Directionality of wire

There is some confusion as to what the difference is between current and the audio signal. The audio signal is the electromagnetic wave. The current is traveling at the speed of electron flow in the conductor, which is virtually idle, to whit,

"Electromagnetic waves propagate in vacuum at a maximum speed of 299,792,458 meters per second . For a 12-gauge copper wire carrying a 10-ampere DC current, the speed of electric current (average electron drift velocity) is about 80 centimeters per hour or about 0.0002 meters per second."

The electromagnetic wave is the audio signal. There is no electromagnetic wave in the power cord or in the fuse where the power cord enters the amp. As I said previously, most audio frequencies travel within the IC or speaker cable wire per se, the skin effect being that very high frequencies travel nearer the surface (skin) of the metal conductor. And what carries the audio frequencies? The electromagnetic wave, of course!

There is no law saying photons can’t travel in copper. In fact it’s the physical non symmetry of the copper ITSELF that gives rise to directionality. Now, if anyone wishes to argue that "directionality" is due to electron speed differences (due to physical non symmetry of the wire) that give rise to resistance differences depending on directios I might actually consider going along with that.

geoffkait

There is no law saying photons can't travel in copper. In fact it's the physical non symmetry of the copper ITSELF that gives rise to directionality. Hel-loo!

>>>>>Indeed there is. The laws are called Maxwell's equations and were published in the 1860s. They are fully relativistic and form the basis for all electric, optical and radio technologies. In fact they are also used to calculate the skin-effect. As I stated above, any asymmetry in the copper can only affect the electron motion -- not the photons (electromagnetic fields and photons are one and the same).

If somebody is interested in the math of electrical energy flow in cables, this is a good article in Am. J. Phys. (it's possible to read the paper without following all the math):

http://depa.fquim.unam.mx/amyd/archivero/El_flujo_de_energia_de_una_bateria_a_otros_elementos_de_un_... 

sfroyen
geoffkait: There is no law saying photons can’t travel in copper. In fact it’s the physical non symmetry of the copper ITSELF that gives rise to directionality. Hel-loo!

Indeed there is. The laws are called Maxwell’s equations and were published in the 1860s. They are fully relativistic and form the basis for all electric, optical and radio technologies. In fact they are also used to calculate the skin-effect. As I stated above, any asymmetry in the copper can only affect the electron motion -- not the photons (electromagnetic fields and photons are one and the same).

>>>>as I already said the skin effect is simply that higher frequencies travel nearer to the outer surface of the conductor. And those frequencies are very high. Obviously, by inference, the lower the frequency the closer to the center of the conductor it will travel. How does that comport with the electromagnetic wave - the audio signal - traveling outside the conductor as you claim? Hint: it doesn’t.

If somebody is interested in the math of electrical energy flow in cables, this is a good article in Am. J. Phys. (it’s possible to read the paper without following all the math):

http://depa.fquim.unam.mx/amyd/archivero/El_flujo_de_energia_de_una_bateria_a_otros_elementos_de_un_....

That paper does not show that the electromagnetic field of the AUDIO SIGNAL travels outside the wire nor does it show that current travels outside the wire. What it shows is that *components* of the electromagnetic field can travel on the surface of the wire. We already know that a magnetic field induced by current traveling through wire and extends beyond the wire according to the right hand rule. (This is why it’s important to address the large magnetic fields produced by large transformers in audio systems with low frequency high permeability alloy.) The paper involves a battery connected to a wire so I’m not sure this paper even applies to an audio system. The paper also states there is energy INSIDE the wire and describes the mathematics of the electric field and magnetic field INSIDE the wire. See top of page 1.