PSA: Dorman Quick Disconnects (Fastons) aren't really copper

Gardenstater

So unfortunately I'm still trying to find some audiophile grade fastons for making quick disconnects for the MW6500 and Peerless Tweeters in my 7Bs. The search will have to continue because I tested one of these Dorman ones sold at Autozone, Pep Dudes, and Advance Auto Parts and it failed. I destroyed one by honing the end nice and flat and sharp with my diamond hone and then I took an old 1979 copper penny that had a nice brown patina on it and proceeded to easily make a nice and pretty deep scratch in it with the end of the faston. It felt like it was very satisfying cutting the penny (perhaps unsatisfying in this case?). Also, I don't know if the pic shows it well but the color of the ground end was very yellow/gold and not brown/red. So, although they don't say on the package that it is a pure copper conductor or even copper for that matter and only hype the gold plating, it does say on the Dorman website and the Autozone website that the conductor is "Copper". Not copper alloy or brass and I wonder if this is fraud or can they weasel out legally by saying that it doesn't say so on the package?

VR3

Just solder them directly if it bothers you

Gardenstater

Well yeah @VR3 but the whole idea was that I wanted to make it easy to do future midbass and tweeter swap outs, and the USA made Peerless I purchased which was from a later serial # pair of 7Bs has bare tabs that were never soldered so apparently Polk switched to using fastons at some point instead of soldering. I have the crossovers from the same speaker and it has fastons on the wires.

mhardy6647

I am shocked. Shocked.




maybe try https://www.partsconnexion.com/?

Gardenstater

This just might be the only true pure copper faston avail. and it is the wrong size for Polk drivers, being tab size 0.250" x 0.032", from Furutech and about $3.12 each.:

http://www.furutech.com/2014/03/27/8789/

When you go to their smaller size of 0.187 tab (no 0.110's for tweeters) they say they are "Phosphor Bronze". Phosphor Bronze doesn't even have the conductivity of Brass (about 15% IACS vs 28% for Brass). Ya can't make this stuff up. I have no idea what is meant by Alpha Phosphor Bronze, probably some made up marketing term. Tellurium Copper, which you see occasionally in audiophile grade connectors (I haven't found a faston with it) has 90% IACS conductivity, which puts it above the gold plating at least, which is 70%.

http://www.furutech.com/2013/02/02/1659/

https://www.bluesea.com/resources/108/Electrical_Conductivity_of_Materials

ZLTFUL

Typically, the conduction only happens on the skin surface of the conductor.
In wire, this is why silver clad copper has different conductivity than plain old OFC or CCA (Copper Clad Aluminum).

Same is the case for your quick connects from Dorman. The gold is the primary conductor while the "core" is primarily there for support strength and longevity.

Rhodium plated binding posts also come to mind.

See: Skin Effect
https://en.wikipedia.org/wiki/Skin_effect

Gardenstater

@mhardy6647 I had checked there but apparently I missed these WBT ones that claim pure copper (for the $2.50 ea. price they better be) and they are 0.110 tab size which fit our Peerless Tweeters. Thanks!

https://www.partsconnexion.com/WBT-82855.html

And these should 0.187 tab size ones should fit the MWxxxx midbass drivers for $3.00 ea.

https://www.partsconnexion.com/WBT-82856.html

mhardy6647

De nada.

Partsconnexion is on the other side of the border but they're good folks in my (albeit limited) experience to deal with. They have a broad stock of stuff that's sometimes hard to find any place else. Their website is a little tedious to negotiate, but it can be worth the effort. Do they have 'em in stock?

Gardenstater

Yep. Both say in stock. Thanks again.

Gardenstater

ZLTFUL wrote: »

Typically, the conduction only happens on the skin surface of the conductor.
In wire, this is why silver clad copper has different conductivity than plain old OFC or CCA (Copper Clad Aluminum).

Same is the case for your quick connects from Dorman. The gold is the primary conductor while the "core" is primarily there for support strength and longevity.

Rhodium plated binding posts also come to mind.

