Speaker wire lesson.

[Bigdog]

After having a problem with my speakers cutting out I bought some new speaker wire. Rememeber my old wire checked out OK with a cable Doctor and a meter to test the continuity. And the speaker still cut out. I can't explain it, so don't ask.

Anyway, there is a difference in the quality of the speaker wire. This difference is determined by the amount of strands in the wire.

Why does it matter? The sound travels down the line on the outside of the strands, not the inside as you would expect. So the more strands a wire has the more surface area the sound has to travel down. This means more quality sound makes it to the speakers. One more thing, the bigger the wire gauge the better it is too. Especially if you make long speaker runs.

I bought a 250 foot spool of 12 gauge wire with 259 strands. The strands are almost as round as a human hair. This is about as good of a 12 gauge wire that you can buy. As far as strand count.

I used the new wires tonight and I could hear a clear difference in the sound. I'm very happy with the results. I never thought my old wires were in bad shape because I have taken good care of them when wrapping and unwrapping them. I make sure they are not twisted up. With the strands being so small and fragile not taking care of your wires could cause the strands to break. Twisting the wires would cause this to happen very easily.

I can't be sure but maybe since the wires are old they could be somewhat oxidized or slightly corroded under the insulation. The corrosion would be on the outside of the individual strands. Remember that is where the sound travels down the cable on the outside of the strands. So a corroded wire could cause the sound to be degraded.

That brings up the next problem. How often should the speaker wires be replaced? Since you will not be able to tell how much corrosion has occured under the insulation, I don't have a clue as to how often they would need to be replaced. At over a dollar a foot they aren't cheap. My guess would be probably every few years to keep the sound quality on the high side.

Has anyone ever seen any recommendations on how often a speaker wire should be changed?

I just figured if an end went bad you just cut it off and replace it. I never really thought about oxidation and the strand count and stuff. I thought a wire would work forever. I don't think that anymore.

[mnementh]

Oh dear! Oh dear! Oh dear!.

Not this old chestnut about skin effect, yet again.

Bigdog, I've read your posts with great interest and in the main, you DO, in fact, talk sense but this time I'm afraid we're in the same area as Alien Abductees, Conspiracy theorists and people that don't believe we've been on the Moon!!!

As someone who has worked in the Electronics industry for the last 30+ years and most of them in the Microwave area, I can catagorically assure you that at audio frequencies <= 20kHz, skin effect is nearly non existent and that the current DOES, in fact, travel throughout the bulk of the wire.

Might I suggest you have a look here;

http://sound.westhost.com/articles.htm

where you will find many, many genuinely excellent articles, covering lots of audio application and much more importantly, the general debunking of some of the more ludicrous claims about many things, "Audio".

Go down the page and check out the "Truth about cables" articles.

This guy has repeatedly challenged many major cable manufacturers to back up their claims with facts and fifures and NOT ONE SINGLE ONE has come up with the goods.

Trust me on this, that if you can hear a difference in your cables and your old cables were reasonably good, then it's because you wanted to hear the difference, not because there is any. Sorry.

Sandy

[mnementh]

Just another link, this time from an audio nut website;

http://www.audioholics.com/education/ca ... ker-cables

At typical audio frequencies, skin effect will only make about a 3% difference in cable resistance and even this website believes it to be irrelevant in the greater scheme of things.

Sandy

[Moonrider]

Here's another good primer on the basics of speaker cables:

http://procosound.com/downloads/whitepa ... Cables.pdf

One thing I have to ask though . . . were your old cables made by Monster?If so, you may want to check the jacks on the back of the speakers and in the amplifiers. Monster cables have been documented as using an oversize plug that actually spreads out and damages the connector jacks.

[Bigdog]

I still say regardless of the over abundance of opinions that corrsion on the surface of the 200 micro strands of wire could impede the signal traveling down the line.

Given the choice between using a "clean" cable or a corroded one which would you pick?

I also say that after a certain point of corrosion there would be a noticeable sound difference.

Just as my new speakers clearly sound totally different from my old ones in a side-by-side comparison. Same speaker, same company, same design, same model. Just newer. Different sound. The old one has way more bass. Now since they could not be compared to each other brand new, I have no way of knowing if the old ones have degraded over time or they were designed to sound as they do now. People can hear a better, clearer sound with the new ones.

Each speaker wire article is one persons OPINION.

How do I know that "BOB" is or has any better information than "Joe"?

http://www.roger-russell.com/wire/wire.htm

It appears that I have innocently stumbled upon a bigger conspiracy theory than the killing of John F Kennedy and Area 51.

http://en.wikipedia.org/wiki/Speaker_wire

Everyone has an opinion on the subject. Now on who and where do we pick the one that is correct? I would suggest the the truth is somewhere in each of the opinions. One will have to read and decide for themselves.

