Cable Technology


Oxygen-free copper is a type of copper that has had much of its oxygen content removed to improve its conductivity.

Any copper that had its oxygen levels lowered to anything below 0.001% is considered oxygen-free. There are two types:
oxygen-free electronic and oxygen-free. Standard copper is named electrolytic-tough-pitch and has an oxygen content of 0.02 to 0.04%.
Oxygen-free electronic is classified as having 0.0005% oxygen content and was forged in an oxygen-free environment.
Oxygen-free is classified as having 0.001% oxygen content, and its conductivity rating is slightly lower than oxygen-free electronic.

Oxygen-free copper has a different forging process than pure copper. All copper has oxygen added through the forging process,
but oxygen-free adds less and is smelted differently.During that different process, hot metal is cast into a crucible,
and the bottom part is left to cool while the top remains hot. The entire crucible is cooled gradually, which allows for the oxygen content to be lower.



UP-OCC stands for Ultra-Pure, Ohno Continuous Casting.


The UP-OCC process for refining copper was developed and patented by Professor Ohno of the Chiba Institute of Technology in Japan.

The license to use this manufacturing process is incredibly popular for the production of wire and cable products for the audio/video industry.


In conventional processing, hot molten copper is poured into a cooled mold for extrusion, resulting in multiple, fractionated crystal structure.


While the copper may be "pure" in the sense of measuring gas impurities in the copper in comparison to standard copper refining techniques,

Oxygen-Free Copper (OFC) has undesirable effects that lead many to use more expensive materials such as silver for their conductive strands.


As developed for A/V cable use, the OCC process utilizes a heated mold for casting and extruding, with cooling taking place in a separate process,

the result is a larger crystal size and increased purity that approaches the 6N, 99.9998%!


Looking at it another way, traditional copper has oxygen impurities of 200 to 500 parts per million (PPM), while traditional OFC copper reduces that
to less than 10 PPM. With the OCC process, the figure is cut in half to less than 5 PPM of oxygen,
and less than 0.25 PPM of hydrogen (compared to 0.5 PPM for OFC).


With these results, the OCC process creates "ultra-pure" copper.


The unidirectional UP-OCC has no electric resistance and practically no crystal boundaries.

Accordingly, it is able to transmit electrical signals faster, and with less distortion than ordinary OFC and silver wires.

All of these features make the pure OCC copper and silver the state-of-the art conductor materials for the audiophile cable industry.


• A true unidirectional copper crystal that is as free from impurities as possible to prevent corrosion

• Flexibility and fatigue resistance without impairing conductive characteristics

• Low electrical resistance

• Rapid signal transmission

• Corrosive-resistant

• Non-crystal boundaries

The official SGS test lab that measures wire purity can only test purity up to 6N. Still, today, in 2020, high-end cable companies like Arcolink Japan and Neotech have passed 6N and
reached the 7N 
mark with their audio products, and even surpassed it when testing their cables' purity in their facilities.

This fact discourages some companies which are determinate to deny these latest achievements as hard as they can, so they won't need to start things from scratch with the
development and production of new customized OCC silver and copper wire that are based on the lasest technology. 

Continuous casting of single crystal ingots by the O.C.C.(R) process

A. Ohno - The Metallurgical Soc. of AIME - 1985