See: Skin Effect
https://en.wikipedia.org/wiki/Skin_effect

In this case that's not correct * because the mat'l thickness of these Dorman fastons is 0.011", which puts it as comparable to a 29 gauge wire. If you look at this chart you see that *skin effect* which is a function of frequency and material dimension, would not come into play until a frequency of greater than 210kHz!

https://www.powerstream.com/Wire_Size.htm

* Unless a chart of skin effect for brass wires would be different than for copper wires.

PS: Why would anyone pay such high prices for billet copper Cardas binding posts and the like if it was as simple (and cheap) of a solution to apply a gold plating to a crummy conducting core material?

PPS: Think about what it would mean if it were true that all the conduction is occurring at the surface ie. within the gold plating which is only microns thick. What would be the effective DCR resistance and gauge of such a conductor? Pretty darn high resistance / small effective gauge.

ZLTFUL

You do realize the chart you linked is an AC chart? Right?

And since speaker wires/binding posts/banana plugs/etc are moving a DC signal, the frequencies are completely different.

Skin effect is more of a factor in a DC circuit than an AC circuit.

But I am no electrical engineer...but I did stay in a Holiday Inn Express several years ago once.

pitdogg2

A little light reading
Taken from here

https://www.mcru.co.uk/the-conductivity-of-metals-used-in-hi-fi/

Conclusions

Gold plated, silver plated or pure copper wire end terminals?
Gold is a lesser conductor than copper, by 40%. So, gold plated copper is no better, electrically, than pure copper. Still, there are gold plated pure copper cable end terminals, which are in turn worse than silver plated cable end terminals. Since the un-plated pure copper terminals oxidize over time, gold plated terminals will sooner or later be superior, since they do not oxidize. However, silver plated cable end terminals are the best choice, because they keep their superior conductivity even when oxidized.
Rhodium plated plugs?
Rhodium is a precious metal from the platinum family. It is hard, acid-resistant, and has a very high melting point (1964°C). Compared to other platinum metals, it is a very good conductor, but still only half as good as gold and just one third as good as silver. Therefore, it is misplaced as a coating in a domestic environment. Its sound characteristics are often described as harsh and analytic. It does however have its justification in industrial environments with high temperatures, for instance near blast furnaces, where it reliably does its job at temperatures where gold would already start to melt (which it does at 1064°C).
Nickel plated or “naked” brass?
Standard brass (40% zinc, 60% copper, CuSn40) is about as good a conductor as nickel, as long as it is not oxidized. With oxide layer, it conducts worse. However, the sound is “smoother” without nickel – therefore, naked brass plugs have a justification, as long as the listener is prepared to clean them regularly. The necessity to do so can be removed by silver or gold plating.
Plugs from phosphorus bronze?
Phosphorus bronze is a quite hard material and is held in high esteem for its tonal virtues when used for church bells. However, it is a lousy conductor. Nevertheless, there are now Japanese plugs in the market, which are made from phosphorus bronze, and bear price tags that were unseen before. I have not tried any of these yet, but am quite skeptical based on the aforementioned reasons.
Plugs from beryllium copper?
Beryllium is a highly toxic element. Beryllium copper is a (non-toxic) copper alloy, just as brass or bronze, and is the best conductor among the copper alloys. However, it is still much worse than copper itself. It has remarkable qualities for tools, and because of its springiness it is being user for the balance springs in mechanical watches. Because of this property, it is also a very fine material for banana and BFA plugs, where the quality of the contact depends on how tight the plug will sit in its socket. However, it is misplaced in mains plugs, where we have massive pins, and where the material cannot draw on its elastic properties at all. If looking for a material with better conductivity than brass, pure copper or silver would be the material of choice here – the two are not only better, but also cheaper, and non-toxic in the production process on top of that.
Solder or crimp?
Copper’s conductivity is six times higher than tin’s! Fine solder typically consists of more than 60% tin. Thus, a gas-free crimp connection is always preferable to a solder connection.

Gardenstater

@ZLTFUL Actually audio signals are much more AC than they could ever be described as DC. Here's people attempting to explain it, but basically an audio signal couldn't contain changing information if it were DC:

https://www.quora.com/Why-are-audio-signals-AC-not-DC

Holiday Inn Express is nothing to be ashamed of

delkal

By the time an audio signal comes out of the amp it is only an AC current of different frequencies. Speakers only work with AC. Any residual DC in the signal is bad and can destroy your speakers (DC offset). You can demonstrate this yourself. Hook up a battery to your speakers. The speaker will give a brief pop but then the woofer will just sit there displaced. No sound.

mhardy6647

Audio signals are AC, albeit often very asymmetric ones.