The theory I presented that I read somewhere else, seems to make sense to me. Is it totally correct? Who can say? Is it totally incorrect?

I still say BIGGER is Better. So big connectors and big wire strand counts sound good to me. The new wires sound better than the old ones. When I started playing I wasn't listening to hear a difference. I never gave it a thought that it would sound different. The difference jumped out at me. I was surprised by the difference. I wasn't expecting it or looking for it.

Let me tell you about my alien abduction story.....

[mnementh]

I still say regardless of the over abundance of opinions that corrsion on the surface of the 200 micro strands of wire could impede the signal traveling down the line.

Given the choice between using a "clean" cable or a corroded one which would you pick?

I also say that after a certain point of corrosion there would be a noticeable sound difference.

Let me tell you about my alien abduction story.....

O.K., lets let logic step up to the mat here.

Lets assume that we are in a particularly corrosive area and that after a period of time the Copper in our hypothetical speaker leads corrode to a certain depth and for the sake of argument and ease of calculation let's let this be 0.001".

If you have 200 strands of Copper at 0.010" diameter each, you have a total cnductive area of 0.0157 square inches. For a 0.001" depth of corrosion, you now have 200 starnds at only 0.008" and a conductive area of 0.0100 square inches, a reduction of 36%

Now lets double the thickness of the wire and go down to 50 strands, for the same conductive area (do the math, it works ) and let's have the same amount of corrosion (0.001"), so that we now have 50 strands at 0.018" to give a conductive area of 0.0127 square inches.

This amounts to a 19.1% reduction due to corrosion, rather than the 36% for the 200 strand wire.

So, in simplistic terms, I'd use 50 strand, rather than 200 if corrosion is likely to be an issue, every time.

I'm just waiting for the first post about "directional" speaker and interconnect cable to pop up, as I really do need a good laugh.

Sandy

[Moonrider]

I still say BIGGER is Better.

That part's on the nose. Lower gauge wires (bigger) offer less resistance. If you've swapped 12 gauge for 16 gauge on a run of over 25 feet, then it's highly likely you hear the results of less resistance and correspondingly better speaker damping. The article I linked to is a "basics" article. If you like I can give you some links to the science and mathematics in depth. No opinion involved.

[Bigdog]

I still say regardless of the over abundance of opinions that corrsion on the surface of the 200 micro strands of wire could impede the signal traveling down the line.

Given the choice between using a "clean" cable or a corroded one which would you pick?

I also say that after a certain point of corrosion there would be a noticeable sound difference.

Let me tell you about my alien abduction story.....

O.K., lets let logic step up to the mat here.

Lets assume that we are in a particularly corrosive area and that after a period of time the Copper in our hypothetical speaker leads corrode to a certain depth and for the sake of argument and ease of calculation let's let this be 0.001".

If you have 200 strands of Copper at 0.010" diameter each, you have a total cnductive area of 0.0157 square inches. For a 0.001" depth of corrosion, you now have 200 starnds at only 0.008" and a conductive area of 0.0100 square inches, a reduction of 36%

Now lets double the thickness of the wire and go down to 50 strands, for the same conductive area (do the math, it works ) and let's have the same amount of corrosion (0.001"), so that we now have 50 strands at 0.018" to give a conductive area of 0.0127 square inches.

This amounts to a 19.1% reduction due to corrosion, rather than the 36% for the 200 strand wire.

So, in simplistic terms, I'd use 50 strand, rather than 200 if corrosion is likely to be an issue, every time.

I'm just waiting for the first post about "directional" speaker and interconnect cable to pop up, as I really do need a good laugh.

Sandy

I'm going to guesstimate my wires are at least 10 years old. So do you think in 10 years there is any corrosion on my wire?

If at the rate you suggested, I could have seen a reduction in sound by anywhere from 19 to 36%. So would I have noticed a sound difference at those rates?

Should I have changed the wires? And if so when should they be changed again. Since we really don't know at which % rate the corrosion occurs. It is likely that after 5 years they could have reached a point of noticeable sound loss. What would it have been at 10 years?

Does anyone agree that they should be changed at some point in time? Due to loss of signal from corrosion? OZONE can and does permiate the insulation. How long would it take? Plus the ends of the wire are left open. I don't believe that the wire is in an air tight insulation. Plus the copper has been exposed to the atmosphere during the manufacturing process. So it had a head start on the corrosion from the day it was made. I highly doubt the wire is made in a vacuum. So it's contaminated.

