Do cables age or become too old at any point?

I'v had my big rig all copper speaker cables 6 years, and another pair 8 years, and as far as I know they sound as good (or better) as when well broken in. And I used a 25 year old length of 6 ga stranded copper as a mainline for a dedicated system, and it sounds great. It was previously used as wire for an ARC welder which used huge amounts of current when actually welding-- just helped to break it in I think;>) Personally, I think as long as end points/contacts are kept clean, copper will last a LONG time. Cheers. Craig

All copper oxidizes with age. This is pretty easy to tell though, as if it is still relatively shiny, it's still "fresh". When it is getting darker and loses brilliance, it is time to either replace or reterminate. Sean
>

The copper inside a cable's jacket is not expose to air and therefore cannot oxidize. It should be fine for a very long time. When you buy cable it does not need a "freshness date".

Only if you are using bare wire, the exposed ends as Garfish mentions can oxidize. The ends can be tinned with silver solder to stop the oxidation. Silver will oxidize, but is still a good conductor. Those ends can always be re-done every few years. You'll only lose an inch of cable each time.

If the cabes have copper spades connections, etc, they can be cleaned (as per Garfish).