Buying used old cables

Is there a life-expectancy of old cables? Old cables
can oxidize (rust) and get brittle. Thus, lose their
conductivity. I have old Monster speaker cable in my
storage area which shows darkened, discolored wire. Is
it still useful? Mobility, relocating, moving, bending,
manipulating, as well as aging must have negative
consequences on any cable. Should we consider this in
our purchase of "used" cable thinking we are getting a
good deal?
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As Elisabeth said, generally there is no problem with used cables. I'd say that they're generally preferable, since they'll be burned-in and operating at peak effectiveness by the time you put them in the system. (Many new cables need 100-300 hours to start sounding as good as designed).

Occasionally there's a "bad batch" or bad design (like the original Monsters that corroded way up under the covering. They need to be kept dry, but problems are generally visible at or around the terminations. If there's a little corrosion right at the termination this could lead you to a great bargain, where you buy the cable dirt cheap, chop off a few inches and re-terminate. (That's a great way to buy hyperexpensive cables if you can find any flawed like that).

The thing to avoid is cables that have been in a poorly sealed basement and actually have serious corrosion. This is pretty darned rare and can be avoid generally by sticking to highly rated sellers.

Still, bottom-line is that used cables are generally and excellent deal and highly recommended.

Used cables are good I have had some cheaper cables like monster and other discolor and the rubber jacket change for the worse or the little rubber bands around the connectors dry rot and fall off. But all my real cables like kimber, audioquest etc look as of they where new 10 year later.
Living just north of the Golden Gate Bridge for an extreme example of cables. The cables on the bridge are constantly being painted due to the salt air, aside from that they are the same ones up there since 1937. Audio cables are not much different, as long as their sheilding and ends are kept protected whats inside should stay as good as new.
Uru975, so what gauge are the G.G.B. cables? Can I get a pair of 1 meter cables cut from them :-)
Most cables usually get better over time. I have seen maybe the bare wire ends of a cable turn a little dark, but under the cable skin the cable was fine. I have never seen terminated cables deteriorate and I have an old M1000 Monster interconnect that is perhaps 15 years old and it's fine. Copper turns greenish and silver tarnishes, but only iron rusts, don't know of any audio cables made of iron.
My arteries rusted and went to hell since I
ventured past thirty-nine and my tubes went
from twelve gauge to slim threads, just like
my lamp-cord speaker wire I used forty years
ago. I am sure I can't sell them on the 'gon.
Thanks for the feed-back. Bgordon829
Incidently, Cyclonicman, all metals save gold react with
oxygen to react chemically. That may not be called "rust-
ing" but it sure is oxidation. And then there is airbourne
sulfonamides and acids and plain old water and ultraviolet
and infra-red radiations and other x-rays that penetrate
deep into and thru insulations. Then there is that corros-
ive stuff called "electricity" and heat. Nothing is
impervious and inert. Even me. BG
My understanding is that unless there is an airtight seal where the wire goes into the connector, air will slowly get under the dielectric and oxidize the copper. To what degree, I'm not sure.

As far as I know, not many manufacturers address this issue. Not Kimber or Audioquest for sure. Cardas does, as they use Litz wire and have special soldering techniques as they take this seriously.

I have a 6" sample of a Tara Quantum III+ speaker cable with 8 solid core conductors. For years, the bare copper showed no change. Now, it does look like it has oxidized. It is kept in a cardboard box - just kind of a novelty item for me.

If anyone knows more about the aging of cables, please enlighten us. I do know that there are people in this industry who say wire does oxidize and degrade in sonics after some years.

If anyone knows more, I'd be interested.
I hear you BG, luckily I have never had the problem with some of my older cables. However, I am starting to feel the rust creeping in since I passed 39 as well!
I must admit that serving the compulsion to shorten all
interconnects, speaker wire and power cords to the short-
est length, I have replaced male ends on power cords with
hospital-grade connectors while cutting off significant
extra length of wire. That suspends the wire off the rug
as well. I have even soldered new RCA connectors on some
interconnects. Sonics have not suffered noticably. Now
I would not do this to an expensive item that comes with a
swedged-on connector. The orderly snake-pit behind my
equipment sure makes me proud, neatnik that I am. But,
I don't know how equipment mfgs. look on this practice and
I certainly don't know what damage I am encouraging. It
may just be a trade-off, though; short connections for
shorter longevity. BG
I've had the copper strands inside Monster cable turn green after having it for a year or so; probably caused by oxidation.
06-28-08: Bobgates said:
"I've had the copper strands inside Monster cable turn green after having it for a year or so; probably caused by oxidation."

Wow, that's still going on. They had that problem decades ago when they first came out. That's not a good sign.

What metal besides gold can withstand the corrosive
damage of Oxygen? We are at the mercy of a giant
presence that invades and permiates most protective
shields at various but persistent rates.
Conclusion: Used, flexible wire is suspect and should
be looked on with caution and only as a temporary
addition to our systems until we can go with replace-
ments of new wire. Even these should be given a
proposed time of replacement. Maybe we should even
ask for an imprinted date of production stamp so we
can refer to that time and plan ahead for replacement.
The value would diminish as time passed on the used
wire market.
oxidation without representation is tyranny.

cross at the green, not inbetween.
Oh, to be 39 again....

Hell, I'd settle for 49............{:>)
I bought an old pair of 12'single hard wire Audioquest SC.They run from Classe Cam-350s to Thiel CS6s.I have tried a few other SC including AP Oval 9.Nothing has been able to out perform the old cheap straight wire.