Hello guys, i have just got a new pair of chord epic X with their ohmic silver banana plugs. Chords marketing materials claim that the silver sulfide formed when silver tarnishes is still very conductive and can easily be removed by replugging speaker plugs.
However I would like to know with numbers how conductive silver sulfide is compared to gold. there doesnt seem to be information on this online.
I would appreciate if anyone can share their own comparisons with silver and whether the tarnish affects sound?
Gold and rhodium are both worse conductors than silver, so in effect they are âholdingâ back something in the electrical path. The benefit of gold and rhodium is that they donât tarnish and so theyâre used extensively on many higher-end electrical products around the world. Regarding their effect on sound in the hifi/av world, that depends on each manufacturer. Naim have spent decades refining their sound not based on gold in the path and so adding something like this can adversely affect the sound.
With av gear like LG, Panasonic, etc they havenât refined the sound with any subtlety and I find silver on contacts and cables to be extremely beneficial. Silver with Naim gear is good in some parts, but overall ruins the sound. As does gold and rhodium (unless Naim have used it in the original production).
Silver does tarnish over a period of years, but it doesnât affect the signal. Iâve had silver connectors that are 8 years old and with close examination, barely a hint of colouration. A quick pull out and insert cleans the contact anyway.
Iâm pretty sure people hear benefits of gold in their system, but I think itâs masking a problem elsewhere. Once you start adding different metals to Naim, you go down a spiralling losing path ime.
Iâve used silver in DIN pins and power plugs for years and have not seen any (none) affected by sulphide tarnishing to be concerned about.
Pluging out/in cleans them all, DIN pins especially as they have knife edge contacts.
That said, I agree all the posts above, but would add I would think about contacts with dissimilar metals as this has the potential to start electrolytic corrosion and IME, once started, its next to impossible to stop.
Naim amps banana sockets are nickle so I would advise always use the supplied banana plugs or spec nickle.
Ditto speaker end, these banana sockets vary with all sorts of metals, but the same rec, spec the banana pins to be the same metal.
Silver is a better conductor than gold, however for the thickness involved with silver plating versus gold plating, the difference really is absolutely trivial. Silver is a more reactive metal than gold, and as you have recognised it reacts with sulphur in the air. Silver sulphide has a higher resistivity than silver or gold metal, but whether the resistance if the tarnush layer is significant is directly dependant upon its thickness, and without looking into it I donât know the sort if thickness that might develoo in practical situations. Also I donât know whether or to what extent silver can still develop the sulphide coating where it is in tight and direct contact with the metal mating surface - this is unpredictable because it would depend on the absolute smoothness of both touching metals, and their exact alignment in shape, and possibly distance from the edge of the contacting services, and of course the level of sulphur compounds in and humidity of the air
I think of greater importance is that mating metals are best identical where possible, thereby completely obviating galvanic corrosion, particularly in humid environments. Whilst I seem to recall Naim preferred nickel saying it sounded best, my personal preference is for both plug and socket to be gold plate over copper, eliminating both galvanic corrosion and tarnish effects, giving a stable permanent contact for as long as needed . (Of course for lowest resistance it should be guild plate over silver with silver wires connecting.)
If you Google atmospheric sulphur I think youâll find a wealth of information. Far better in terms of anthropogenically caused than in the century following the industrial revolution, it is still higher in cities than many rural areas, and can vary a lot locally.
This vexed me, too. I went for the same metal as on my speaker studs: gold. Then, after researching why silver connectors are more expensive than gold from the same manufacturer, I realised I should have gone with silver.
Since I had already purchased gold connectors, I have lived with them and still enjoy my music.
It is a tug of war in my mind, the same metals (Gold) or silver. At the end of the day, it is either a gold spade on copper wire or a silver spade on copper wire. I went for gold on copper, though I wonder how many microns of either metal is actually involved?
I prefer a spade connector under my speaker stud heads to a twisted copper wire in the stud. It is an OCD thing, neat freak, and I believe that they make better contact than twisted and screwed-up bunched copper that looked ugly.