Gardenstater

I returned all the opened packages with some missing fastons to Pep Dudes and Autozone for full refunds. I showed them how on the Dorman and Autozone websites it said they were Copper Conductors. The one salesman made a valid point that they *may* have been copper at one time and got changed to brass for cost savings and they failed to update the website. Whatever, still no excuse.

I purchased the WBT's from partsconnexion in Canada for like 5x the unit costs, but I'm going to bet they really are copper. If not I'll go ballistic lol. Tomorrow my Chinese *Pure Copper* binding posts arrive from Amazon. THAT should be interesting

PS: I also purchased some Furutech pure copper crimping sleeves that I plan to use to attach the stub wires from the Danish Peerless tweets to my DIY 4N laminated copper male fastons, with a solderless joint. Turns out a fishing wire leader crimper is ideal. I think a really good crimp, especially with a small amt of silver platelet contact enhancing grease should make a more conductive connection than silver solder.

Gardenstater

In the future I will be using this material for making any Male fastons:

Gardenstater

Well WBT fastons I got from partsconnexion.com are NOT copper but in fact brass (scratches the shite out of a 1979 penny). Woulda thought for the price of 5x the unit price of the Dormans that they would be copper. Also this is the company that sells the $140 gold plated crimp tool. At least my Furutech crimping sleeves I got from them are gold plated copper and I can now put my DIY 4N copper male fastons on the stub wires of my Peerless tweeters by crimp process.

Gardenstater

Gardenstater

F1nut

I believe the reason no one makes pure copper fastons is it's poor spring retention as it's too soft. Hence, the use of copper alloys such as brass or phosphor bronze.

While I'm firmly in the everything matters camp in this case I think you are on a fools errand.

F1nut

PPS: Think about what it would mean if it were true that all the conduction is occurring at the surface ie. within the gold plating which is only microns thick.

Yet, you think that silver paste, which is applied on top of whatever metal it may be is increasing the conductivity?

Gardenstater

F1nut wrote: »

PPS: Think about what it would mean if it were true that all the conduction is occurring at the surface ie. within the gold plating which is only microns thick.

Yet, you think that silver paste, which is applied on top of whatever metal it may be is increasing the conductivity?

On a microscopic level it increases the conductivity. It is pushed out wherever there are no microscopic gaps, unlike solder which builds up a pretty thick layer of material which is far less conductive than the base material. So the answer is yes.

The stuff I am using is Silclear from Mapleshade but there are others that are much more expensive. They talk about how fine their silver nano-particles are as a measure of quality.

So Jesse, try some as a simple test. Try putting some on your batteries in flashlights and you will find out that there is no longer any need to smack the things to get them to light when the voltage wanes down. Also, charging batteries in chargers where they often lose contact. I polished my `110V AC brass plugs with 1500 grit paper and applied this stuff to the prongs and got better bass from my amplifier. The silver nano particle pastes are designed to use for removable contacts. I'm undecided on whether or not they are desireable in a cold weld crimp connection. If so, it would be necessary to use a minimal amount, but for sure it would be better than tinning and crimping or even crimping and back flowing solder into the crimp, due to the thinness of the layer of silver particle grease.

Gardenstater

F1nut wrote: »

I believe the reason no one makes pure copper fastons is it's poor spring retention as it's too soft. Hence, the use of copper alloys such as brass or phosphor bronze.

While I'm firmly in the everything matters camp in this case I think you are on a fools errand.

All of us audiophiles are on a fools errand I guess then. But it sure is fun ain't it?

I have speculated the same as what you are saying, here in the forum, but I'm not sure yet that it isn't feasible to make one out of hard copper. For some reason, on a metallurgical basis, pure copper can be had in soft and hard, despite the fact that it is not an alloy. Need to go back to my metallurgy texts to read up on the whys and wherefores.

Tellurium Copper, which is harder than pure copper and still pretty damn conductive may be the compromise that is needed.