The Physics of Electricity

“When a cable carries a pure tone, perhaps a sine or square wave, then frequency and time are interchangeable, meaning that the only distortion of the signal would be attenuation. But music is far from a pure tone, and is a complex flood of frequencies in the 20 Hz-20 kHz range. When you send multiple frequencies down a cable, you introduce the possibility of time-based distortion, as different frequencies are affected differently by reactive variables such capacitance and inductance. Our ears are quick to hear the deterioration in fidelity based on frequency-arrival time and phase coherence.

To compound the issues, audio frequencies lie in an awkward electromagnetic region for conductors. Don’t forget that audio frequencies are at the bottom end of the spectrum; these are among the slowest, longest wavelengths of electromagnetic energy we harness.

Electromagnetic wave propagation: what exactly is the “signal”?

To understand why cable design has an effect on a signal in the first place, it’s important to understand exactly what this “signal” is, and how it “travels” along the cable.

Visualize the wire as a tube that’s the diameter of a set of marbles which you can push down the tube; the marbles are the electrons. Electrons don’t move without also causing electromagnetic fields, so now imagine a donut with its hole centered around this marble tube. This is the magnetic wave (B field). Now, take a bunch of toothpicks and stick them around the outside of the donut—this is the electric field (E field) produced by the moving electrons.”

The electromagnetic field is strongest nearest the wire, decreasing with the square of the distance moving out away from the wire.

Belden has applied all their design and manufacturing capabilities to high-performance audio cables for the audiophile market. Engineer Galen Gareis is the lead on the Iconoclast line of high-performance audio cables, and is happy to explain the science behind cable design.

Let’s look at the first electricity article published on the PS Audio website more closely. Here are two excerpts (in quotes) along with my comments.

“Also as we saw, the “signal” moves down the wire’s outer circumference, and not inthe wire. Therefore, the velocity of propagation of the signal (versus the velocity of the actual electrons) is determined by the dielectric or insulation material that the electromagnetic wave is predominantly traveling through. The slowing effect of the dielectric varies with frequency, throwing another variable into velocity of propagation—but giving us a way to play with it.”

>>>>>The signal moves (mostly) inside the wire. If it didn’t wire would not be directional and there would be no differences among conductors, or among purity of the metals. If it doesn’t make sense it’s not true. Furthermore, the signal doesn’t contain frequencies. It’s not the music waveform. The velocity of propagation is constant for a given conductor material, e.g., copper. That velocity is a high percentage of the speed of light.

“In one tested cable, the speed of a 20,000 Hz signal is about 110-million m/sec. The speed of a 20 Hz signal is about 5-million m/sec, or about 22 times slower. In other words, the impedance of a cable rises as we lower frequency due to the VP dropping, and capacitance value. Each is determined by the dielectric and the design spacing.”

>>>>>The “audio signal” is not a frequency nor does it have frequency components in it. The “audio signal” is a current, an electromagnetic wave. It is not (rpt not) the music waveform. We also know that the signal (electromagnetic wave) travels at different velocities in different materials. In copper the electromagnetic wave travels at a high percentage of the speed of light. That’s because the signal is composed of photons. In free space the electromagnetic signal, e.g., satellite signal, travels at the speed of light. We also know the drift velocity of electrons in copper is a constant. It can be calculated. It’s something like a meter per hour. And the direction of electron drift is the same as the direction of current, which alternates.

determined by the dielectric or insulation material

ascertain or establish exactly, typically as a result of research or calculation

Ralph Morrison

"The laws I want to talk about are the basic laws of electricity. I’m not referring to circuit theory laws as described by Kirchhoff or Ohm but the laws governing the electric and magnetic fields. These fields are fundamental to all electrical activity whether the phenomenon is lightning, electrostatic display, radar, antennas, sunlight, and power generation, analog or digital circuitry.

These laws are often called Maxwell’s equations. Light energy can be directed by lenses, radar energy can be directed by waveguides and the energy and power frequencies can be direct conductors. Thus we direct energy flow at different frequencies by using different material.

