I guess I'm just being Mister Whiny Poopy Pants about it. Getting all four wires into the grub screw cups simultaneously seems harder than necessary, but it wasn't the end of civilization as we know it.
All good fortune,
Chris
There are two sorta related papers by the same author, the previous one having to do with headphone cables: AES E-Library >> Perceptually Affecting Electrical Properties of Headphone Cable — Factor Hunting Approach
The more recent paper talks about audible cable effects in the case of high-Z loads.
A 'slight' problem is that this paper does NOT show any audibility or inaudibility of audio cable. The author proposes a physical mechanism for a change in the electrical characteristics of an audio cable. The change in electrical characteristics is then simulated using DSP. There was no listening to audio cables as such.
It is an interesting technique in terms of investigating the threshold of audibility of a change X where X can be manipulated. Not sure that it has anything to do with ABX either as the actual experimental listening technique is not discussed
The high impedance is defined as greater than 1k but it is a little unclear whether than is load or source impedance
Upon taking another look at it, is appears listening tests were performed for headphone cable (real or simulated?) in the previous paper : "From this result, although roughly, it can be seen
that if the variation of the time constant is from -1 to
10 ps in consideration of the boundary value, threequarters
of persons cannot recognize the change in
the sound quality due to the variation of the time
constant. Note that the range is asymmetric with
respect to the sign. The range that almost all people
cannot recognize may be considered to be one tenth
of that. This is the result of listening with
headphones. When using loudspeakers, the result
can be a little different, and depending on other
playback environments, it is one index that gives a
limit to the discrimination of changes in sound
quality."
Having previously determined cable time constant variations at the threshold of audibility in the headphone cable audibility paper, the time constant threshold of audibility results were discussed in relation to time constant variation due to capacitance variation as determined in the the current paper.
Hopefully, that was clear. Have to agree that the translation from Japanese requires some careful reading.
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Did you take care of Demian, Markw4, with regards to the paper? I was going to offer, but I forgot to call him for his e-mail address. Personally I am tempted to rejoin the AES, if papers of this type remain available.
I'm an AES member. Have full access.
I'm having an issue with the cable changing delay to the tune of 10 pS. First finding audibility in that does stretch credibility. Second, an issue like that would show up quickly in precision time measurement. I have the instruments to measure such a change and have never seen it, not that I was looking but it would be hard to miss when your cable got longer when the level went up.
Also everything from the semconductor at the source to the same at the receiving end will have a voltage coefficient. Usually very small but for this it would be enough to scramble the results. Most semis are quite high, viz varactor diodes.
I'm having an issue with the cable changing delay to the tune of 10 pS. First finding audibility in that does stretch credibility. Second, an issue like that would show up quickly in precision time measurement. I have the instruments to measure such a change and have never seen it, not that I was looking but it would be hard to miss when your cable got longer when the level went up.
Also everything from the semconductor at the source to the same at the receiving end will have a voltage coefficient. Usually very small but for this it would be enough to scramble the results. Most semis are quite high, viz varactor diodes.
LOLOL, now that you mention it, it is true: cutting the individual conductors short enough so the cable clamp chuck gets a good grip on the jacket does mean a bit of fuss grooming the conductors to hit their respective holes without stray strands mucking about...especially with the 8-conductor ones I've been doing. I do like the improved STX series with the angled screws, it seems to make it easier and certainly the pull-out has improved.
**CAUTION** RHC (Retirement Home Content) ahead***
The worst plug to install I ever had to deal with was Plumbicon camera cable plugs for TV stations in the 1970s. I worked in a Audio/Video dealer right out of high school, and they installed and repaired TV station gear. Since I was the young guy with the good eyes I was tasked with soldering the dang BIW plugs...new blue style 2
It would take me the better part of a shift to do one properly with served full shielding on the coax pins and proper heat shrink on each. After having to do those, I guess I felt the smaller once were a relief...
Cheers!
Howie
Understood. I have to wonder if the paper's author is measuring or trying to measure the right thing. Cables do have audible effects in many cases, but likely more than one mechanism is involved. One or more mechanism(s) are not controversial, for example we know transfer impedance can account for coupling of noise into signals which can then have various audible effects depending on the details, including noise interaction with circuitry. But, it seems there is something more, a filtering effect is mostly what it sounds like. A cable time constant voltage coefficient may or may not be the right explanation, but I can see why someone might go hunting for that possibility given how some cables sound.
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Although in my retirement years, haven't lost my taste for RCH's (Another Matter Altogether).
Always the best,
Chris
“reported successful ABX trials”
“some memory or time based effect”
Are these two elements present in the AES Convention Paper 10338?
George
“some memory or time based effect”
Are these two elements present in the AES Convention Paper 10338?
