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Reliable Copper Banana Plugs in Europe?

olieb

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I found those of QED screwlock ABS are very good and not that expensive. Or find some Neutrik ones (but i don't know if they are still made). Most on amazon are very fragile build i have to say, and come loose very fast.
As somebody already recommended. Stäubli, certified for 32A.

These are with screws, I would prefer to solder the wires though.

1702115861255.png
 

antcollinet

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The specific thing to avoid in speaker connections is ferromagnetic materials. In an ASR review of an admittedly high power amp, a ferrous connector increased distortion. I'm not sure it would be audible, but no point in knowingly doing something wrong!

Edit. Link added: Post in thread 'Buckeye 3 Channel Purifi Amp Review' https://audiosciencereview.com/foru...-channel-purifi-amp-review.40293/post-1421549

The specific thing to avoid in speaker connections is ferromagnetic materials. In an ASR review of an admittedly high power amp, a ferrous connector increased distortion. I'm not sure it would be audible, but no point in knowingly doing something wrong!

Edit. Link added: Post in thread 'Buckeye 3 Channel Purifi Amp Review' https://audiosciencereview.com/foru...-channel-purifi-amp-review.40293/post-1421549

On the other hand - here is a test of binding posts going from no binding posts (just a straight wire)

Down to - literal - nails.


No audible impacts measured. Even the distortion comparision between copper wire (no posts) and steel nails showed negligable difference, and certainly nothing audible.

 

olieb

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The specific thing to avoid in speaker connections is ferromagnetic materials. In an ASR review of an admittedly high power amp, a ferrous connector increased distortion. I'm not sure it would be audible, but no point in knowingly doing something wrong!

Edit. Link added: Post in thread 'Buckeye 3 Channel Purifi Amp Review' https://audiosciencereview.com/foru...-channel-purifi-amp-review.40293/post-1421549
Maybe it's me, but I did not find mentioning of actual distortion in the linked post. There the question was, whether there is ferromagnetic material in the input section of a power amp. Answer of manufacturer: yes there is, we changed that and found no difference in distortion. But I did not read through the whole thread.
 

Killingbeans

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Could you provide a link?

Let’s try to quantify based on the second link I provided (please correct me, where I might be wrong):

a. 2 screws + banana contact resistance = about 0.0015 Ohm.
b. 14 Awg copper wire resistance about 0.008 Ohm/m.
= almost 19% reduction per 1m of a 14 Awg copper cable.

Now, I’m not an engineer, would we just divide the 19% by 2, if we use a 2m cable?

Think of it as quantity instead of percentage.

If you put a single grain of salt in a bottle of pure fresh water, and you put a "whopping" 19% bigger grain of salt in another identical bottle, it won't matter squat for the taste.

And we aren't even talking about taste here. It's just a miniscule amount of extra resistive load.

Open up a bunch of amplifiers and look at the internal wiring going to the speaker terminals (if not PCB mounted). It will often be "appallingly" thin stuff, and it gets even "worse" when you start calculating the cross section of PCB traces. Even the really wide ones. But it doesn't matter, because the lengths are so short.

If you really want to worry about something, worry about inductance. Although, that's not actually worth the bother either.
 

MCH

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Maybe it's me, but I did not find mentioning of actual distortion in the linked post. There the question was, whether there is ferromagnetic material in the input section of a power amp. Answer of manufacturer: yes there is, we changed that and found no difference in distortion. But I did not read through the whole thread.
I believe the find @MaxwellsEq wanted to point to is in the post linked below. Indeed a steel part in the binding post was causing distortion in a high performance amp.

Post in thread 'Buckeye 3 Channel Purifi Amp Review' https://audiosciencereview.com/foru...-channel-purifi-amp-review.40293/post-1478290
 

MaxwellsEq

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Roland68

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Specifically Locking Banana or BFA.
More budget friendly (my system isn’t super high end … yet).

Most of the stuff I see on Amazon in Europe is Nakamichi. I just saw a video proving with a magnet that they are in fact not 100% copper:

This made me think bare 100% copper wire might be better than ‘maybe copper’ banana plugs.

So, do you know any plugs (or reliable brands sold in Europe) that are 100% copper? It’s often difficult to find some of the brands mentioned on ASR, as they are US specific.
Before anyone replies to this post, I ask that you read and consider the last section.

In order to decide what you can or want to buy, you first have to understand what the problems are.
Basically, assume that almost all plugs you get from the usual sources have the problems listed below.
In my experience, this is especially true for plugs under €/$10 each.
The exception is often hollow bananas (but unfortunately not all) which are made of pure copper, are uncoated or ONLY silver-plated (without nickel plating underneath) and can only be soldered, not screwed.
But be careful, a few months ago I had cheap copper-colored hollow bananas in my hand that were magnetic and had a nickel layer under the copper plating.

1. Fundamental problems
- Nickel is always magnetic and has a higher magnetic influence in alloys than iron.
- Pure copper oxidizes very quickly without a protective layer.
- Silver tarnishes over time and forms a patina on the surface.
- Oxidation and patina create a contact resistance that ranges from several 100 ohms to the megaohm range, or even completely isolated.

2. Gold plating or rhodium plating
- Almost every manufacturer has a nickel layer under gold plating or rhodium plating.
- This coating is necessary as a barrier layer because copper and coatings diffuse into each other.
- Nickel is always magnetic.
- There are methods to minimize or eliminate the nickel layer, but these methods are so expensive and time-consuming that the coating per plug is more expensive than the complete plug from other companies.

