Aw geez my speaker wire has turned green inside the jacket.

Ok, so 6-8 years ago I bought a spool of 12 gauge wire at a box store not to mention any name, but the orange one. What can I say, it was on clearance? It's a shame, as I have the whole theatre room wired up with this (now green) crap. Interestingly enough, it seems worst inside the jacket, little or no issue on the bits at the contact points.

I don't actually have enough wire laying around to replace it all, so I'll be picking up some new stuff soon. Anyone here been through this? And now the dividing question... Will it matter? If the corrosion is on the wire, but not fouling the contact ends, is it likely to degrade the sound? I think I have enough wire to replace the front end, I'll try that tonight to see if it makes a difference.

Unfortunately even the remaining wire on the spool has "gone green" (not in a good way). So I don't have a "control" wire to measure for comparison.

By the way my intention is to replace it with either 16 gauge or a lighter insulated 12-14. This now green crap, was the most heavily insulated, extremely hard to work with stuff I've ever dealt with. It's so heavy and stiff, I've worried about damaging gear with it.
 
As the wire's polyvinyl chloride insulation deteriorates, hydrochloric acid forms. This catalyzes the oxidation of the copper; the green stuff is most likely copper chloride (CuCl2; "cupric chloride" a/k/a copper(II) chloride).
Better wire should have better quality insulation.

In practice, I don't think it does much harm unless the oxidation is really extensive. The 16-ga Radio Shack wire on my Monitor 7As is oxidized where at the interface of the insulated and stripped wire. No audible effect.
 
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No, it does not matter, except perhaps esthetically. Keep contacts clean, use wire of sufficient gauge, and enjoy the music. Life is WAY too short to worry over copper turning green inside insulators. It still passes electrons just fine, since the patina is only on the surface of the wire, and speaker wire only carries electrons; nothing magical.

EDIT: My speaker wire is 16-gauge lamp cord. It's brown, not clear. If the copper is green inside, I'd have no way of knowing. And that's just fine for runs of 25 feet or less.
 
I don't think it will make much if any difference as long as you've got good contact at the ends but, were it me, I'd replace it anyway just because it would bother me to know it.
 
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I beg to differ with those who say a green coating on the wire makes no difference. On a reasonably revealing system, it can make a BIG difference. I picked up some speaker wires that had been coiled, then left to sit for a while in a place where the bottom couple inches of the coil would get wet. Somehow the water penetrated --I assume there were pores or micro-cracks in the outside-- and the wires became green inside, at least over the sections that had been submerged.

They had originally been fairly high-quality cables, but now, because of the oxidation, were in a pile of junk at a flea-market. I bought them for a cheap enough price, and tried them.

They exhibited awful sonic degradation: muddied sound with missing highs, just not good at all. I stripped off the insulation and cleaned them thoroughly and re-covered them, and they sounded fine. I didn't keep them in the end, but they were a good lesson for my ears in just how much green oxidation, even on the outside of a wire, can affect the sound of a signal passing through that wire. Perhaps it relates to the "skin effect", I don't know for certain. What I do know is that I would never want to use oxidized wires again (except perhaps for silver; silver oxide is conductive, unlike copper oxide).

I'd replace those wires.

One way to make sure is simply to replace PART of the wiring, and listen only to those speakers. Try going back-and-forth between the oxidized wire and the new wire, to hear any differences. Don't just listen once; the act of plugging and unplugging wires can remove oxidation from the contacts, and make an improvement that would be unrelated to the effects of the oxidation, so repeat the test (both wires) at least once.

If you cannot afford to replace all the wires at once, start with the main speakers (L-R mains) and then move progressively to the less important ones, as your means allow. Each stage of replacement should make the sound just that much better.

Good luck! :thmbsp:
 
I'm thinking of going the low voltage landscape wire route (more orange box store stuff). At least with the black insulation,( I'll remain blissfully ignorant in the future.)
And for kicks, I might just have my own little crappy wire shootout. Just to see if it makes any difference to my own ears.
 
I have found that the nice install-grade stuff (you know, that gray stuff that is ubiquitous in schools and such), survives well. I have some from the seventies, and it's still nice and golden once I stripped new ends. Been using it for the past couple years and have a bunch left.

I used green speaker wires for a little while, and going to the install-grade stuff made a nice difference in clarity.

Gustuf, if you wanna play with some of the wire I have, you're welcome to it. Not sure how long the lengths I have are, but prolly 10' each.
 
Wow.. shocking!

So many that say the wire has to be pure silver, $500 a foot, and oxygen free to be any good, and here's a room full of people saying oxidized corroded wire won't be a problem... .

I would normally say that silver, copper or what ever wire won't make a difference, so long as the electrons can flow freely in the surface.

In this case, the electrons can't flow freely over the surface with green corrosion on it...

Not to mention, that corrosion can migrate to your binding terminals...

CHANGE IT...
 
Wow.. shocking!

So many that say the wire has to be pure silver, $500 a foot, and oxygen free to be any good, and here's a room full of people saying oxidized corroded wire won't be a problem... .

I would normally say that silver, copper or what ever wire won't make a difference, so long as the electrons can flow freely in the surface.

In this case, the electrons can't flow freely over the surface with green corrosion on it...

Not to mention, that corrosion can migrate to your binding terminals...

CHANGE IT...

Oxidized copper is conductive.
 
I bought the same wire, from the same store, with the same results....turqoise colored wires. 2 years ago I finally noticed these green wires, that were 30 foot runs to my rear speakers. Out of curiosity, I measured the resistance, and was getting 6 ohms on a 30 foot run. Correct me if I'm wrong, but that can't be good. I tried to strip the wire to get better (less oxidized) strands to connect to the speakers, but it was green forever.
 
