces the loudest difference signal! At least that is my read of it.

As far as I understand it, their "brilliant" idea was this:
Measure normal state as baseline (and check if it nulls well in repeated measurments).
Simply assume that a cleaning device will actually reduce the noise so that the non-zero residual represents how the cleaner did improve things.

They missed that the residual would be non-zero as well when the cleaner just produced a different noise profile, including a higher/worse one.
Basically their method just shows that there is a difference but one cannot infer anything else from that.

The only way to judge if the audio is less corrupted with cleaner device vs without is by recording the signal and comparing it with the original source signal/file. This requires some effort but with the help of tools like DeltaWave it can be done properly, today.

 

[Ingenieur]

Possibly why some designers say they have a degree in electrical engineering. They may not actually be licensed professional engineers. Following the state codes of ethics normally is for licensed professionals (a requirement you agree to upon licensing and renewal).

I consider engineering as a profession and licensure as 2 separate things.
BOTH should adhere to basic ethically standards. It should not require a piece of paper.

 

[Ingenieur]

Oh, I freely admit it, as do many others here.

But it usually takes some time. When first confronted with the hollowness of high-end promises, it is indeed the rare individual who admits they were mistaken, as opposed to invents some rationalization about unmeasurable qualities or inadequacies of blind-testing.

My first blow to the head was in 1987 (Stereo Review blind amplifier comparison). But I bought some expensive speaker wire as late as 1993. Then I stopped worrying about amps (other than power) and cables. And I bought SACD and fancy DACS after that.

I run 50/50. I have a lot of experience being wrong. I do not blame those who are technically untrained and rely on others for opinion. I do question when it is laid out for them that 2 identical power signals make no difference. And when further shown those supplies feeding a source and its output signal is identical there can be no audible difference cling to their position "I hear a difference". To each their own.

In a system with:
Source material
Signal source power
Signal source output
Amplification plus it's power source
Interconnecting cables
Speakers
Room
Ears

By changing one power cable in a device that may be 5% of the equation, and power supply is <0.1% of that 5%, they hear a remarkable improvement. It defies logic.

 

[Ingenieur]

It comes down to trust, or faith, but not as perceived by some, not your ears, but in the guy telling you your ears are deceiving you. If someone knows more about a subject than you and illustrates why what you think can happen, can't, and that is the overwhelming consensus of those subject matter experts, believe them, not your personal feelings.

Case in point:
A doctor shows me an x-ray, looks like a blur to me. He points out a blob and says this is an issue that must be dealt with.
I won't say 'you are wrong', I felt that spot and there is nothing there'.
I may seek a second opinion, but not 50 opinions. But I will believe him until others prove him wrong.
I will not allow my insurance company to tell me 'no, ignore him, he's wrong,!you don't need surgery, trust your feelings'.

But hey, it's a strange world.

 

[BlackTalon]

I consider engineering as a profession and licensure as 2 separate things.
BOTH should adhere to basic ethically standards. It should not require a piece of paper.

that's fine, but the codes of ethics are from the engineering associations and the State licensing authorities. People wirh engineering degrees but who are not licensed (or at least a member of the relevant association) are not bound by them. I'm not trying to argue but merely pointing out the reality.

 

[ahofer]

It comes down to trust, or faith, but not as perceived by some, not your ears, but in the guy telling you your ears are deceiving you. If someone knows more about a subject than you and illustrates why what you think can happen, can't, and that is the overwhelming consensus of those subject matter experts, believe them, not your personal feelings.

Case in point:
A doctor shows me an x-ray, looks like a blur to me. He points out a blob and says this is an issue that must be dealt with.
I won't say 'you are wrong', I felt that spot and there is nothing there'.
I may seek a second opinion, but not 50 opinions. But I will believe him until others prove him wrong.
I will not allow my insurance company to tell me 'no, ignore him, he's wrong,!you don't need surgery, trust your feelings'.

But hey, it's a strange world.

Well…here we do want people to trust their ears, and we are generally fine with peoples preferences. The sticking point is whether the signal they are getting is, in fact, coming through their ears…..hence the obsession with blind testing.

It’s a funny tension between “trust your ears” and ”trust expertise”, and many saying the former seem to mean the latter - only not the type of expertise that is tested rigorously and open to scrutiny.

 

[DonR]

In Canada, as part of the Ritual of the Calling of an Engineer, you are required to recite The Obligation which is an expression of the intention of professional conduct. Not an oath but close. If the engineer wears the Iron Ring, he has recited that obligation. That doesn't mean they are honest though... haha.

 

[Ingenieur]

that's fine, but the codes of ethics are from the engineering associations and the State licensing authorities. People wirh engineering degrees but who are not licensed (or at least a member of the relevant association) are not bound by them. I'm not trying to argue but merely pointing out the reality.

Morals and ethics apply to all.
People CHOOSE to abide by them.
There are often sanctions for not doing so, therefore having a license is not the determining factor.
Character (or lack thereof) is.
THAT is the reality.

Our DL training and obligations inform us not to drive drunk. But licensed and unlicensed drivers do, and you have the opposite. What determines that?
The license? Or the person?

 

[Ingenieur]

Well…here we do want people to trust their ears, and we are generally fine with peoples preferences. The sticking point is whether the signal they are getting is, in fact, coming through their ears…..hence the obsession with blind testing.

It’s a funny tension between “trust your ears” and ”trust expertise”, and many saying the former seem to mean the latter - only not the type of expertise that is tested rigorously and open to scrutiny.

People will do as they please, usually to please them, not benefit them.

For example a mechanical engineer tells you the rope you are lifting a safe with is going to snap and you reply 'I feel it will not', that is not good information analysis.

People believe they are always smarter than the other guy, politics, money, philosophy, etc. They can be taught nothing.

If you think you are the smartest guy in the room, you are not.
I know I never am: because people constantly tell me they are, therefore I can't be.
I prefer to think I am likely not the dumbest person in the room, better odds, but not by much.

 

[MaxBuck]

that's fine, but the codes of ethics are from the engineering associations and the State licensing authorities. People wirh engineering degrees but who are not licensed (or at least a member of the relevant association) are not bound by them. I'm not trying to argue but merely pointing out the reality.

Correct so far as it goes. But from a professional liability perspective, failure to abide by these ethical codes can be problematic and perhaps costly, regardless of the registration status of the practitioner.

 

[Chrispy]

Engineer and fraudioquest just doesn't compute.