Silver plated copper

Skin effect is frequency dependent and negligible at audio frequencies.

This is not exactly true, although it is common to think of it that way. So common that the fundamental was lost.

One might say that the skin effect consideration is affected by the wire or path of transmission, and that the formula we use is specifically tied to ’wire’, or lengths of pathway that are longer than they are wide..

Then that formula is ’made up’, regarding ’black box’ analysis of AC flow in said geometry of the flow.

Or, that the phenomena of skin effect, has been applied to transmission lines, the formula is created for application to transmission lines in engineering and design.... and then people take this simplistic single point and misapply and call it skin effect, when in fact, it is not. Far from it.

Skin effect is indicative of a greater consideration than the simplistic transmission line formula suggests. That the complexity of Skin effect and it’s origins were and are ’black boxed’ for simplistic engineering work.

That the black box is a far bigger thing than the simple formula or it’s generic and common application.

What is in the black box of skin effect?

There is no reason why you want to use 2 different conductors (of any type) in a cable. In fact I am also not in favor of any plating on surfaces which attach to equipment. FWIW.

Many textbooks on electrical engineering have the word "theory" in their title and I consider skin effect to be one.

Many topics in science use the word "theory."


It does not mean unproven. It means there is an explanatory model.


For instance, the "theory" of gravity. It is not up for ephemeral debate, nor is the "theory" of relativity or flight. While both the theory of gravity and relativity continue to be improved upon, they are the equivalent of "scientific fact."


However, going back to skin effect, it is real but I’ve never seen any models which explain why this would matter at audio frequencies with common conductor sizes.


Best,

E

There is the theory that much of the audio signal - I.e., the electromagnetic wave - travels outside the conductor which, if true, could explain why the skin effect is audible at audio frequencies.