For utility power the energy travels in the space between the conductors not in the conductors. In digital circuits the signal and energy travel in the spaces between the traces or between the traces and the conducting surfaces.  Buildings have halls and walls. People move in the halls not the walls.  Circuits have traces and spaces, signals and energy moves in the spaces not the traces."

Sound System Engineering 4e

"In physics, the Poynting vector represents the directional energy flux (the energy transfer per unit area per unit time) of an electromagnetic field. The SI unit of the Poynting vector is the watt per square metre (W/m2). It is named after its discoverer John Henry Poynting who first derived it in 1884. Oliver Heaviside and Nokolay Umov also independently discovered the Poynting vector. 

... For example, the Poynting vector within the dielectric insulator of a coaxial cable is nearly parallel to the wire axis (assuming no fields outside the cable and a wavelength longer than the diameter of the cable, including DC). Electrical energy delivered to the load is flowing entirely through the dielectric between the conductors. Very little energy flows in the conductors themselves, since the electric field strength is nearly zero. The energy flowing in the conductors flows radially into the conductors and accounts for energy lost to resistive heating of the conductor. No energy flows outside the cable, either, since there the magnetic fields of inner and outer conductors cancel to zero."

Poynting vector - Wikipedia

Skin effect is the tendency of an alternating electric current (AC) to become distributed within a conductor such that the current density is largest near the surface of the conductor, and decreases with greater depths in the conductor. The electric current flows mainly at the "skin" of the conductor, between the outer surface and a level called the skin depth. The skin effect causes the effective resistance of the conductor to increase at higher frequencies where the skin depth is smaller, thus reducing the effective cross-section of the conductor. The skin effect is due to opposing eddy currents induced by the changing magnetic field resulting from the alternating current. At 60 Hz in copper, the skin depth is about 8.5 mm. At high frequencies the skin depth becomes much smaller. Increased AC resistance due to the skin effect can be mitigated by using specially woven litz wire. Because the interior of a large conductor carries so little of the current, tubular conductors such as pipe can be used to save weight and cost.

In the autumn of 1884, Károly Zipernowsky, Ottó Bláthy and Miksa Déri (ZBD), three engineers associated with the Ganz factory, determined that open-core devices were impractical, as they were incapable of reliably regulating voltage.[10] In their joint 1885 patent applications for novel transformers (later called ZBD transformers), they described two designs with closed magnetic circuits where copper windings were either wound around a ring core of iron wires or else surrounded by a core of iron wires.

I know there is difference between a Sony receiver and Krell FPB amplifier

...technology that optimally aligns the crystals while reducing the number of crystal-grain boundaries resulting in a tremendously efficient conductor.


Straight OCC’s benefits are its larger “fibrous” crystals in which one dimension is longer than the other two so as to create as few crystal junctions as possible.

Incorporated into selected Furutech products, NCF features a special crystalline material that has two ‘active’ properties. First, it generates negative ions that eliminate static. Second, it converts thermal energy into far infrared. Furutech combines this remarkable material with nano-sized ceramic particles and carbon powder for their additional ‘piezoelectric effect’ damping properties. The resulting Nano Crystal² Formula is the ultimate electrical and mechanical damping material.

Created by Furutech, it is found exclusively in Furutech products. No other manufacturer goes to the expense and effort that Furutech does to develop and produce high-end audio accessories and cables, and NCF is a cumulative result of 30 years of research and development of Pure Transmission high-end audio grade products.

Furutech has produced decades of unrivaled innovation within the audio industry. We have enabled listeners all over the world to get closer to their favorite music by making it sound as crystal-clear as possible. We have accomplished this enviable feat through careful research based upon solid scientific principles, and exhaustive listening tests to confirm those results.

For example, we have pioneered the use of many revolutionary technologies in our legendary line of Furutech products—the Floating Field Damper, the Two-Stage Cryogenic and Demagnetization Process and many, many others. Now we’re set to transform the audio industry with crystals.

These aren’t “magic” crystals, mind you, but a new crystallized material that actively generates negative ions to eliminate static and converts thermal energy into far infrared. There is nothing mysterious about the way these crystals work—quite simply, they improve audio performance in a very specific and measurable way.