I got a pair of original Monster speaker wires from around 1985...they have turned green, but I have the ends tinned with solder, are we saying that these wires are no longer 12 guage or whatever guage they were originally? Should they be tossed?

oxided copper is not as good of a conductor as regular copper, it may even drop down to a semi-conductor. that is why people use gold plating a lot on ics, etc. having said that i dont know how much that oxidation affects the sound. its nice to get some speaker cables that are pre-terminated so that they should never oxidize on you. i use bare wire on my speakers (at the moment) and just trim off the ends every year or so to expose some fresh copper, eventually ill get some different speaker cables where i wont have to worry about oxidation though.

Tinning the exposed copper end of a speaker wire with solder will keep it from oxidizing - just remove the rosin residue from the soldering process with alcohol before using the wire. Also, most of the speaker wire I buy has tin plated strands which will never oxidize.

Hi All,

As a EE, I just couldn’t resist commenting on this thread.

Copper oxidation is an obvious (and observable) phenomenon with non-plated copper wire.

But it’s possible effects, in any area other than connection interfaces, would have to be extremely limited.

1 The oxidation layer would be rather thin. Unless you want to overplay the possible interactions with (RF) skin effects, it’s effects on the overall transmission efficiency (resistance) of a cable would have to be (IMO) almost nonexistent.

I am not talking about hazardous (vaporous) environments, this is another discussion altogether. (UL Salt Spray Test anyone?)

2 At the connection points, however copper oxide is an issue that is dealt with by gold (and other metals) plating/tinning. This is especially true in “dry circuit” applications as current flow over a few milliamps (or perhaps microamps) will also keep contact point oxidation at bay.

I have observed RF coaxial cables that have been in outdoor environments for many years and they continue to function just fine as long as the connectors are properly maintained.

Changes (hardening & cracking) of PVC insulation due to UV/ozone exposure may cause a cable to fail in time.

With coaxial cables, there can be small, long term changes in the dielectric characteristics, (characteristic impedance and velocity factor) and perhaps this could, potentially cause some “observable” changes.

Regards,

Scott

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The definition of an expert is a washed up drip under pressure

[This message has been edited by SPasse (edited April 01, 2004).]

Cables, like most people, will go bad if tempted towards the dark side. I say, watch your cables like a hawk!

Jay

thinking of cables all the time tempts me to the dark side. well im usually there all the time anyway.....