Conductor metalurgy and sound.

Now to state the obvious Copper is normally the material of choice, but a close inspection of say a standard Ic it will be clear that a ner of different metals are in the signal path.

So here's the question what effect does the use of different metals have, in the percieved sound ?

We all I hope know that aluminium* is the best condutor followed by silver then copper and so on.

* Aluminium oxide is a poor/non-conductor and therefore inhibits the use of this metal, unless special precautions are taken.

So does the purity of which ever metal used, become more important than the type of metal ?

Has anyone listened to different metal conductors, or are we all basing our ideas on conductivety tables ?

I've used copper, silver platted copper, pure silver, spccs [silver plated copper covered steel], aluminium , nickel, in IC conductors.
Finding that you can get very good sounds from what are supposed to be "bad " conductors.

comments, anecdotes, input and ideas please !

 

Aluminium a better conductor that Silver? Where on earth did you get that information from?

See here:

http://hyperphysics.phy-astr.gsu.edu/hbase/Tables/rstiv.html#c1

As you can see the conductivity of Aluminium is only 3.77 compared with Copper at 5.95 and Silver at 6.29 (all x10^-7 /Ohm M).

As for different materials.... from a conductivity point of view.. the material is irrelivant as long as the cross section is big enough and the length short enough. Conductivity isn't really a measurement in itself anyway.. it's just the inverse of resistivity. If you took an Aluminium wire and made it twice the cross-sectional area of a Silver one of the same length.. it would have a lower resistance than the Silver wire and so from the point of view of pure resistance would be the better wire to use.

The use of brass etc in plugs in itself isn't a problem.. the problem is the relative dimensions of the plugs.

Btw - the idea that plugs etc act as some kind of "restriction" of the signal flow comes from the water pipe analogy of electrical signals.. It's a misleading analogy however .. in the sense that the conductivity of the material isn't the restriction to the flow.. the resistance is... any material that you choose to use for your plugs will add resistance to the cable. If the cables conductor had a resistivty 10.. then that doesn't mean that a plug material of less than 10 is not restricting the signal flow. The only important factor in signal flow is the overall resistance of the entire cable.. the way the resistance varies with materials throughout the cable is not relevant past it's addition of total resistance to the cable. A cable made of a ten ohm lead conductor with a 1 ohm silver plug is identical to one with a 1 ohm silver conductor with a 10 ohm plug..they both have a total resistance of 11 ohms and so will pass exactly the same amount of signal as each other. Exactly the same would be true if the over all reactance of the two cables was identical at all frequencies.. the materials used would be irrelevant.

Of course there are other physical properties to a cable which can be measured.. but the debate is still raging as to whether they are audiably significant or not.

GTM



GTM

 

Interesting thread this, being close to my chosen field, many of the bests cables use a mixture of conductors, dielectric's, ranging from Gold/Silver/Brass/Copper/Nickel/Carbon Fibre, Aluminium /PTFE/Pvc/Foam etc , however are they my just be more than finding the right mix, correct plugs? and do you think that 'One size fits all me dear ' maybe the source components require a differerent 'Type' of suppiled power, ever wondered, why power chord 'X' seems to give a better result with power amps, than say pre-amps or CDP/Dac's than Chord 'Y', worth a thought or 2. WM

 

You are absolutely correct.

I can't locate and surporting evidence and conseed the point
I only wish I could find my chemical data book, that gave the reasoning. The data book provided the information in the common order as you illistrated but indicated, as an aside that without the oxide coat it would be a better conductor.

But that was not the point of the post.

What effect on the percieved sound do different metals have?


quick observations

Cu Full and rounded soft[?]
Ag/Cu bright hard detailed forward
Ag Deep, smooth and very detailed
spccs detailed but lacking bottom end
Ni Hard edgey
Al Hard but detailed
Ag [still to try]
C [still to try monofilament]


I'd rather have your opinions and idea's rather than spelling correction, please!

 

Hi

There are a number of factors with cables. The main thing is that we are looking at AC & that has a load of factors to consider.

As well as the different conductors you have to look at the various designs (eg. twisted, coaxial, spaced conductors). Values of inductance & capacitance are of a big concern. Along with resistance these will shape the potential bandwidth of the cable.

Most cables will have a bandwidth in excess of the audible range but there may be effects in this range due to out of band effects.

Also there is the ability of the source to drive the cable in question. How does the cable load react with the source or load. The cd to pre amp, pre amp to power amp, power amp to speakers. The various electrical properties could alter the response.

