Solder is around 1/8 the conductivity of copper, no matter how much you use.
I'm confused on Banana Plugs (Solder them yourself???)
- Thread starter FriedChicken
- Start date
I use Kester 5% silver solder. The other 95% is tin. They say that less than 3% silver is essentially worthless.
FriedChicken
Active Member
If I have 8x the surface area of the solder, it's effectively identical to copper.
Additionally, see my other point about length of travel. For long connections (i.e. speaker cable) you need a sufficient amount of conductor, see here:
I switched from 14-gauge copper to 12-gauge copper for my 10-ish-foot cables. The resistance should have moved from ~0.023Ω to 0.016Ω, although my reference is for a solid copper wire, not a stranded copper wire.
A solder joint is not going to have an appreciable resistance over its... what, 1/64" distance? Basically approaching zero.
Not only that, keep in mind, inside the amplifier and the crossover of the speakers is... you guessed it, solder. It doesn't matter insofar as resistance is concerned.
If the concern is about resistance to the point where the OP is about using a plated steel banana plug, the solder is also significant.
In crossovers, in circuit-boards, in most electrical and electronic assemblies there is first a mechanical connection and then solder. This is true of wire on terminal as well as pin-in-hole circuit-board assemblies.
In crossovers, in circuit-boards, in most electrical and electronic assemblies there is first a mechanical connection and then solder. This is true of wire on terminal as well as pin-in-hole circuit-board assemblies.
FriedChicken
Active Member
I'm not sure this is true... neither for SMD/SMT, nor through-hole
I am sure, it's what I did for the first 20 years of my engineering career.
In SMD assembly it is different than through-hole, by necessity however (the process doesn't create a direct contact) not by design. The rule however, when possible, is mechanical connection then solder. I designed our company's first SMT product around 1986 and the process has compromises necessary for how it is soldered in the production environment.
It's "splitting hairs", but worrying about whether there's any iron in the banana plug is also splitting hairs, so the argument that you are okay with the small resistance of solder but not okay with a base-metal under the plating (where the plating carries the signal) that has iron in it is at best inconsistant. Next we'll be discussing skin-effect in plated connectors as if it's high-frequency / RF instead of simply audio frequencies?
In SMD assembly it is different than through-hole, by necessity however (the process doesn't create a direct contact) not by design. The rule however, when possible, is mechanical connection then solder. I designed our company's first SMT product around 1986 and the process has compromises necessary for how it is soldered in the production environment.
It's "splitting hairs", but worrying about whether there's any iron in the banana plug is also splitting hairs, so the argument that you are okay with the small resistance of solder but not okay with a base-metal under the plating (where the plating carries the signal) that has iron in it is at best inconsistant. Next we'll be discussing skin-effect in plated connectors as if it's high-frequency / RF instead of simply audio frequencies?
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sound hound
Super Member
Yes, some are ferrous, some are just poor conductors they will subtly distort the audio signal, it won't be a vast difference but often some diction becomes unclear audio is smoothed over detail is lost. I spent 20 years listening with those links in place wondering what people were talking about when they mentioned things like soundstage, wondering why I couldn't hear fast lyrics turns out I could it just it wasn't being reproduced clearly.
If you look at resistors and capacitors from audio companies like jantzen and mundorf amongst many others, they often feature copper or better leads.
Unfortunately given high metal prices the amount of ferrous materials in hifi seems to get worse. If you look at an old amp you will often see copper bus bars to speaker terminals, these days a cheap amp is very likely to have ferrous on the outputs.
mrehorst
Super Member
Soldering is entirely unnecessary. I use this type of banana plug- they come branded as well as "amazon basic". They provide a very good mechanical compression of the wire in the connector, and they'll handle up to 12 gauge wire. You can get them as right-angle plugs, too.
Worried about them being magnetic? Someone's been watching too many youtube videos....
Whatever you do, don't get this type:
The cute little spring part that goes into the socket on your speaker will collapse permanently and the plug will wobble around loosely in the socket.
Worried about them being magnetic? Someone's been watching too many youtube videos....
Whatever you do, don't get this type:
The cute little spring part that goes into the socket on your speaker will collapse permanently and the plug will wobble around loosely in the socket.