And does the electrical impulse travel down the outside or the inside of the strand? Inside the corrosion wouldn't matter unless the corrosion went the whole way through the strand. If it travels down the outside of the strand then the slightest bit of corrosion would start to degrade the impluse. If it travels down both the inside and the outside there is still a percentage of degridation of impulse.

So which way is it?

[mnementh]

Hi Bigdog,
As I said previously, it is the Copper that conducts the signal. not the corrosion coating, that is in fact an insulator.

Therefore until the cable degrades to a point where it can't actually handle the current required for the speaker to achieve full volume (and that would be a LOT of corrosion, by the way), there would be no audible difference in the sound.

By this theory, then you were probably correct to change out your cables after 10 years use but really, only you can say if you think it was necessary.

And as for skin effect, as corrosion bites into the cable, the effective diameter of the wire would reduce and the outer circumference would then be subject to skin effect (if we accept that such exists to any noticable level at audio frequencies).

As to your last paragraph, if the corrosion went ALL the way through the wire, then you would no longer have a conductor at all and the connected speaker would be silent.

However, as to the "impulse" you mention, then again skin effect is negligible. Please remember that a Copper wire can, in NO WAY, affect the QUALITY of the signal it carries (Caveat is inductors and very, very long leads, obviously), only the QUANTITY. This would ONLY affect the volume level of the speaker connected to it, NOT the sound QUALITY (whatever criterion you use to define that).

My criterion is that what I put in at one end of a speaker lead should come out at the other end, unaltered. Then if the sound is crap, then the fault is mine, not the cable.

Have look at this URL to demonstrate the idiocy that "audiophiles" go to, in order to "improve" their listening pleasure.

http://www.electronicsweekly.com/blogs/ ... kes-2.html


Basically it should be made a crime to take money from idiots that buy this codswallop.

Sandy

[mnementh]

Does anyone agree that they should be changed at some point in time? Due to loss of signal from corrosion? OZONE can and does permiate the insulation. How long would it take? Plus the ends of the wire are left open. I don't believe that the wire is in an air tight insulation. Plus the copper has been exposed to the atmosphere during the manufacturing process. So it had a head start on the corrosion from the day it was made. I highly doubt the wire is made in a vacuum. So it's contaminated.

Sorry I didn't repond to this point earlier!

As the level of Ozone in the atmosphere is absolutely minute, ~0.00004% by volume, (www.physicalgeography.net/fundamentals/7a.html) I would suggest you would be "Dead buried and very well rotted" for a VERY long time by the time Ozone caused any problem with decently covered lead.

As to the manufacturing process of Copper wire, it is made by extruding the metal through dies which effectively strip any surface coat of Oxide or anything else.

This couple with the fact that Copper os one of the most corrosion resistant metals would suggest that it would take a VERY long time for the wires to deteriorate to a level that would cause problems in cables. Again, however, I refer to wire strands that are NOT so thin that any corrosion would cause conductive failure.

http://en.wikipedia.org/wiki/Erosion_co ... ater_tubes

Quote from the above article
"The corrosion rate of copper in most potable waters is less than 25 µm/year, at this rate a 15 mm tube with a wall thickness of 0.7 mm would last for about 280 years. In some soft waters the general corrosion rate may increase to 125 µm/year, but even at this rate it would take over 50 years to perforate the same tube."

This for Copper in constant contact with saturating water.

My viewpoint is that;
1)skin effect is NOT a remotely viable reason to choose huge numbers of strands for cabling.
2)if there is a likelihood of corrosion where you are working, then LESS strands rather than more would be preferential. (see earlier post)
3)do NOT get hung up with audiophile nut jobs, whose brains are three feet south of their heads and believe there is such a thing as directional cable for an alternating signal.
4)if it sounds O.K., then it probably is. If it ain't broken, don't fix it!!!

For what it's worth, my louspeaker cable of choice is standard 16A mains cable with the Earth and Neutral wired together and the Live for the feed signal.

THIS HAS NEVER LET ME DOWN, EVER!!!

Sandy
P.S. for what it's worth, I also think that buying Oxygen Free Copper Wire (OFCW) is a waste of space. 99.9999999% of Copper wire is already Oxygen free because that's the preferred way of making it, so why buy wire at twice the price, or more, just because it says "Oxygen Free".

[jr2423]

While corrosion is a factor, I don't believe it is as much as broken strands are. As careful as we all may be with our cables during set-up and tear-down, wire strands can't help but become work hardened over a period of time and break. This is where I would expect cable degradation to occur more frequently than corrosion.

I also think this could be a cause for intermittent continuity. Depending on how many strands are broken and where they are broken, this could cause the mere position of the cable to work as a switch. Move the cable a fraction of an inch and it could make or break continuity. I've experienced this with mic cables years ago.


But then this is only my thought, your mileage may vary.