The purity & structure may have a bearing on the sound.

There is also the effect of the various insulators on the cables.

It would be interesting to do experiments on the different type of metal. For example DCT treatment seems to be an area worth looking into.

What you need to do is to make some cables that are identical except for the metal.

That would be interesting.


I must admit when I saw the post about Aluminium being the best conductor I nearly fell off my chair.

SCIDB

 

Now that's an idea.....well actually I thought about this a couple of years back.....

That was where the evolution of the "Zero cost" cable came from. I've been able to test some of the metals with this design philosophy.

Copper.... easy get a roll from maplin
Silver.... Yep done that now and bloody good it is
Spccs..... split the coax for the centre cores
Ag/Cu..... strand though rather than solid core
Au ..... Cost factor not yet tried.
Al ..... The only Al wire I have is rather thick
Cr ..... Twinned with the above [thermocouple?]
Ni ..... Split a mains cable...yes a three core blue yellow brown screened ptfe using Ni ? Very strange, not tried it yet

So I have the materials, but some of them have dissimilar constructions.

Zero cost cable.....for those who don't know it

former arround which two or more cores are wound, either crossing themselves or running parallel.
One as signal or hot and the other as ground or return. If a third is used it may be connected at either end or just at the source end, to produce a Pseudo balanced effect. This may also be screened with the use of copper adhesive foil and ground at the source end. Plugs best you can get/afford!

 

Personally.. I'm totaly unconvinced about different metals having differing sound "characteristics".. At least in the case of simple pure conductors.. not plated etc.. of the same type.. (eg monocrystal etc). As long as the crystaline structure of the two metals is the same the only difference between two metal conductors will be the amount of "free" electrons in the "conduction" band. The smallest electrical signal that can be transfered by any conductor.. is one that is equivilent to the charge on an electron. As long as there is enough free electrons to convey such a low level signal. The two metals will have exactly the same "resolution", (ie both will be limited by the lower limit of charge transfer - one electron). The only effect the differing metals will have on whether or not there will be free electrons to cary such a signal is their resistivity. This determines whether there will be such a free electron to carry the signal in any given unit cross section of the conductor. Silver has approximately 6% more such free electrons than Copper.. and so for the same unit cross-sectional area.. will have more free charge carriers for any given signal level that it is passing.

It could be argued that this means if copper has 100 electrons available to pass a current.. and silver has 106.. then if you pass a signal which requires 100 electrons to carry it.. then attempt to pass a signal of a level which would require 3 electrons.. a copper conducter will not be able to transfer that low level signal.. but the silver will.. hence the supposed higher "resolution" of silver. This is true to a point, BUT.. all that is needed to overcome this "restriction" is to provide more copper. (ie greater cross-sectional area of = more available charge carriers). Given that every electrical circuit will have a maximum current requirement given the load and supply voltage.. it's not exactly hard to determine just how much of any given conductor will provide an excess of charge carriers..ensuring that every level of signal will be transfered.

As SCIDB has stated.. there are other factors which are probably more relevant.. such as grain boundries and the barrier they present to charge transfer, dialectric absorbtion losses.. which litterally draw power and so some of the precious signal from the conductor, cable geometry.. etc etc.

GTM

 

Which is precisely why the question is asked.

Diffeerent topologies undobutedly play a significant roll. But if the wire are kept to a single twisted pair, using the same gauge,insulation and plugs, As I have done Why the significant difference in sound. I believe you are quite correct in what you have said, but say I substituted gold wire or nickel, what effects would that achieve ?

You are almost saying that there is such a small difference between copper and silver [ 6 electrons] that the relative sonics should be much the same. [Please correct me if that not what you are saying !]

Whats the current theory for current flow ?

are we doing the newtonian balls now or the elctron wave, or the one in one out or others ?.

From the reseach I've done so far has shown the differences are more than just small sonic traits.

There are very large variation, when the only change is the conductor type.

Please discuss !

 

It's a big area, one we've been delving into for some time, and all I can say is, be prepared to 'Re-equate' some imovable therories, but the smile on your face when you 'get there' is worth a million dollars

 

I'm looking to try 24cr 0.5 gold wire at some stage.

I've a feeling that it could be a rather intresting comparison.

I think it can't be totally bad as there is often quite a bit knocking around in varrious components and curcuit boards. The damn stuff coats many a plug ! and if it sounds horrid I make some jewlery out of the rest.