Originally Posted by mirkolop
I have very old speaker wires. There is some green discoloration in one of them.
If the wires didn't get green until you had them for a long time, I'd replace them immediately because they must be slow wires. Some of the wire I've had turn green did so quite quickly, which indicates that they give "fast bass". ;-)
Seriously, the green color is probably due to a very thin layer of copper sulfate or other copper compound forming on the surface of the wire. Sulfur r comes from either the atmosphere or from the insulation. If it happens along the length of the wire, then the insulation is the most probable source. If it happens only at the ends, then the atmosphere is the most probable source.
Other than making the wire hard to solder and very much in need of cleaning at the ends before you reconnect them to equipment, it has no electrical effects.
It is clear and I can see the green going a ways. what is it?
Basically its corrosion. In a few hundred years it might have some effect on how the wire conducts signals.
Should I think of replacing? It is thick wire, I think 10 gauge, maybe 12. Thicker than lamp cord. The only problem is that they run through a built in cabinet. They may be a PIA to replace. If my speakers still sound good, should I worry about it?
The only reason I can think for replacing this wire is aesthetics. If you foresee a visit by the wire police, then you may want to change them out. The corrosion might be very detrimental to bragging rights.