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What do we hear when we change the direction of a wire?

Douglas Self wrote a devastating article about audio anomalies back in 1988. With all the necessary knowledge and measuring tools, he did not detect any supposedly audible changes in the electrical signal. Self and his colleagues were sure that they had proved the absence of anomalies in audio, but over the past 30 years, audio anomalies have not disappeared anywhere, at the same time the authority of science in the field of audio has increasingly become questioned. It's hard to believe, but science still cannot clearly answer the question of what electricity is and what sound is! (see article by A.J.Essien).

For your information: to make sure that no potentially audible changes in the electrical signal occur when we apply any "audio magic" to our gear, no super equipment is needed. The smallest step-change in amplitude that can be detected by ear is about 0.3dB for a pure tone. In more realistic situations it is 0.5 to 1.0dB'". This is about a 10% change. (Harris J.D.). At medium volume, the voltage amplitude at the output of the amplifier is approximately 10 volts, which means that the smallest audible difference in sound will be noticeable when the output voltage changes to 1 volt. Such an error is impossible not to notice even using a conventional voltmeter, but Self and his colleagues performed much more accurate measurements, including ones made directly on the music signal using Baxandall subtraction technique - they found no error even at this highest level.

As a result, we are faced with an apparently unsolvable problem: those of us who do not hear the sound of wires, relying on the authority of scientists, claim that audio anomalies are BS. However, people who confidently perceive this component of sound are forced to make another, the only possible conclusion in this situation: the electrical and acoustic signals contain some additional signal(s) that are still unknown to science, and which we perceive with a certain sixth sense.

If there are no electrical changes in the signal, then there are no acoustic changes, respectively, hearing does not participate in the perception of anomalies. What other options can there be?

Regards.
anton_stepichev
dletch2
455 posts
 
The time-frequency uncertainty principle states that the product of the temporal and frequency extents of a signal cannot be smaller than 1/(4?). We study human ability to simultaneously judge the frequency and the timing of a sound. Our subjects often exceeded the uncertainty limit, sometimes by more than tenfold, mostly through remarkable timing acuity. Our results establish a lower bound for the nonlinearity and complexity of the algorithms employed by our brains in parsing transient sounds, rule out simple “linear filter” models of early auditory processing, and highlight timing acuity as a central feature in auditory object processing. (Emphasis added.)»


Mahgister, I am giving you the benefit of the doubt that you understand that this does not mean that humans have "magical" properties. It only means that our auditory system is not purely tone based, which again, has not been overly debated in over a century.  Pitch is still tone, as it is a definition and it is continuous, it does not involve attack and decay.


Instruments can time two waves of the same frequency to way better than 1/4 wavelength. Say you have two A/D recording the same sound, at 44.1KHz, 20KHz bandwidth limited. They are asynchronous, i.e. there is no synchronization of there A/D. In software I can resample and align those two recordings to an accuracy of sub-microseconds determinant on the SNR/THD.  So much for 1/4 wavelength.


dletch2
455 posts
 
I would believe whatever differences there are would show up most in cases where there is an impedance mismatch which is much more likely with zero feedback amps, but that should not really matter if one has addressed impedance matching between amps and speakers properly, which is the right way to do it for best results, so in that case impedance matching issues due to a zero feedback amp is a moot point.  



This would be virtually impossible, since impedance is variable with frequency across the audio band, impedance of speakers are not complex, and not controlled anywhere within the speaker itself. Given the mechanical nature, it may not even be a practical goal.
sj00884's avatar
sj00884
80 posts
 
Who “listens” to electricity or electrical characteristics/properties? Sound is created, or in this instance recreated, by a vibrating transducer(s); how is that movement measured objectively/scientifically? 
I am definitely in the camp where “everything matters”. I have no idea how some of the tweaks I’ve incorporated work, or even if they do. If I “notice” a change over extended listening +/-, perceived or otherwise, the answer is quite clear. 
dletch2
455 posts
 
@anton_stepichev, you really need to get your facts straight!

I never wrote this quote that you are assigning to me. In fact, when I do a search on those exact words on this forum, the only person who has posted them is YOU. As you used the words, "STATEMENT", that implies you were directly quoting me. You were not directly quoting, and if you think you were paraphrasing me, you are not.

anton_stepichev OP77 posts04-24-2021 1:50am
dletch2, you haven't finished explaining your previous statement yet:

"The interference of a power cable can get into the signal circuit and become audible not as periodic interference of 60Hz harmonics, but as non-periodic one so that initial frequency of 60 hz is perceived as something related to a musical signal (for example, frequency response), and not as interference or noise."




THIS IS THE EXACT WORDS I USED!!!   There is nothing to explain in this. This is electronics and signals 101. Anything I have written is only muddy to you because you do not understand it. I can't help you on that. We are obviously not working at the same levels.

This is not an advocacy for expensive power cables, but there are many ways the harmonics in the AC to get into the signal. Whether they do or not is a different question. The most obvious one is via the power supply, especially in a low feedback amplifier. Primary power supply harmonic is 120Hz, but with all the linear supplies, there are harmonics at many multiples of that frequency, certainly up to several KHz. Those big transformers audiophiles love get rid much of the really high frequencies.

Those high current peaks from the power amplifiers generate harmonic noise on the AC line that can get into other power supplies.

Those high current peaks can generate higher frequency EMI that can get into signal lines (at least a justification for shielding).

I don't see a lot of justification for the cost or claims about most high end power cords. Most of these power cord / cable designers have little knowledge of electronics which is evident in their claims. It works because their customers do not either. Vicious circle.

That 60Hz buzzing is not always just 60Hz. It is only something that happens 60 times a second. There can be rich harmonic content in that 60Hz buzz.   Now that take 60Hz and harmonics and modulate a music signal with it. Now you have stuff all over the place.

anton_stepichev OP
150 posts
 
Dletch2, no one is interested in rereading an infinite number of quotes and analyzing them. I've definitely covered up a question that you didn't answer directly by engaging in abstract demagoguery. I apologize that it looked like a direct quote.

Dletch2
THIS IS THE EXACT WORDS I USED!!!
In your direct quote, there is nothing like a logical analysis of the possible occurrence of audible distortions in the signal circuit when changing the power cable. I have to repeat, in order for your words to be at least somewhat similar to the evidence, you must provide:

1 - numerical or relative estimation of the level of possible interference
2 - numerical or relative estimation of the level at which the interference penetrate the signal circuit
3 - In what exact place it penetrates the signal circuit

On the same points you have to explane your EXACT statement, that you made not long ago:

Dletch2Does not work that way. If the error is simply frequency response, the relationship between the perfect and imperfect signal never changes...

So, first of all you should explain, how the difference in frequency response can occur when a short piece of wire is reversed?

Numerical or relative please.



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