That reminds of a documentary on NetFlix... a guru in India explained that the unwashed, uneducated people do not want enlightenment. They just want magic.
-RNM
Not sure what you want to prove or state with these ridiculous numbers. You are again talking and generalizing pathological cases, yet another type of *UD.
300ppm is perhaps for very bad carbon composition resistors (normal is around 100ppm), carbon film are under 50ppm and I'm having a very hard time finding any metal film resistor with a VC over 10ppm.
P.S. Thick film resistors are in fact good quality (that is, not worse than) carbon film resistors.
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Let's see, Pavel asked what were non-ohmic loads, obviously loudspeakers are. The AES standard for power handling rates it at the power level where the impedance doubles. At that level no changes seem to occur the next time the loudspeaker is used. Some of that change is from the voice coil heating but some must be from other causes since just beyond that level damage occurs. Some of the change is due to the cone suspension becoming a non-linear force as the excursion reaches extremes and of course with under hung voice coils it is due to the obvious change in magnetic gap/voice coil position. Then there are changes due to cone breakup. So by the definition of power handling a loudspeaker is a non-ohmic device.
The classic example but no longer common is the neon lamp. It has a negative resistance region which is why it can be used in relaxation oscillators. Same thing with some specialized semiconductor diodes.
Then there are devices such as varistors or even Zener diodes which clearly do not follow Ohm's law.
Now as to resistors you are appear at times to be confusing temperature coefficient with all forms of nonlinear behavior. Carbon composition resistors according to the data sheets may have a temperature coefficient of 450 PPM. Although 25 PPM thermal coefficients are common after my paper was published showing an easy non temperature measurement method to quickly read out temperature coefficient new better performance secret formulas have been produced. Now voltage coefficient is often a different issue. In wirewound resistors there is a significant issue of how the leads are welded to the resistance wire. A similar issue on most other types where the leads connect to the resistor body.
Then we could look at self induced thermoelectric effects.
As to thick film resistors no one aware of the issues uses them for precision work.
Of course Pavel's question was about loads not just resistors, devices made to approach Ohm's law as closely as possible.
So the question becomes are you not fluent in English or just lack comprehension? You already claimed to have read the article on resistor distortion, so why do you make these claims?
The classic example but no longer common is the neon lamp. It has a negative resistance region which is why it can be used in relaxation oscillators. Same thing with some specialized semiconductor diodes.
Then there are devices such as varistors or even Zener diodes which clearly do not follow Ohm's law.
Now as to resistors you are appear at times to be confusing temperature coefficient with all forms of nonlinear behavior. Carbon composition resistors according to the data sheets may have a temperature coefficient of 450 PPM. Although 25 PPM thermal coefficients are common after my paper was published showing an easy non temperature measurement method to quickly read out temperature coefficient new better performance secret formulas have been produced. Now voltage coefficient is often a different issue. In wirewound resistors there is a significant issue of how the leads are welded to the resistance wire. A similar issue on most other types where the leads connect to the resistor body.
Then we could look at self induced thermoelectric effects.
As to thick film resistors no one aware of the issues uses them for precision work.
Of course Pavel's question was about loads not just resistors, devices made to approach Ohm's law as closely as possible.
So the question becomes are you not fluent in English or just lack comprehension? You already claimed to have read the article on resistor distortion, so why do you make these claims?
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I thought you were talking about voltage coefficient, do you have some sample numbers for that for common types?
Not with me. But virtually all the high quality resistors I measured show almost none. I can post some tomorrow. However as the discussion was on loudspeakers as loads...
No, I don’t confuse anything. As others also noted, you were specifically talking about about the voltage coefficient of resistors and you quoted a number of 300ppm:
Now you move the target to the temperature coefficient, pepper an insult, then claim you have no data about the voltage coefficient, and that you were unable to measure any:
Do you really think you are talking here with a bunch of ADD idiots?
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Ed calm down, I know of no material where sigma (conductivity) is a fundamental constant. The charge on the electron (q) does not vary with temperature or pressure, etc., neither does time. Ohms law is not and never was statement of a relationship between fundamental physical constants.
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Just one. I already showed a resistor measurement above 300 PPM voltage coefficient.
You could also try placing speakers asymmetrically
What’s that got to do with a phase matching amp?
Well some of the things he’s saying kindly make sense to me as phase balancing is something I battle every time I make a change ......if he can really do the things he says it’s definately got my attention.
If not then at least it’s an attempt.
I think even ohms work was described by his piers as ‘a web of naked fancies’ ?
And I said that’s a pathological case that cannot be extrapolated, it’s simply *UD.
All this in the name of keeping up you war against physics and in particular Ohm’s law. It would be funny if it wouldn’t be sad.
This is an ad-hoc casual definition for “ohmic device”. Nothing to do with Ohm law, which does not apply to “ohmic devices” only. The general Maxwellian form of Ohm’s law J=sigma*E does not make or use any assumptions about sigma, which could be a function of any number of variables, even a tensor e.g. in the presence of a magnetic field, see the Hall effect.
Quote with comment:
"{A} physicist who professed such ideas was unworthy to teach science."
German Minister of Education, reacting to Professor George Simon Ohm's discovery of the mathematical relationship between the intensity of electric currents and the resistance of the circuits through which they pass, 1827.
'The Experts Speak' p. 293
See, even good ideas are often suppressed by 'experts' for a certain time.
"{A} physicist who professed such ideas was unworthy to teach science."
German Minister of Education, reacting to Professor George Simon Ohm's discovery of the mathematical relationship between the intensity of electric currents and the resistance of the circuits through which they pass, 1827.
'The Experts Speak' p. 293
See, even good ideas are often suppressed by 'experts' for a certain time.
Bob, if you're not confused you're not paying attention!
I'm not sure what you mean by "phase balancing". When a voltage is applied to a reactance, the resulting current through the reactance has a phase difference from the voltage. Period.
Now Joe is putting a reactive impedance network between the amplifier and the speaker, and he says that makes the current through the amp, or perhaps through the conjugate load, more closely match the phase of the voltage, or something like that. Of course, this has diddly squat to do with the phase of the current through the voice coil.
Now if Joe can show that his conjugate network "predistorts" the voltage/current phase relationship in such a way that the voltage applied to the speaker voice coil is now in phase with the current through the voice coil, then I am all ears. So far he has not shown anything remotely like that.
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