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I feel like this gets lost and should be mentioned more often. I trust my instructor who told us it's the mechanical connection first that ideally creates an oxygen free connection, then the solder keeps it all sealed up and in place. He used the wire wrapped square post as an example.
I guess I'm used to it but all hobbyist\pro videos on YT show these people sticking a lead thru the hole and then they just smack some solder on it. Now me, hard to see in the photo but I generally (not all the time) do a bend on the lead to get it down to the pad then I solder it. Yes, of course it's a pain the ass to come back and remove something but that's quite uncommon to have to do that.
I'm sure a couple of solder joints carrying a low level signal by solder thru a few joints is no big deal. And maybe even the signal thru 50 solder joints can't be heard, I don't know. I just try to follow some of the technics (<joke) that I was taught.
And the banana plugs I've soldered, I used 12ga wire which barely fit (in fact, I might have cut a couple conductors off to get it in), then I gave it a light crimp (hammer LOL) and then I soldered. I don't like the screw barrels much but I have used them.
I think the most important factor (other than material used) is how well they maintain the 'spring'. In the past, I've used some that would deform after only one insertion. I've found that Sewell hold shape even after several in/out.
Personally, I prefer (and use, when possible) solid copper spade connectors. 1/4" copper industrial/automotive spade/fork connectors can be found on Amazon, cheap.
Personally, I prefer (and use, when possible) solid copper spade connectors. 1/4" copper industrial/automotive spade/fork connectors can be found on Amazon, cheap.
FriedChicken
Active Member
I mean to be clear here, the motivation for soldering the banana plugs onto cables is not some magical better contact, it's because I don't want to spend a lot of money for something that in my opinion should cost next to nothing.
Also, re: soldering connections mechanical vs solder:
I taught myself to solder using Pace's 1960s (70s? 80s?) vintage instructional videos.
I don't recall any specific mention of ensuring mechanical contact.
Also, re: soldering connections mechanical vs solder:
I taught myself to solder using Pace's 1960s (70s? 80s?) vintage instructional videos.
I don't recall any specific mention of ensuring mechanical contact.
ConradH
Lunatic Member
I don't mess with my system for years at a time and I find that screws on stranded wire are unreliable. If I'm going to use screw-type dual banana plugs like Pomona, I use this method, also with all my lab equipment:
1) Find some 14 ga Romex in the garage.
2) Strip out whatever length I need.
3) Clean the bare wire with Scotchbrite #7448 or similar until any oxidation is gone.
4) Cut 1/2" pieces (or whatever is needed). File ends if sharp or use semi-flush cutters so they aren't.
5) Using a third hand clip, hold the wire and make a wrap of the stranded wire around one end. Use additional rosin flux if necessary. Solder.
6) Remove all flux residue with alcohol.
7) Insert solid wire in the side of the banana plug and clamp securely.
Takes longer to describe than to do, but it results in highly reliable connectors. It's particularly good with things like 6.5 digit meters, where small problems show up quickly. Different connectors will need different techniques. There is also some relation between how much you pay and how well they work. I suspect those Sewells are about a thousand times better than most of the import junk you see.
1) Find some 14 ga Romex in the garage.
2) Strip out whatever length I need.
3) Clean the bare wire with Scotchbrite #7448 or similar until any oxidation is gone.
4) Cut 1/2" pieces (or whatever is needed). File ends if sharp or use semi-flush cutters so they aren't.
5) Using a third hand clip, hold the wire and make a wrap of the stranded wire around one end. Use additional rosin flux if necessary. Solder.
6) Remove all flux residue with alcohol.
7) Insert solid wire in the side of the banana plug and clamp securely.
Takes longer to describe than to do, but it results in highly reliable connectors. It's particularly good with things like 6.5 digit meters, where small problems show up quickly. Different connectors will need different techniques. There is also some relation between how much you pay and how well they work. I suspect those Sewells are about a thousand times better than most of the import junk you see.
Another nice thing about the Sewell set screw type is that no matter how tight you torque them, they will not strip; unlike other's I've used.
For those concerned about the set screws loosening over time, apply a drop of loctite.
I use these, although a different brand. Scored a pack of 20 for a buck from an audiophile estate sale about 10 years ago and the ones I’ve used are still working great.
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