6 ohms would clearly be a problem.

Again, I'd replace just as a matter of principle, but I have a hard time imagining the resistance would change that much if you were actually using clean contacts at the end even thought it was green for the rest of the length.
 
6 ohms would clearly be a problem.

.

Unless it was 6 ohms when it was originally installed. Still a problem, but not necessarily caused by oxidation.

If the old saying is true that electricity follows the path of least resistance, and the surface of the wire strand becomes too resistive, then it would seem that the path would change to a less resistant surface below the oxidation.
 
I bought the same wire, from the same store, with the same results....turqoise colored wires. 2 years ago I finally noticed these green wires, that were 30 foot runs to my rear speakers. Out of curiosity, I measured the resistance, and was getting 6 ohms on a 30 foot run. Correct me if I'm wrong, but that can't be good. I tried to strip the wire to get better (less oxidized) strands to connect to the speakers, but it was green forever.

6 ohms is definitely a problem. A 30-foot run of 12 AWG copper wire should have a resistance of about 50 milliohms (0.05 ohms) per side according to my wire table. The same length run of 16 AWG should measure about 125 milliohms per side. Any termination resistance associated with the connections to your spade lugs or banana plugs would add to the wire resistance.
 
the skin effect isn't really active at audio frequencies; surface conductivity isn't really too important in audio.
 
Ok, so 6-8 years ago I bought a spool of 12 gauge wire at a box store not to mention any name, but the orange one. What can I say, it was on clearance? It's a shame, as I have the whole theatre room wired up with this (now green) crap. Interestingly enough, it seems worst inside the jacket, little or no issue on the bits at the contact points.

I don't actually have enough wire laying around to replace it all, so I'll be picking up some new stuff soon. Anyone here been through this? And now the dividing question... Will it matter? If the corrosion is on the wire, but not fouling the contact ends, is it likely to degrade the sound? I think I have enough wire to replace the front end, I'll try that tonight to see if it makes a difference.

Unfortunately even the remaining wire on the spool has "gone green" (not in a good way). So I don't have a "control" wire to measure for comparison.

By the way my intention is to replace it with either 16 gauge or a lighter insulated 12-14. This now green crap, was the most heavily insulated, extremely hard to work with stuff I've ever dealt with. It's so heavy and stiff, I've worried about damaging gear with it.

I've seen it happen a bunch of times. Some clear-jacket wire, some black-jacket SJ cable, and some of the orange drop-light type jacket. Audible reduction in audio quality, and never really able to clean the ends enough to be satisfied.

One of the clear-jacket types was Monster cable (only one of the two conductors, the entire length!), and they gave me a free replacement on the 20+ year-old wire.

je
 
If you measure the resistance of the wire, it will be the same.

I can't agree with this... if the wire is corroding, then that means that wire is being eaten up, which means less wire, which means more resistance...

Also, if that wire isn't cleaned and hooked into the terminals, then the connection isn't good, which also means more resistance..

Ya'll just blow me away around here... one second the wire has to be the most perfect wire out there to give you the best sound, then next second cheap corroded zip wire is just fine to keep using..

I mean come on.. it's only zip wire.. the stuff is cheap.. replace it... why even wonder if you could still use it?

BTW, here's a short little paper on wire corrosion, length, and resistance..
http://www.hwhcorp.com/ml40838.pdf

Although it's talking about a circuit with a solinoid on it, it still shows the effects of wire length, and corrosion, and how it can create voltage drops, which in our case with speakers, can and will cause problems with the sound.
 
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I can't agree with this... if the wire is corroding, then that means that wire is being eaten up, which means less wire, which means more resistance...

Copper does not get 'eaten up' when it tarnishes. It oxides into another set of chemical compounds. The Statue of Liberty is not 'eaten up' and it is heavily patina'd.

Also, if that wire isn't cleaned and hooked into the terminals, then the connection isn't good, which also means more resistance..

Yes, the connections must be kept clean. I did mention that earlier in the thread, I think.

Ya'll just blow me away around here... one second the wire has to be the most perfect wire out there to give you the best sound, then next second cheap corroded zip wire is just fine to keep using..

Depends on whom you talk to. I don't have both opinions, only one of 'em. And I don't make war over it; just because I cannot hear a difference doesn't mean I think people who say they can are wrong. If they can, they can. I can't. That's good enough for me. If asked my opinion, that's my opinion.

I mean come on.. it's only zip wire.. the stuff is cheap.. replace it... why even wonder if you could still use it?

We were not asked that. But I believe I did say something like that earlier on, too. If it keeps you up at night, buy new. Otherwise, be happy. Do whatever. I really don't care.

BTW, here's a short little paper on wire corrosion, length, and resistance..
http://www.hwhcorp.com/ml40838.pdf

Although it's talking about a circuit with a solinoid on it, it still shows the effects of wire length, and corrosion, and how it can create voltage drops, which in our case with speakers, can and will cause problems with the sound.

Copper oxidation is primarily simply discoloration (patina) that actually serves to form a protective barrier when exposed to the elements.

Copper is a noble metal; it can corrode, but it is quite unusual. Discoloration isn't it.

http://www.copper.org/resources/properties/protection/underground.html

Seriously; I'm not an engineer or a metallurgist, but copper stranded wire that discolors is simply discolored. If that bothers you, ditch it. If not, be happy. It's not worth a fight over.
 
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