AudioNervosa
Electro Stimulation Ward => Signals and Noise => Power Cables => Topic started by: Werd on January 14, 2015, 09:05:55 AM
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Why do manufactures of PCs terminations plate their prongs using gold or rhodium? Gold tarnishes bad, it needs the same kind of maintenance as does bare copper. I suppose its rust issues vs the lazy audio hobbyist. Or they are trying to conceal the aluminum underneath. Which is very often the case.
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If gold tarnishes, it is because of whatever other metals were added in to make the alloy. Generally speaking, 14k to 24k gold does not tarnish.
I imagine it's not practical to plate with 24k, but I wonder if it is possible to use 14k gold.
Does anyone know what grade (k) gold plating is used in a typical audiophile situation?
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If gold tarnishes, it is because of whatever other metals were added in to make the alloy. Generally speaking, 14k to 24k gold does not tarnish.
I imagine it's not practical to plate with 24k, but I wonder if it is possible to use 14k gold.
Does anyone know what grade (k) gold plating is used in a typical audiophile situation?
I just looked on the WBT web site and every one of their connectors that is gold plated describes the plating as a single layer of 24K gold. Cardas just says gold plated and does not specify what grade of gold.
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Gold never tarnishes in normal use. That's the only benefit of gold plating (in electronics.)
Gold plating is almost pure gold. Semiconductor leads are pure gold, PCB plate is sometimes pure gold, but that is soft. So for contacts that need more durability they add a little nickel and cobalt, only 0.3%, to increase the hardness. Nickel is resistant to corrosion, so it doesn't affect tarnishing in any appreciable amount.
More: https://en.wikipedia.org/wiki/Gold_plating
Gold is not happy in solder. It reacts with tin to make a contaminant that reduces conductivity and mechanical strength. A tin plated copper lead is a better choice. Then spray with conformal coating if corrosion is a concern. Gold is a relatively poor conductor, so rhodium is used instead when budget allows. Silver is the best conductor of all, but requires regular cleaning.
Edit: Rhodium is worse conductor than gold, I don't know why it is used on audio connectors?
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Ok I get it now, so copper would be better than gold plated if you look after it then? Even with the 24carrot stuff?
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My (mis?)understanding of this topic is that gold plating over pure copper is best (or one of the best).
Of course, I'm not sure if I've ever knowingly experienced gold or rhodium plating....
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Nifty metal plating tid-bits from: https://en.wikipedia.org/wiki/Plating
"With direct gold-on-copper plating, the copper atoms have the tendency to diffuse through the gold layer, causing tarnishing of its surface and formation of an oxide/sulfide layer. Therefore, a layer of a suitable barrier metal, usually nickel, has to be deposited on the copper substrate, forming a copper-nickel-gold sandwich."
I was thinking silver could be the barrier metal, then I read this
"Care should be used for parts exposed to high humidity environments. When the silver layer is porous or contains cracks, the underlying copper undergoes rapid galvanic corrosion, flaking off the plating and exposing the copper itself; a process known as red plague."
Maybe gold can prevent the red plague?
"Rhodium plating is occasionally used on white gold, silver or copper and its alloys. A barrier layer of nickel is usually deposited on silver first, though in this case it is not to prevent migration of silver through rhodium, but to prevent contamination of the rhodium bath with silver and copper, which slightly dissolve in the sulfuric acid usually present in the bath composition.[4]"
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Makes you wonder if all the mismatch in metals is audible?
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Makes you wonder if all the mismatch in metals is audible?
Absolutely audible. We compared several power cords with plugs made of all copper, gold over copper, Rhodium over copper, Rhodium over silver, silver, Copper/silver/gold mix.
All cords were plugged into a brass receptacle first then an all copper receptacle.
Differences were heard. After listening to the all copper first as a standard then all silver as the other standard we found that the plating has a sonic signature. Rhodium being bright, Gold warm and no plating neutral. Silver was just more detailed and a bit leaner.
The biggest difference had was the all copper plug and all copper receptacle. The brass receptacle is a Pass &Seymour 5263A heavy duty industrial grade with cryo treatment. The other made by Voodoo Audio [$60] s a all copper and cryo treated as well.
Overall the plugs using the same material as the receptacle sounded best to us.
Plating will offer a different flavor so to speak than not plated every time.
charles
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Makes you wonder if all the mismatch in metals is audible?
ABSOLUTELY!!!
For those wondering, here's the Electrical Conductivity order in terms of Gold (assuming Gold to be 100%)..
