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#160643 - 03/03/07 06:30 PM oxygen free copper
scameron81 Offline

Registered: 02/24/04
Posts: 80
Loc: Healdsburg, ca, USA
Can anyone enlighten me on what the story is behind "oxygen free" speaker cable? It seems like a marketing scam to me.

Study Guides for VDV / Structured Cabling Installers
#160644 - 03/03/07 06:39 PM Re: oxygen free copper
renosteinke Offline
Cat Servant

Registered: 01/22/05
Posts: 5305
Loc: Blue Collar Country
"Oxygen free copper" is a form of copper, nearly pure, that is used for wires. No other form, AFAIK, is used for electrical wires.

It does differ from 'simple' copper; I can attest that it is noticeably harder to machine than other forms of copper.

Also, AFAIK, this level of purity is difficult to achieve in recycling, so wire is made from "virgin" copper ore only.

#160645 - 03/04/07 12:55 AM Re: oxygen free copper
e57 Offline

Registered: 05/27/03
Posts: 2837
Loc: S.F.,CA USA
Unless you are sending a man or a woman to the Moon or Mars I really don't think it matters. Oh wait, unless it is in the job spec's and they are willing to pay too.

Otherwise, for general building wire, or all but sensitive medical equipment - no it doesn't matter.
Mark Heller
"Well - I oughta....." -Jackie Gleason

#160646 - 03/04/07 08:14 AM Re: oxygen free copper
NJwirenut Offline

Registered: 09/15/01
Posts: 816
Loc: Bergen County, NJ
Reno's right. Essentially ALL electrical wire is made from OFHC (Oxygen free, High conductivity) copper. Also called "Alloy 10100". Minimum 99.99% Cu.

The "oxygen free" terminology applied to audio cables is just marketing hype. An ordinary piece of zip cord is made from the same type of copper as the megabuck audio cables are.

#160647 - 03/08/07 02:59 PM Re: oxygen free copper
Scott35 Offline

Broom Pusher and

Registered: 10/19/00
Posts: 2724
Loc: Anaheim, CA. USA
Regarding the Oxygen-Free Copper Conductors used for Audio Equipment…

Does anyone know of any independent studies (as in non-biased type of study), where through a Double-Blind process, the validity of claims towards Oxygen-Free Copper's Sound perception has been proven, or disproved?

What seems peculiar to me is that I haven't noticed too much attention placed on the use of OFHC for Patch Cords - or anything in the "Preamp" or "Line Level" areas; only in the Loudspeaker Connection areas - excluding the use of OFHC for Voice Coils, Leads, Crossover Components, and Terminals.
Seems that these would be the more crucial areas to use the Megabuck Copper.
I may not had noticed any references, probably since the entire issue is $$$ oriented to me, so it becomes unnoticed!

I have heard some Audiophiles claim that OFHC Speaker Wire does make a noticeable difference in the complete sound package.
On the flip side, these same Audiophiles purchase Hubbell 5362 Receptacles for $180.00 each, so describes the Quagmire I am facing!

Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!

#160648 - 03/08/07 03:11 PM Re: oxygen free copper
BuildingHomes Offline

Registered: 11/19/06
Posts: 18
Loc: Burlington, Ontario, CANADA
I recall reading somewhere about what oxygene free really meant (removal of iron or something from the mix)

It may have been at AudioHolics. These guys are sometimes insane with their details.

This guy is also a pretty good read:

#160649 - 03/08/07 03:21 PM Re: oxygen free copper
hbiss Offline

Registered: 12/16/03
Posts: 893
Loc: Hawthorne, NY USA
Does anyone know of any independent studies (as in non-biased type of study), where through a Double-Blind process, the validity of claims towards Oxygen-Free Copper's Sound perception has been proven, or disproved?

Non-biased double blind study? Absolutely. This is done all the time with much of the audiophile snake oil that's out there. Just look at the ads. Seems the results are directly related to whoever sponsors the test however.


#160650 - 03/08/07 04:37 PM Re: oxygen free copper
techie Offline

Registered: 05/17/05
Posts: 240
Loc: palo alto, ca usa
I can't point to any specifics, but I have heard of numerous tests being done by audio professionals, using ears, and test equipment that show that the "oxygen free" speaker cables are in fact snake oil..

The results showed that there was no measurable difference between the "oxygen free" cables, and COTS cable of the same gauge.

I think "oxygen free" refers to the braincells of any person who actually believes the snake oil salesman.

Personally, I'm happy with any appropriately sized cable from Belden, West-Penn, etc..

For portable cabling, SJ/SJO types work just fine. If you're wiring your bookshelf speakers, a roll of zipcord works just fine.

#162623 - 04/22/07 12:46 PM Re: oxygen free copper [Re: techie]
Tesla Offline

Registered: 06/16/04
Posts: 1280
Loc: Sacramento, CA
'Oxygen free' is a necessary condition to draw copper into wire. If it's an electrically conducting copper wire it's by definition ALWAYS oxygen free.

Copper ore is crushed, floated and reduced to crude plates. These are then electrolically replated producing high purity metal. This must be further processed to get rid of the oxygen impurities left in by the plating process. After this the copper is sold as 'WIRE BAR' ie extrudable/drawable copper suitable for conductor usage. Wire bar is a quoted commodity and is the feed stock for Belden et al.

#162728 - 04/24/07 02:32 PM Re: oxygen free copper [Re: Tesla]
Alan Belson Offline

Registered: 03/23/05
Posts: 1801
Loc: Mayenne N. France
Copper is refined electrolytically in a bath of acidulated copper sulphate solution by deposition on a cathode and is easily produced 99.96 to 99.99% pure. American copper contains about 110oz of silver and 1/2oz of gold per ton, which are collected as 'anode slime' with other metals. Other impurities dissolve as sulphates in the electrolyte.
Anode, 'poled' touch-pitch copper, before electrolysis, contains between 0.02% and 0.04% oxygen. This small amount is necessary to strike a balance with cuprous oxide, Cu2O , which renders the melt brittle but is part of the refining process to remove iron as a slag. Electrolysis may reduce oxygen levels further, but the common commercially produced metal, as drawn into wire, is essentially very pure indeed and virtually oxygen free. Yep, it's snake oil.
Wood work but can't!

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