Yes, oxidation may theoretically change inductance of a cable, thereby changing the energy 1/2LI^2 stored in the cable. Same can be said for inter cable capacity change for the 1/2CV^2 energy.
However I fail to understand why a minor but stable oxidation would be converted into noise by an also stable but slightly changed proximity effect for a certain frequency, or even worse into distortion.
So all in all, sorry for my ignorance, but maybe you could enlighten your thesis with a simple example.
Hans
Look up the wiki page, same figure I mentioned to Bonsai. The currents "Iw" cross strands.
Jn
If the oxide contact surfaces present as really poor diodes, or better stated, nonlinear conduction paths, the faraday currents will be nonlinear. In addition, the dissipation caused by the poor and nonlinear conduction of the faraday currents will be present.
I see no mechanism to change the capacitive energy storage as a consequence of conductor strand contact nonlinearities however.
In the entire discussion, it is important to consider level of effect. A cable that nonlinearly trashes half the inductively stored energy in the zip is still trashing a rather small quantity. 100 watts into a ten ohm load with a ten foot zip can only trash 10 amps times ten amps times one microhenry.
Or, 100 micro joules. The question would be one of spectra and phase of the energy that is trashed.
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OK, but what about the case in point which was line level STP cable? under 10v with hopefully at least 20kOhm load at the terminating end?
Practically, on a 70-100 strand 5mm diameter speaker cable, what effect will this have up to 100 kHz?
Why on an oxidized strand would Iw be messed up enough to have such an effect ( is audible)at what are in the big scheme of things quite low frequencies? Could we measure the effects you mention over the frequencies of interest?
I suspect the discussion is being steered toward mechanisms to cause ITD in speaker cables. 😉
Scott... 😀
Yes to concur with others - the question is not so much whether these effects exist, more - are we talking anything that could possibly be enough to be audible?
What are the actual numbers, JN?
Yes to concur with others - the question is not so much whether these effects exist, more - are we talking anything that could possibly be enough to be audible?
What are the actual numbers, JN?
My previous post detailed the level of effect in terms of stored magnetic energy.
The inductive change is easily measured but there is a caveat to that. Not too many people can measure inductance that accurately or repeatably, it is almost an art. Also, most meters will only present Ls and Rs terms. There are no inductance meters well equipped to determine non linear Rs, they can only present the equivalent resistance.
A 12 AWG zip is quite heavily into proximity at 10 to 20 kHz, most em packages can show that. Heck, it can be googled as well.
Jn
I did provide numbers. Here's more.
With 100 watts delivered to a load, 100 micro joules is in question.
10e-8 referred to signal, 10e-6 referred to one watt.
However, a ten kHz sine at 1 watt has 10e-4 joules energy per cycle. One watt tweeting with 100 watts midrange is consistent with existing audio speakers.
The numbers are firmly within the ballpark such that a simple discounting of possible audibility would be unfounded.
Specific tests would be needed to discount audibility as well as to prove it can be heard.
Oh, and I've never heard this effect in any stereo I've used. I have heard current modulated noise before, but I suspected it was just bad components in my Aaron Gavin equalizer.
Jn
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Google proximity effect zip cable. You will find many very colorful pictures depicting the current distribution...just be careful, as the pics showing current concentrating away from the other conductor are same direction currents, some captions don't explain that. Trust the ones with opposite currents.
Recall I stated a speaker cable is high Z feeding a low z load, that system is current/inductance dominated. An STP driving 20kohm is voltage/capacitively dominated.
Jn
Which is why I am confused as we are discussing balanced interconnect cables (or were trying to amongst the flying peanuts)
Mountain man bob is using really heavily oxidized monster zip cable as a balanced interconnect?? Shame on him..😉
Jn
Oh great. A discussion about low level interconnects with a complete disregard of amplifier physical topology, ignoring all aspects of ground loops. Wonderful..
I put that analysis in my gallery 16 years ago IIRC. Actually, December 2013.
Sigh.
Jn
All cables have L and C, and all form physical ground loops. Control of all currents and where they flow and return is many times woefully neglected.
I've even had to correct that transformer guy, forgot his name.
And I don't include fiber..just the metal cables.
Jn
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