Wire corroding from within?????

[ScottTunes]

I have a spool of speaker wire that is turning green (copper corrosion, I pressume)!

I need to re-wire my 2x12 sealed bass cab (just bought a pair of Beta 12s)...

Is this wire (from year 2003) ok to use?

[seamonkey]

If the insulation isn't brittle, It's fine.
tin the end like you'd do anyhow.
If the solder flux doesn't clean it, just use a little metal cleaner on a rag to clean it before tinning.

[T-Bird]

Hi.

What seamonkey said.

Unfortunately not all the manufacturers use copper grades that are resistant to corrosion.

I do use steel wool or fine emery paper for cleaning before tinning the end.
Yes, I'm cheap as well and don't usually buy pre-tinned wire .

Regards
Sam

[Munjibunga]

You should get wire made of oxygen-free copper.

[ScottTunes]

Originally Posted by seamonkey

If the insulation isn't brittle, It's fine.
tin the end like you'd do anyhow.
If the solder flux doesn't clean it, just use a little metal cleaner on a rag to clean it before tinning.

Originally Posted by T-Bird

Hi.

What seamonkey said.

Unfortunately not all the manufacturers use copper grades that are resistant to corrosion.

I do use steel wool or fine emery paper for cleaning before tinning the end.
Yes, I'm cheap as well and don't usually buy pre-tinned wire .

Regards
Sam

Thanks. Insulation is still flexible... And I have 50ft or so left out of 100... US made, but the clear insulation is turning green...

Originally Posted by Munjibunga

You should get wire made of oxygen-free copper.

I would, but can't afford it anymore... Not even sure if any is available that isn't made in China... And I REFUSE to support China in any way!! Tried to buy an over-priced Neo driver last week... I was told China is no longer selling neodymium to the USA!! And at present, they are the only supplier... That's why I bought the Eminence Beta drivers...

But I digress... Thank you all for your replies! This wire is already in the majority of the cabinets I've "restored," and all of my own cabinets. It seems fine in use... Just wanted to check with the experts here, before committing it to another cab!

Cheers!

[FF Petro]

Originally Posted by Munjibunga

You should get wire made of oxygen-free copper.

That's what I was thinking. I didn't know you could get audio grade wire that wasn't O2 free.

[nashvillebill]

You do realize all electrical copper wire IS oxygen-free, for all intents and purposes? The "oxygen-free" tag comes from audiophile marketing.

So where does the green crud come from? The interaction between the insulation and the copper. (Chlorides and sulphates from the insulation for example) Not oxygen.

When copper oxidizes, it turns brown. (Copper oxide is conductive by the way)

I'd junk wire that has turned green. It's the insulation that is sub-par, not the grade of copper used to make the wire.

[JB696]

Oxygen-free and with silver plated strands. Otherwise all the sparkle will be sucked out of your tone. And you might as well use an old lamp cord.

[Munjibunga]

Originally Posted by nashvillebill

You do realize all electrical copper wire IS oxygen-free, for all intents and purposes? The "oxygen-free" tag comes from audiophile marketing.

So where does the green crud come from? The interaction between the insulation and the copper. (Chlorides and sulphates from the insulation for example) Not oxygen.

When copper oxidizes, it turns brown. (Copper oxide is conductive by the way)

I'd junk wire that has turned green. It's the insulation that is sub-par, not the grade of copper used to make the wire.

Really?

[Munjibunga]

Originally Posted by JB696

Oxygen-free and with silver plated strands. Otherwise all the sparkle will be sucked out of your tone. And you might as well use an old lamp cord.

Yes, this.

[Munjibunga]

Originally Posted by ScottTunes

... And I REFUSE to support China in any way!!

So you're a nudist?

[chadds]

Originally Posted by Munjibunga

So you're a nudist?

That's really funny!!!

[nashvillebill]

Originally Posted by Munjibunga

Really?

Yep, really. I've got an old Philco tube radio, made in 1941. The wire in it is made of good old regular copper, nothing "oxygen free" about it. In fact it's probably less pure than ordinary lamp cord made today. Yet if you cut into a strand of wire, the copper is still...copper. No oxidation from within, no green tarnish.