When I have connected through bare wire clamped by the terminal post I have found that no matter how tight I screw the cap, after a period of time it can be tightened further, and again, and again - I donât know if it is the bundled strands shifting or the cap loosening, though it doesnât happen clamping solid flat connectors. Regardless not great. I donât like bananas (other than the ones I can eat!) So for speakers I use fork connectors (forked spades, gold plated for the reasons outlined in my earlier post, crimped and soldered to the copper cable. My amp and speakers both have gold plated speaker terminals.
Reducing change in materials (which happens on any signal path - itâs unavoidable) is desireable. For this reason, I prefer to match the banana plugs to the terminals.
I have a big box of Deltrons, both large and small bucket plugs and in nickel, gold, and silver.
So I use the nickel Naim plugs on the amp, and silver Deltrons on the speaker end on one system. Wheras another uses gold at both ends because that matches both amp and speaker terminals.
I believe we are on the same page. The gold forked spade connectors I use have two Alan key grub screws for clamping down the twisted copper conductor strands on each spade connector.
For anyone who isnât put off by 38 page research papers, this contains some interesting details about how and why silver tarnishes:
Comments on electrical connectors on pages 2 and 30.
As if this discussion didnât have enough complexity already, silver sulfide is a semiconductor - in fact, it was the first substance to be measured as such, by Michael Faraday in 1833!
A quick google for âsilver sulfide resistivityâ threw up a range (as one would expect for a semiconductor) from 1E-6 to 1E-4 Ohm-metres. Gold, along with most metallic conductors, has a resistivity about 100 times less than the lower of these limits. So, the answer to the OPâs question is that silver sulfide is about 100 to 10,000 times less conductive than gold.
Doesnât necessarily mean your ears will prefer one to the other, of courseâŚ
It can be discussed if the values for conductivity is for the material itself or when itâs bonded to a connector against another connector. The below is magnified gold plating. The actual contact surface is very rough. As I understand it the high polished rhodium plating Furutech use have less highs and lows meaning the actual contact surface under a microscope is greater. The best value would to look at would be if someone have made measures on connector to connector with different platings. Does it exist?
I also believe the liquid that some sell for connectors (not cleaning) makes the contact surface greater since it sits down in the âvalleysâ in the plating.
Iâve used Deoxit in an attempt to stop dissimilar metal erosion, it didnât help. The final fix was fit a new gold plated terminal plate and replace the nickel Naim plugs with gold plated Deltrons.
That aside I only use Deoxit once and only once on new 13A sockets.
Never on speaker or DIN & RCA
Like I said at the start, the connectors I use hardly show any sign of tarnishing after 8 years and even if there is, a quick pull out and insertion cleans the contact. This cleaning method is the same for Naim gear which doesnât have silver. Once the connectors are inserted, they become far less exposed to oxidisation (see above). So nothing has changed and looking at scientific studies about silver sulphide becomes kind of irrelevant.
A few points;
Depends if the silver plating is 100% silver. i.e. sterling silver contains copper alloy, which is still a great conductor and makes the silver more resistant to oxidising.
The method of plating makes a difference to the connector.
Whether the plating is directly applied or an intermediate layer is applied to the connectorâs base metal, makes a difference.
The base metal makes a difference. Many connectors use a base metal of brass or alloy, plated, then a thin plating of gold or silver. Decent connectors use pure copper. When making my mains block, I used all one piece C101 pure copper rails, as this was the best conductive copper I could find. I also deburred every single edge of every contact point in the socket construction, so when the plug is inserted, it would sit as flat as possible with no high points.
Looking at a generic magnified image of a plating tells us absolutely nothing. Itâs the quality of the surface and plating of each connector youâre using that makes the difference. Looking at my Furetech mains plugs, theyâre pretty naff. Looking at my Audioquest silver plated RCAs, theyâre a perfect mirror finish.
Letâs get this straight and basic. Gold is not used for sonic purposes.
