Cat7 (shielded or not) can run 100m at 600Mhz. Kinks in the cable can reduce the bandwidth. Never seen one that's directional.
I suppose there is a difference between "the cable is directional" and "the system sounds different depending on the orientation of the cable". The former is in conflict with alternating current but the latter may have more possibilities.
Hmm. A 12 AWG zip cable will exhibit proximity effect in the audio band. As such, since it is stranded, the conductors will alternate being close to the partner conductor, and far. For proximity effect to take effect, there has to be strand to strand conductivity. If there is no interstrand conductivity, you have litz, which does not exhibit proximity effect at the cable level.
If a zip cable is so corroded that interstrand conduction is compromised, proximity effect has to cross very bad strand interfaces.
If we take a 20 foot length of #12 zip, bag it in a ziplock with some Clorox, put it at 90C for a few weeks until the green is total, then test..(I assume no vacuum pumping would be needed).
First, spectra from 20 to 20k, look for noise floor. Push an ampere.
Then, split the zip, spacing the conductors 3 inches apart the entire length. Repeat the spectrum.
In the first test, you are looking for proximity effect based interstrand conduction through bad contacts. In the second, you've removed proximity effect.
Oh, keep a second length as reference.
Jn
How do you generate much inter-strand potential? I'm having a hard time finding data on the conductivity of the green family of copper compounds (my CRC is in storage).
How does one get a good ground connection. Is it by laying your earth spike flat and covering it with a 6 foot heap of dirt, or digging a six foot deep hole and burying it. I guess that could apply to the box of dirt as well.
You can nerd out on even the most mundane thing. https://www.galvanelectrical.com/pdf/NavigatingGroundRodMaze.pdf
At 20khz, most of the current is in the inner half of the conductor closest to the opposite conductor. For a twisted stranded, that requires cross strand "traffic" (just channeled Hendrix). I would expect a battle between higher resistivity with fewer conductors, and crossing strands.
I'm sure there's probably some optimum effect thing, but I do not know if it is even measurable at the resolution available.
And what does cyclic redundancy check have to do with finding compounds?😉
Jn
No.
Earthing is what you do with a rod in the dirt. It must be done at your service entrance. It's sole purpose in life is to keep your electrical system fairly safe from lightening strikes on or nearby.
It is NOT intended as a reference potential for a sound system. Nor is it actually a low resistance. Code was, put one in, if it's below 25 ohms, done. If above, put in another...done. No measurement, just done.
A earthing rod placed anywhere else around the outside of the house with the intent of providing a "quiet ground" can be extremely dangerous to the house and occupants. A strike on or nearby can cause extreme voltage potentials in the house.
What we generally refer to as grounding on the other hand, is the "bonding" of a sufficiently sized conductor from metal things in the house to the grounding conductor of the electrical service, connectivity all the way back to the service panel, where ground and neutral are tied together, over to the plumbing pipe feeding the house, outside to the earthing rod, and up to the neutral so the service feed. Note this is east coast USA only.
The grounding in the house is only there to trip the circuit breaker in the event a hot conductor makes a connection to a chassis. It must keep chassis potential below 50 volts until the breaker trips. An earthing rod WILL NOT DO THAT!!!
Never substitute an earthing rod for equipment ground.
The grounding system in your house is NOT a clean reference potential that can be used for audio quality ground. You have to establish a reference potential between the equipment.
Needless to say, a box of dirt is not a ground, nor is it an actual earthing potential. It is a box of dirt.
Plant a flower in it.
Jn
Ps in point of fact, every second or third telephone pole here has an earthing rod. It ties to the pole neutral. Our service has an auto transformer, hv wire at the very top. It is estimated that 2 to 5% of the service feed current is carried by the earth, not the neutral wire on the pole. As a result, there is a voltage gradient in the soil.
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I figured you would know, I suppose these days most don't. My copy is the 1964 edition my father gave to me as a high school graduation present. What a drag I missed out by 1 year on the massive 3400 page edition.
Last time I used one was (IIRC) to get copper resistivity and heat capacity from 1.8K to 400C. Was working out a final conductor temperature for #14 to #28 wires subjected to a 400 amp peak several second decaying pulse.
Wrote a program, broke time into microsecond slots, used recursion.
Wrote a paper, had a friend proof it. He converted the entire math package to analytical equations. Results were identical, only I couldn't understand the math anymore.😱
Jn
Ps. I couldn't tell...did your father love you..or hate you?😀
Um, my remark was supposed to be lighthearted humor.🙁 It's not everybody who is gifted the CRC.)
I woulda thunk maybe a POS car.
My dad gave me a vw beetle engine at 12, fully disassembled, no manual.
Coolest erector set a kid could ask for.
Jn
Since your citing types of cognitive bias you are doubtless aware you demonstrate being caught in a strong cognitive bias yourself. Namely belief bias.
Belief bias An effect where someone's evaluation of the logical strength of an argument is biased by the believability of the conclusion.
This is a common source of anti-scientific dogma, somewhat amusing pedalled by individuals who claim to be scientific.
Ignoring the bit about cable sound, my experience has been that musicians, on the whole, aren't particularly interested in hi-fi reproduction.
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