George
Sounds like prophecy, open to interpretation, almost like a "religion" eh Mark? 😉
My fastest scope has 9 ps rise time and that takes 50 GHz bandwidth.
So I could see it in principle, if I pay the $300 for the 2.4mm coax connector
and keep the input cable short, as in few cm.
The TDR must make do with 20 ps rise time but it shows minor impedance
variations in precision connectors without mercy.
Just hold your hand next to a microstrip and everything changes.
Speaker/head phone cable aberrations would not fit on the screen then.
That thing is completely disconnected from reality.
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Nothing to be concerned about. Brief summary:
Physical deformation of cable by electrostatic forces may lead to capacitance modulation. Under extremely extreme circumstances this could possibly result in barely audible artifacts.
To quote from the paper itself once again:
"In the case of audio signal transmission over an
audio cable, it is shown that the change in the
capacitance of the cable due to the voltage of the
transmitted signal causes an audible change in sound
quality, and the voltage dependence of the
capacitance is measured for some unbalanced and
balanced cables. In addition, it has been
quantitatively shown that the output impedance on
the drive side may be reduced to a level at which a
change in sound quality due to a change in cable
capacity cannot be detected. However, it was also
detected that the cable capacity could change slowly
with signal voltage, and analysis of the effect of this
phenomenon on audible sound quality remained.
There are many factors that affect sound quality in
the process of recording and reproducing sound.
Focusing on only one factor does not result in a
balanced system as a whole. It is desired that a
quantitative evaluation index be given to other
audible sound quality change factors."
The second fact, that the capacitance could 'change slowly' is a memory or time-based effect, at least to my reading of the paper. The effect is shown in some of the graphs for some of the cables.
"In the case of audio signal transmission over an
audio cable, it is shown that the change in the
capacitance of the cable due to the voltage of the
transmitted signal causes an audible change in sound
quality, and the voltage dependence of the
capacitance is measured for some unbalanced and
balanced cables. In addition, it has been
quantitatively shown that the output impedance on
the drive side may be reduced to a level at which a
change in sound quality due to a change in cable
capacity cannot be detected. However, it was also
detected that the cable capacity could change slowly
with signal voltage, and analysis of the effect of this
phenomenon on audible sound quality remained.
There are many factors that affect sound quality in
the process of recording and reproducing sound.
Focusing on only one factor does not result in a
balanced system as a whole. It is desired that a
quantitative evaluation index be given to other
audible sound quality change factors."
The second fact, that the capacitance could 'change slowly' is a memory or time-based effect, at least to my reading of the paper. The effect is shown in some of the graphs for some of the cables.
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Forces generated, uncertainties and all relevant data have been disseminated decades ago by primary Cal Labs (search for ‘electric realization of force’)
Small Mass and Small Force Metrology at NIST | NIST
(PDF) SI realization of small forces using an electrostatic force balance
https://www.imeko.org/publications/tc3-2002/IMEKO-TC3-2002-029.pdf
George
The thing is that when a (subjective) difference in sound is perceived, it triggers the search for a cause.
When something is found, this will most likely be bombarded as the cause for the sound difference although the correlation seems mostly very far fetched.
Over the years I've seen so many completely different and mostly conflicting explanations why cable A sounds better as cable B, that I've lost track and don't even bother reading the papers.
Hans
When something is found, this will most likely be bombarded as the cause for the sound difference although the correlation seems mostly very far fetched.
Over the years I've seen so many completely different and mostly conflicting explanations why cable A sounds better as cable B, that I've lost track and don't even bother reading the papers.
Hans
Its a complex subject. Multiple effects could be involved at once and the exact balance or weighting of effects may vary depending on very local conditions. A typical FFT might not show some effects especially if someone just throws together a test based on incorrect assumptions about causation.
So its complicated to figure out, that doesn't mean some people should automatically jump to the conclusion that subjective perceptions are imaginary. Maybe so, maybe not.
Blind testing is fine, although I would much prefer A/B double blind or a double blind sort test like I once used. There are perfectly good double blind protocols other than just ABX. Its seems like an historical quirk that somebody started selling ABX boxes and promoting that particular protocol and seemingly as a result the least sensitive protocol (according to Jakob2) has become the most popular one among skeptics.
The question I have is how can I do double blind testing at home by myself or with one other person, and that will be accepted as reliable evidence. I wouldn't expect skeptics to accept such a process, its too easy for them to imagine something done wrong to invalidate the results. It would take a neutral proctor and maybe third person to run the test in order to meet double blinding requirements. Even if neutral people were hired to come out and do the work, skeptics still would probably imagine some reasons why they shouldn't have to believe the results. The foregoing is where the biggest problem is IMHO with regard to ending the arguments about what people can or can't hear.