Perfect Surface Copper?

The only place I see this phrase on the internet is on AudioQuest’s website. Is this a real thing, or is it just a marketing term for something more banal?

Sounds like a euphemism for very clean low impurity copper. Was going to say BS but there’s ususlly a kernel of truth to most claims (and conspiracy theories)

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All manufacturers you’d want to buy cables from are using high purity, oxygen free copper in their copper cables. Honestly, good quality cables today are differentiated more by cable geometry and choice of insulation materials than the quality of the conductor.
Bottom line: if Audioquest cables sound great in your system ignore marketing buzz phases like perfect surface copper and just enjoy!

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Take a look over on the Cardas site. They distribute copper wire to other companies for cable assembly. They have some good info on their wire.

We state that we have it, so no one else does?

Wire mill are millions and millions of dollars. The best technology for continuous drawn copper is well know. Yes, that includes ETPC, OFHC and OFE. Only UPOCC uses a batch proces and small VOLUME processing.

Current state of the art induction furnaces keep O2 to hundreths of what it was a few decades ago. Contaminants are gold, silver and other metals. Hardly cigarette butts. Modern drawn copper can meet -30 dB RL (Return Loss) or 1/1,000 reflection of the signal off the cable structure and the load at frequencies as high as 8 GHz. This is a measure of wire AND insulation perfection.

Last I checked, Audio is well below 8 GHz, and we don’t exhibit a steady state transmission line where RL is an issue. The EM, Electromagnetic Wave, travels OUTSIDE the copper structure, not in it or even “on” it but around it (magnetic wave) or radially out from it (electric wave).

Yes, the current or moving electrons that make the phonon’s that comprise the EM wave through superposition, is in the copper but not the EM wave itself. Each individual phonon, where ever it is in the wire, adds to all the other phonons to create the final EM wave properties,

The lower the frequency the less RL impacts the EM wave. And, the less the wire “surface” is an issue as more phonon signal travel “in” the wire than “on” it.

The phonon’s race down the wire at the dielectrics velocity of propogation at a given frequency. The electrons move from valence band to valence band far, far slower. We don’t “listen” to the electrons but the phonons created by moving electrons that comprise the EM field.

As a matter of fact, the BEST way to manage wire for audio is to improve the wire’s efficiency by making it smaller to force the higher frequencies to travel THROUGH the entire wire structure. Many small wires of the same DCR verses one big wire pay’s dividends as the internal impedance of the wire drops with smaller and smaller wire. Thus, small wire is more efficient and has a lower and more consistent resistance at all frequencies. This can be measured.The problem, is what to do with all those wires such that L and C aren’t becoming a problem if wemath the R value. Designers have to manage the entire problem, not parts of it, to make leading edge cable.

The biggest difference we can truly measure in wire by itself is grains, and resistance. Resistance is passive and has no PHASE component so it is not “audible”. The grains are PHYSICALLY there, and certainly can be measured. We do not have a final answer on how phonons react to grains. Can we hear the changes in identical designs (same R, L and C) but different copper?

Are better electrical design superior to poor designs that just offer better materials but used poorly? Don’t buy the BOM, Bill Of Materials, buy the DESIGN and the BOM. One and not the other is not going to get you there. The DESIGN influences the results far more than the wire BOM, that I will let you know.

Make sure the comparison is the exact same material and physcal design outside the copper and audition for differences is the best “answer” as ONLY the copper can explain what you hear…it won’t let you know WHY, though. No one can define that interaction yet. Ignore theory if you are told to pay for it, pay for what is known. And, we know fewer grains is more expensive wire to make as it is drawn SLOWER and at LOWER temps than higher grain copper. Time is money. This we know.

Truly better R, L and C and swept Rs designs are still $$$ enough without making things up about how they are working.

I’d concentrate on how the wire WORKS in practice. Can I HEAR a truly better meauring cable in MY system? Is it affordable and realistic relative to what I can truly hear?

Interaction of simple reflectons, not RL as a transmission line, impacts of a given cables impedance with repect to freqency interacts with the amplifiers damping factor and the load (speaker) variation with respect to frequency. Speaker cables have more interaction issues than Interconnects, IC, since an IC cable sees an “infinite” input impedance making that interaction more consistent system to system. One of the three issues is “fixed” in place. That helps. All speakers and amps are different so most, not all, applications see speaker cables making more differences than IC cable. If your speaker is a straight resistive load (some are real close) it’s might be a toss up for what’s best.

True, how wire is physically configured and with what materials is a leading indicator of POSSIBLE application performance but it isn’t the final answer, it just lets you know if you are wasting your time on designs that don’t, “measure up” to be truly better.

Try to determine a true KNOWN from a THEORY in a design. As a customer, you deserve to have the proper information available for consideration.

Galen Gareis