Copper foil

Palerider, Far from "hi-fi legend," skin effect at AC is well documented as variation in impedance against frequency that occurs at difference depths of a conductor. The effect becomes pronounced at frequencies above a few kHz. It's not true that signal travels only on the surface of the conductor, but it is true that the larger a conductor's diameter, the more skin effect causes audible frequency shift. This is why litz wiring was conceived.

Ribbons sound great because of reduced skin effect. However you are correct that adequate conductor guage is also significant. The 2"x .005" copper ribbons I'm using as speaker cables have a cross-sectional area of 6.45 mm2-- about the same as a 9awg round wire.

Before you start claiming that skin effect is significant above a few kHz do the calculations. The effect is vanishingly small in the kHz range. I speak as someone who works in the GHz range

Rather than explore relevant Bessel functions & Maxwell equations in a non-technical forum, I suggest that doubters spend $100 at McMaster-Carr for some electronics-grade copper of equivalent gauges in both formats & experiment. You will be surprised.

Regalma1 Wrote:

I speak as someone who works in the GHz range.

Others are probably speaking as someone who listens to music.

Cheers!
Robert
RSAD

I went from solid cord to ribbon. There is no looking back. Dynamics, depth, detail, and separation have never been better.