Absolutely true, but hardly applicable to silicon audio transistors and circuit topologies. Start playing with compound or wide-band-gap semiconductors, and run them open loop and see how much the memory and trapping effects make you want to SMASH SOMETHING.
Electrons wiggle back in forth in + and - wires simultaneous, one direction on one the opposite direction on the other, then vice versa. It takes two to tango. The electrons wiggle back and forth at the rate of the instantaneous audio frequency whatever it happens to be at that instant. We know the drift velocity of free electrons in the cable is about one meter per hour. If you do the math that means electrons only travel about a millionth of an inch AT ONE TIME, on average. Net electron velocity is zero, that part is pretty obvious.
The tricky part is figuring out why all the free electrons along the entire length of the cable change direction at the very same instant.
It is never too late to read a good book. I recommend Feynmans Lectures On Physics.
https://www.feynmanlectures.caltech.edu/
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They don't. If you close a switch at some point along the cable, that information can only propagate down the cable at the speed of light in that medium. Not exactly the same as 'at the very same instant.'
Only point is, probably be good in a snake oil thread to try to keep explanations accurate as is reasonably practical. Otherwise slightly dramatized claims of scientific truth could potentially slide a little into snake oil territory.
He might ask if the cable was an LTI uniform transmission line with the shield connected at both ends?
The speed of light in a cable is instantaneous in my book. A trillionth of a second or whatever.
I guess he lived too early to respond to this invention of the audiophools
As EEs we have to deal with it all the time. The relationship between an antenna's length and its resonant frequency is highly dependent on the propagation velocity along the line. Same thing for stub-tuned transmission lines. You want to sell your own brand of snake oil to unwary readers, or try to get things right?
The problem I have is that some newbies may take your words literally. If that happens you're not doing them a favor by teaching them something that isn't accurate.
Talking about nit picking, can’t see the forest for the trees. If Feynman were around today and heard my explanation I’m sure he’d agree with me.
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Probably what he would say would depend on the audience he was speaking to. A class at an elementary school probably isn't at the stage of being able to comprehend some technical things. OTOH, if he were giving at talk at a university he would probably try to be exceedingly accurate.
So, what does the audience consist of here? This supposed to be an audio electronics and physics technical forum. Some of the people here working with digital audio are working with clock frequencies up around 100MHz. Harmonics of the clock edges may easily extend up into the GHz region. At that point we are seriously talking about billionths of a second.
Why shouldn't we just tell it like it really is? We are not helping people here by oversimplifying like they are still little kids.
So, what does the audience consist of here? This supposed to be an audio electronics and physics technical forum. Some of the people here working with digital audio are working with clock frequencies up around 100MHz. Harmonics of the clock edges may easily extend up into the GHz region. At that point we are seriously talking about billionths of a second.
Why shouldn't we just tell it like it really is? We are not helping people here by oversimplifying like they are still little kids.
Not complicated, just deep. Understanding begins with learning. Its like an onion. First counting, then addition, followed by multiplication, division, powers, roots, geometry, algebra, calculus, .......... That's just for math, similar onions for physics, chemistry, engineering, .......
Once one level of understanding is mastered those that came before are no longer complicated.
Once one level of understanding is mastered those that came before are no longer complicated.
Absolutely. I had one good maths teacher at age 13 and this was the great secret he shared with us; a secret too many teachers seem to keep to themselves.
Hmmm, wasn’t it Feynman who observed, “anyone who thinks he understands electrify probably doesn’t?”
Light does slow down a bit in a light pipe cable, but it's not like I'd ever notice it.
Actually we do notice it. It’s important. My glasses would be useless without.
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