Scientific Perspective - An Independent Study

Stephen Hendrick sent us the below email:

"Mike, I have had your speaker wire (SP6) and interconnects (MA4s) in my system for 1-2 years and very happy with them. I asked a friend who is a senior guy in a company making components for satellites if there was something to your SSI Technology approach and he said that he recalled a paper from some time ago that essentially backed up your claims.

As a research guy, I just used ChatGPT to look for skin & phase effect research and stumbled into a number of them that might be of interest to you.

Several of us who can claim this audio thing as a hobby, have gotten together and done A:B comparisons with the Morrow cables against some pretty expensive competition and your wires were at least their equal.

Since there would seem to be real science that backs up your approach it would be refreshing to get it out in the open. Let me know."

He then sent us the following...

You Asked ChatGPT: 

Is there science behind the strategy that Morrow Audio uses in creating its interconnects and speaker wires?

ChatGPT said:

Morrow Audio employs a design approach they term SSI Technology—Solid-core, Small-gauge, Individually insulated conductors—in their interconnects and speaker cables. This methodology is intended to enhance audio signal integrity by addressing common issues found in traditional cable designs.

Solid-Core Conductors: Unlike stranded wires, which consist of multiple small wires twisted together, solid-core conductors are single, continuous strands. Stranded wires can cause the audio signal to jump between strands, potentially leading to phase distortion. Solid-core conductors aim to provide a more direct path for the signal, reducing such distortions.

Small-Gauge Wires: Utilizing smaller gauge wires is intended to mitigate the "skin effect," where different frequencies travel at varying depths within a conductor. In larger gauge wires, this can lead to phase and timing errors. Small-gauge wires help ensure that all frequencies travel more uniformly, promoting accurate sound reproduction.

Individual Insulation: Each conductor is individually insulated to minimize energy absorption and release by the dielectric material, which can cause signal smearing and distortion. By reducing dielectric interference, the cables aim to maintain the purity of the audio signal.

These design principles are grounded in established electrical engineering concepts related to signal transmission. Reviews of Morrow Audio's products, such as those in The Sound Advocate, have noted that their cables exhibit characteristics like enhanced dynamics and tonal accuracy, suggesting that the SSI Technology contributes positively to audio performance.

However, it's important to recognize that the field of high-end audio cables includes diverse opinions. Some enthusiasts and engineers debate the audibility of differences attributed to cable designs, emphasizing the subjective nature of audio perception. While Morrow Audio's design strategies are based on scientific principles, individual experiences with their cables may vary depending on specific audio systems and listener preferences.

You said:

What is the skin effect and what is phase distortion?

ChatGPT said:

Great questions! Both skin effect and phase distortion are real electrical phenomena that can impact audio signal transmission, especially in high-end or long-run applications like speaker cables and interconnects.

Skin Effect

Definition:
The skin effect is a phenomenon where alternating current (AC) tends to flow more on the outer surface (or "skin") of a conductor as the frequency increases.

Why it matters in audio:

• In audio cables, higher frequencies (like treble) may travel more toward the outside of the wire, while lower frequencies (bass) are distributed more evenly.
• This can cause uneven signal transmission across frequencies, especially in thicker conductors.
• Using smaller gauge wires (as Morrow Audio does) can minimize this effect because the current can more easily occupy the entire cross-section of a thinner conductor.

Visual analogy:
Imagine people running through a hallway. At low speed (low frequency), they can fill the whole hallway. But at high speed (high frequency), they tend to hug the walls and avoid the center.

Phase Distortion

Definition:
Phase distortion happens when different frequencies in a signal arrive at slightly different times at the output. This alters the timing relationships between them, which can affect the clarity and realism of the sound.

In cables, phase distortion can be caused by:

• Differential propagation speeds (some frequencies move faster/slower)
• Dielectric absorption (the insulation temporarily absorbs some signal energy and releases it slightly delayed)
• Inductance and capacitance mismatches

Why it matters in audio:

• The timing between frequency components is critical to the perception of transients (like drum hits), spatial cues, and detail.
• Even tiny phase shifts can impact the soundstage and imaging in high-fidelity systems.

 Bottom Line

• Skin effect can lead to frequency imbalance.
• Phase distortion can lead to timing smears or loss of clarity.
• Both are more noticeable in longer cable runs or with poorly designed cables, which is why audiophile companies like Morrow Audio focus on conductor geometry, insulation, and gauge to minimize them.

If you want, I can show you some illustrations or examples of how these effects appear in waveforms.

You said: Yes, please do.

ChatGPT said:

Wave with Skin Effect (High Frequencies Attenuated)

Here's a visual breakdown of how skin effect and phase distortion can alter an audio signal:

1. Top Plot – Pure Sine Wave: This is a clean, undistorted signal composed of a 5 Hz sine wave—ideal audio transmission.
2. Middle Plot – Phase Distortion: Here, a high-frequency component (20 Hz) is added with a phase shift. This alters the waveform’s shape, simulating how frequencies can arrive out of sync—leading to a smeared or "off" sound.
3. Bottom Plot – Skin Effect Simulation: The same low and high frequencies are combined, but the high-frequency component is weaker. This shows how skin effect can roll off higher frequencies, dulling the signal’s clarity and sparkle.

You said:

In wire cable design and construction, what is the best way to reduce or eliminate the skin effect and phase distortion? For context, see the strategy that Morrow Audio uses in creating its component interconnects and speaker wires?

ChatGPT said:

Great context—since you're referring to Morrow Audio’s design philosophy, let’s dig into how their strategy aligns with general engineering best practices for minimizing skin effect and phase distortion in audio cables. Here's a breakdown of what works and why in wire cable design.

 1. Reducing Skin Effect

As frequency increases, current moves toward the outer surface of a conductor. To counteract this:

 Use Smaller Gauge (Thin) Conductors

• Why it works: In thin wires, there's less "depth" for skin effect to manifest, so current uses nearly the entire cross-section even at higher frequencies.
• Morrow's application: Their cables use multiple small-gauge, solid-core conductors.

 Litz Wire Construction

• What it is: A bundle of individually insulated strands woven in specific patterns.
• Why it works: Forces current to distribute more evenly among strands, reducing skin and proximity effects.
• Note: Morrow does not use traditional Litz wire but achieves similar benefits by using parallel insulated strands.

 Avoid Large Solid Conductors

• These are more susceptible to skin effect, especially at higher audio frequencies. Morrow Audio uses small gauge wires, each the size of a human hair.

 2. Reducing Phase Distortion

Phase distortion stems from frequency-dependent timing shifts. Here's how to mitigate it:

 Solid Core Conductors

• Why it works: Stranded wires can introduce random micro-jumps in current path, adding microscopic time delays.
• Morrow's strategy: Uses solid-core wires to ensure a consistent signal path and timing.

 Minimal Dielectric Interaction

• Use air or low-permittivity insulation: Dielectric materials absorb and slowly release energy, distorting the waveform.
• Morrow’s insulation: They use cotton, which has a low dielectric constant and minimal absorption.

 Geometry and Conductor Spacing

• Carefully spaced conductors can control capacitance and inductance, which otherwise cause phase errors.
• Morrow arranges their wires in an unshielded format for interconnects and speakers to preserve timing integrity.

 Avoid Shielding on Speaker Cables

• Shielding can introduce capacitance and reflections if not done properly. Morrow avoids shielding on speaker cables but shields phono cables where EMI is more of an issue.

 In Summary – Best Practices Aligned with Morrow’s Approach