Conductivity
S/m*10^6 in % of gold
1 Silver (Ag) 62.89 147.80%
2 Copper (Cu) 59.77 140.47%
3 Gold (Au) 42.55 100.00%
4 Aluminium (Al) 37.66 88.51%
5 Brass, 10% Zn (CuZn10) 35.86 84.28%
6 Rhodium (Rh) 22.17 52.10%
7 Zinc (Zn) 16.90 39.72%
8 Brass, 40% Zn (standard) 14.94 35.12%
9 Nickel (Ni) 14.60 34.31%
10 Phophorus-Bronze (CuSn4) 12.00 28.20%
11 Iron (Fe) 10.29 24.18%
12 Tin (Sn) 9.09 21.36%
13 Phosphorus-Bronze (CuSn8) 7.50 17.63%
As you can see, silver & copper rules as the best electrical conductors. Gold is not bad but rhodium is poor...
richidoo - you should try soldering direct to rhodium, talk about a super real PITA!!!
My $0.02,
Pete
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I just ordered some base model Neutrik XLR plugs with bronze contacts. :duh Because they were cheap. I did hem and hawed whether to get the brass pins, but I thought it was too much for this project. I bet somebody makes high end XLRs?
I've been reading about pure silver cables and connectors. I'm looking forward to trying that. That's one of the reasons I'm going to active amps - to make very short SCs! :D
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So according to the table, Cardas connectors really are just jewelry, and the smart audiophile wants either a copper base with just gold or silver plating (no nickel), or pure silver.
Going further, I'm thinking a screw / compression connection to the connector would be superior to solder, since you really can't avoid getting low conductivity solder between the wire and the "cup".
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I don't think you can draw that conclusion. The table that Pete put up simply shows the electrical conductivity of the various metal in response to a specific question.
In theory a difference in pure conductivity should not make a sonic difference as it is linear across all frequencies and would therefor affect all of the signal in the same way (although I suppose the even a linear lowering of the signal amplitude could end up obscuring small details.)
However we as audiophiles know that nothing is ever as simple as the pure theory would lead us to believe as there are always other factors in play.
This is kind os a long winded way of saying that each type of metal and plating can have a different sound to it and therefor none can really be called the "best" overall. Each one can have an advantage on matching different combinations of components in different systems. No component or system is perfect, so different materials will help (or hurt) in different situations.
As always, synergy, synergy, synergy.
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I just ordered some base model Neutrik XLR plugs with bronze contacts. :duh Because they were cheap. I did hem and hawed whether to get the brass pins, but I thought it was too much for this project. I bet somebody makes high end XLRs?
I've been reading about pure silver cables and connectors. I'm looking forward to trying that. That's one of the reasons I'm going to active amps - to make very short SCs! :D
Don't want to hi jack my own thread ...should I? What the hell? steve N
States here longer speaker cables are better using shorter ICs than Vica
Versa.
http://www.empiricalaudio.com/computer-audio/audio-faqs/short-versus-long-cables
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Good to see you bobrex!
That is an interesting article, Werd... thanks for posting it here.
According to Steve N, my short cable distances makes IC OK, as long as capacitance is low with quality wires. The price difference of ICs vs SCs will decide it for most people. Especially if wires are silver. :shock:
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So according to the table, Cardas connectors really are just jewelry, and the smart audiophile wants either a copper base with just gold or silver plating (no nickel), or pure silver.
Going further, I'm thinking a screw / compression connection to the connector would be superior to solder, since you really can't avoid getting low conductivity solder between the wire and the "cup".
For speaker cables the Cardas copper spade is the real deal. Especially if connected using cold fusion not solder.
A mechanical connection if properly executed is desireable.
charles
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I don't think you can draw that conclusion. The table that Pete put up simply shows the electrical conductivity of the various metal in response to a specific question.
In theory a difference in pure conductivity should not make a sonic difference as it is linear across all frequencies and would therefor affect all of the signal in the same way (although I suppose the even a linear lowering of the signal amplitude could end up obscuring small details.)
However we as audiophiles know that nothing is ever as simple as the pure theory would lead us to believe as there are always other factors in play.
This is kind os a long winded way of saying that each type of metal and plating can have a different sound to it and therefor none can really be called the "best" overall. Each one can have an advantage on matching different combinations of components in different systems. No component or system is perfect, so different materials will help (or hurt) in different situations.
As always, synergy, synergy, synergy.
It makes me wonder, how much of what we hear (as far as cables) is the sound of the metal vs the sound of mismatching various metals, Including the plating?
Basically the whole supply runs on heavily shielded aluminum into your fuse box (pretty sure anyways?) Then we have solid core copper to the outlet. The outlet could be aluminum or copper - plated somehow. From the outlet to system it varies (obviousily)
It almost makes me wonder if running aluminum right through might clear up any discourse. So it asks the question how far back is audibility of wiring material go. Would our systems sound different if we used copper from the transformer into one's house? IDK but i am inclined to say yes. To me it seems silly that PCs can effect sound and then stop at that and not look at wiring right from the Power generator plant.
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They used a lot of Al wiring in residential homes on LI in the fifties and sixties but went back to Cu because the Al wiring was causing too many electrical fires. :shock:
No improvement to the sound of your system is worth burnish your house down..... at least IMO, although I'm sure there is somebody out there who would disagree with me. :duh