And copper artifacts have been unearthed that are thousands of years old. No oxidation from within, and the copper refining techniques back then were hardly even up to 1940's refining technologies.

Here's one article discussing how undercured Teflon wire insulation caused release of fluoride inside the wire, corroding the wire underneath. http://www.residues.com/pdfs/foresite_teflon.pdf

PVC insulation is the common clear speaker wire insulation, and it is well known to outgas chlorine if improperly cured or used in certain conditions (like in a vacuum). PVC insulation is no longer allowed on aircraft. Aircraft Electrical Wire Types by Alex Paterson Audioholics measured electrical data of various speaker cables here and the end of the article also notes the PVC outgassing in their samples. Speaker Cable Face Off 1 — Reviews and News from Audioholics

[JB696]

I've got a plastic nut on my bass, a low mass bridge, Chinese tubes, and now I find out that my cables may be outgassing. What next? I'll find out that smearing chicken grease on your flat wound strings causes genital warts?

[nashvillebill]

Well, I don't lose any sleep at night worrying about my speaker wire. Though sometimes when I fly on older airplanes...hmmm...

My experience has been that the clear speaker wire is most susceptible to this, but not all clear wire seems to suffer. And curiously price does not necessarily indicate whether or not the wire inside will turn green after a few years, even some relatively expensive wire has while some of my ultra cheap stuff hasn't (and vice versa). I suspect it's a function of how well the PVC was cured when the wire was manufactured.

Some of the older black rubbbery stuff also has crud inside, but I think that's breakdown products of the rubber itself and not corrosion of the wire. Note that the old Philco radio I mentioned earlier had some rubber coated wire inside and by now all of the rubber has turned brittle and broken off...fun...

FWIW, for long-run speaker wires (say for the PA) I use two-conductor 12 gauge SO or SJO power cable. Tough stuff and sounds fine, but then again I'm just a "wire is wire" guy, I don't subscribe to magical wire snake oil theories. But if somebody else believes in pixie-dust-coated stuff made by Peruvian virgins in the dark of the moon, more power to them.

[Rick Auricchio]

Originally Posted by nashvillebill

My experience has been that the clear speaker wire is most susceptible to this...

It might be happening with opaque insulation, but you can't see it.

Clear insulation might also be PVC (Polyvinyl Chloride), which I assume outgasses chlorine. That'll corrode most anything.

[Munjibunga]

Originally Posted by nashvillebill

Yep, really. I've got an old Philco tube radio, made in 1941. The wire in it is made of good old regular copper, nothing "oxygen free" about it. In fact it's probably less pure than ordinary lamp cord made today. Yet if you cut into a strand of wire, the copper is still...copper. No oxidation from within, no green tarnish.

And copper artifacts have been unearthed that are thousands of years old. No oxidation from within, and the copper refining techniques back then were hardly even up to 1940's refining technologies.

Here's one article discussing how undercured Teflon wire insulation caused release of fluoride inside the wire, corroding the wire underneath. http://www.residues.com/pdfs/foresite_teflon.pdf

PVC insulation is the common clear speaker wire insulation, and it is well known to outgas chlorine if improperly cured or used in certain conditions (like in a vacuum). PVC insulation is no longer allowed on aircraft. Aircraft Electrical Wire Types by Alex Paterson Audioholics measured electrical data of various speaker cables here and the end of the article also notes the PVC outgassing in their samples. Speaker Cable Face Off 1 — Reviews and News from Audioholics

Get out.

[nashvillebill]

Why should I get out, aren't engineers allowed to post technically correct facts here? Or is only misinformation allowed?

[chadds]

Originally Posted by nashvillebill

Why should I get out, aren't engineers allowed to post technically correct facts here? Or is only misinformation allowed?

"Get Out" means, " you don't say, I'll be darned, amazing" etc. Elaine Bennis said it constantly. "Get out".

[nashvillebill]

Guess I'm not used to hearing that, since I'm an old fart...No problem then, it's too easy to mis-interpret something on an Internet forum, my aplologies if I misunderstood.

Peace!!!