1) it is possible for a cable to have a physical directionality.
2) However as I pointed out, not in the audio range,
3) A cable assembly is different from a cable, assemblies with networks can be directional.
2) However as I pointed out, not in the audio range,
3) A cable assembly is different from a cable, assemblies with networks can be directional.
Again: why waste time here on fully unrelated aspects?
It beats me.
It beats me.
Is someone supposing that cables are directional because they are not physically uniform along their length?
IOW that a common-mode effect due to different impedance distribution along the cable is the culprit?
I can't see how consistent directionality could be real in a uniform transmission line.
IOW that a common-mode effect due to different impedance distribution along the cable is the culprit?
I can't see how consistent directionality could be real in a uniform transmission line.
If you watch the video in the first the post, you will have an answer to your question.
That video didn't shed much light. He took a very long time to say that directionality only matters in cables used to conduct power to devices.
When I was a kid we had so-called DIN connectors here. The cables with such connectors were called "diode cables" (why?) so I really thought the cables were rectifying something 🙂
This discussion has been mostly about speaker cables, since that is where the big snake oil problem exists. And I think Gene has been very clear about it.
There are some directionality issues with various equipment interconnect cables. And those need to be treated on an individual basis, because there are significant grounding differences in each case.
And then for the third type of cables, AC power cords, we are back to a huge snake oil fiasco again.
Actually, power cords have both snake oil involvement, as well as actual EMC design problems.
Two widgits powered three prong with an RCA interconnect between, most out there do not understand the signal return path is NOT the shield of the interconnect, but a combination of line cord ground and shield. Two shields if stereo.
And all the LF signal returns via the power cord ground, the break frequency for full containment within the interconnect cable can easily be 1 to 10 Khz.
John
Edit: Although I haven't had any comms with Gene in over a decade, I suspect he is not up to speed on what I just mentioned, so any vid on that topic I would certainly take with a grain of salt.
Where is the science to confirm your idea of a "break" frequency for the signal return path through the power cord rather than the shield?
It's actually bog standard EMC understandings. The discipline of EMC has a basic tenet: keep control over the total current and it's path.
If you search Tom Van Doren's teachings, he really goes into it in depth. It's in chapter 2, "Current routing and the path of least impedance", slides 2-4 and 2-12.
I had a drawing and explanation on this site, I believe it's still there, shows the path impedances.
John
Edit: I used all this when I designed the wiring system for the machine at work, and so far there have been no complaints. Now I'm helping the motion control guys as they get noise from PFM amps driving stepper motors due to coil to frame capacitance.
That's not much of an answer as it pertains to the typical audio systems that most people here have. You make a broad generalization that everyone has ground path issues with their stereo system without any proof of that being the case.
I stated facts. When a system has three prong plugs and is interconnected with rca's, the return currents of the signals will distribute based on the impedance of the paths at frequency. At 20-100 hz, a #14 or #12 ground is typically significantly lower in impedance than the shield of the RCA, the break frequency occurs when the ground loop inductance gets in the way.
If the resultant ground loop does not produce audible hum, most people believe there is no ground path issue. That is not necessarily the case, as the LF return path being via the ground cord has the capability of introducing haversine components into the signal chain when the amplifier is drawing significant power.
You seem to be trying to prove something, but you do not have the technical experience to properly discuss what you are arguing.
I do it for a living, but granted, what I've wired very successfully is 800 meters in diameter and quite in the thick of R&D science. I've also 4 decades of audio experience.
I'm more than happy to answer questions on this stuff, but would prefer the Q's and discussion be with less attitude. The links you've provided are not actually world renowned experts in this field. Good enough for laymen to understand, but certainly not the top dogs.
John
If it is attitude that is a concern, I think you should look inward instead. You consistently write posts where you claim to be the world expert on things. Even without a degree in engineering or physics you claim superior knowledge to those who do have college educations and degrees. Sorry, but I'm just not buying it regardless of what you do for a living.
JN,
Sorry to hear your degree was retracted!
I hope you Colleagues haven’t caught on to your lack of knowledge.
Knowing the power levels you play with, it is amazing by just luck you haven’t blown anything up, had a fire or killed folks. 😉
ROTFL!!!
Sorry to hear your degree was retracted!
I hope you Colleagues haven’t caught on to your lack of knowledge.
Knowing the power levels you play with, it is amazing by just luck you haven’t blown anything up, had a fire or killed folks. 😉
ROTFL!!!
Yah, I seemed to have missed that "you don't have a degree anymore memo.."
The only good thing about the pandemic has been I don't have to travel to give presentations or be there in person as part of review committees for the big machines. The holder of the purse strings requires reviews from experts at various stages of development, they get pretty antsy when the checks are a billion dollars or so...sheesh.
I really don't like work travel that much. Last time in Boulder, the connection at Baltimore was wiped out by storms all along the east coast, I had to drive from there home..
No big explosions....
Hey, the day is young.
John
I assumed that you don't have a degree, because you keep putting down those that do have one. And that is usually the behavior of someone who is not degreed but thinks that they are smarter than those who are. It is rare behavior for those who are degreed just out of mutual respect for one another.
Perhaps you would like to clarify the situation.
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