3. Materials of connectors
- Pure copper is the best material for audio connectors.
- Pure copper is difficult to work with because it is very soft. Especially with such small and thin-walled components.
- This is why phosphorus copper or other copper alloys are often used, often with nickel (see point 1).

4. Everything said above also applies to ferrules for stranded wire and speaker terminals


I couldn't detect any magnetic properties with the high-quality plugs from Inakustik, but all plugs are in the 2-digit price range per piece.

Hollow bananas made of pure copper, uncoated or silver-plated, are inexpensive and good, but they have to be soldered.
To do this, it has to be polished every 6 - 12 months, silver only with appropriate care products.
You can coat uncoated copper plugs with a thin layer of real copper paste (please only use high-quality branded products). This protects against oxidation and even slightly improves the transition resistance.
It doesn't get any better even with the most expensive plugs.


However, it must also be said very clearly that well over 90% of the plugs used have these problems/characteristics.
Does it have audible effects?
Everyone can and should form their own opinion on this.
 
OP
C

CauliflowerEars

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The specific thing to avoid in speaker connections is ferromagnetic materials. In an ASR review of an admittedly high power amp, a ferrous connector increased distortion. I'm not sure it would be audible, but no point in knowingly doing something wrong!

Edit. Link added: Post in thread 'Buckeye 3 Channel Purifi Amp Review' https://audiosciencereview.com/foru...-channel-purifi-amp-review.40293/post-1421549
Ah, thank you. That's a very good point.
Is there a good way an amateur can check/make sure a plug doesn't have ferromagnetic materials?
 

MaxwellsEq

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Ah, thank you. That's a very good point.
Is there a good way an amateur can check/make sure a plug doesn't have ferromagnetic materials?
You need an incredibly complicated and expensive piece of test gear...

... a magnet ;)
 

ta240

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You need an incredibly complicated and expensive piece of test gear...

... a magnet ;)
Now you've looped back to the OP's original concern. Finding non-magnetic connectors without having to buy them first to test with a magnet.

In the same 2 page thread, a post has been referenced that says a chunk of steel as a connector doesn't make a difference and another post showing that chunk of steel as a connector does make a difference.
 
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Roland68

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Moonbase

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Continuity is a good start and also their are no short circuits/breaks if the connector is moved around
 

Roland68

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Ah, thank you. That's a very good point.
Is there a good way an amateur can check/make sure a plug doesn't have ferromagnetic materials?
Get a so-called pot magnet made of strong neodymium material with a diameter of approx. 20mm. The magnet can be larger, but not much smaller.
This allows you to detect even small amounts of nickel or alloy components.
With small amounts of nickel, you only notice a slight attraction, but if you can pick up a plug with it.... :facepalm:
 

MCH

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hey guys, today i received a bunch of these nakamichi banana plugs that are all over the place in aliexpress and reminded this thread.


Took a strong neodymium magnet and yes, can confirm they are very very slightly attracted, but the force is really weak.

Tested then some inakustik i have in use with my speakers and these are not ferromagnetic at all, not a little bit


And as i was at it, tested the binding post of my speakers (KEF LS50 Meta), and i tell you something, the metallic inner part of the part pictured below is at least as much attracted to the magnet as the cheapo bananas, if not more. No need to say that i will sleep tight tonight and continue enjoying my Kefs, but just wanted to bring a reference point to the discussion.

IMG_20231214_170714.jpg
 
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howard416

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I don't understand. If you search amazon.de you find dozens of banana plugs of all kinds and brands. Nakamichi not more prominent than others. And all these plugs are essentially made of brass (CuZn) , sometimes nickel plated sometime gold plated.
If they react to a magnet chances are that there is some nickel part too. Or a tiny piece inside (for the springy part) made from iron or (stainless) steel.
All this is perfectly fine for conducting electricity.
Iron (or maybe some steel alloys) add distortion, anywhere from 0-3 dB or more. Look up the issue Buckeye Amps had with steel(-tab?) binding posts. It wasn't too fun for him, I think. https://www.audiosciencereview.com/...502mp-8-channel-amp-review.43584/post-1546050

EDIT: I see this was already mentioned. Well, anyway, BFA plugs from Parts Express work fine for me, I think you should be able to get known-quality ones from there or elsewhere.
 
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Roland68

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Iron (or maybe some steel alloys) add distortion, anywhere from 0-3 dB or more. Look up the issue Buckeye Amps had with steel binding posts. It wasn't too fun for him, I think. https://www.audiosciencereview.com/...502mp-8-channel-amp-review.43584/post-1546050

EDIT: I see this was already mentioned. Well, anyway, BFA plugs from Parts Express work fine for me, I think you should be able to get known-quality ones from there or elsewhere.
Unfortunately, at this price you have to assume that these plugs also have a magnetic nickel layer under the gold plating.
 

howard416

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Unfortunately, at this price you have to assume that these plugs also have a magnetic nickel layer under the gold plating.
Quite possibly. I would love to see comparative measurements (xHD vs frequency vs power, 19+20 IMD, N) of similar gold-plated connectors having and not having a nickel under-plate. I have a gut feeling that the distortion effects from nickel (at least for just a thin layer) don't show up until higher frequencies, maybe even above the audio band entirely, but that could just be wishful thinking.

 
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sq225917

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Nearly all gold played and silver plated parts have nickel underneath, its prevents the plating from diffusing into the copper and exposing it to air, humidity and prevents corrosion.

Worrying about plug conductivity is a waste of time. Think of all the solder in a circuit, it's conductivity rating is about 15% that of copper. A few fractions of a miliohm is a none issue.
 
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