I got used naca5 and had the amp end naim dual professionally soldered and I put the speaker end bare wire than tried with bananas the atlas rhodium expanding and the bare wire sounded much better. So do we really need banana connection speaker end.

Bare wire slackens with age. Nothing beats Deltron 4mm plugs :grinning:

1 Like

The bare wire will oxidise over time and need repeated stripping back to clean copper wire

Yes I have some deltron on order the bare wire does sound good but if I have to keep cleaning or cutting the cable not really practical.

Not only that, as Guinnless has suggested, you may need to check the connections of the bare wires at the speaker terminals from time to time as they may get loose. I used bare wires many years ago and at one point of time I realised the sound quality took a dip and the system didn’t sound good as before. I did all the checking and finally found that the connection at the speaker binding posts was loose. The cap was loose and not tight, and I could turn it half round to tighten it. Once the connection was sorted, the system sounded great again.

All my speaker cables now come with banana plugs.

Yes thanks I will put banana connection on the rhodium expanding I had on will be sold with the atlas cable I was using before naca5.

rhodium Isn’t very good for audio connections
Check the conductivity scale for materials.

I have RS/Deltron 4mm plugs on both ends of my NACA4 cables - and they have been there since 1982…

Get your bananas properly soldered and you don’t have to worry about loose connections.
Whatever plating is used on your speaker terminals, I would get plugs with the same plating to minimise the chances of corrosion. That might be nickel, gold, silver, rhodium or whatever.

1 Like

If you choose gold, there will be no corrosion whatever the other metal is. People seem to forget that for some reason or other.

If it’s actually real gold lol
But I hope people are unplugging all the cables in the system at least once a year to clean all contacts.

1 Like

ProAc use rhodium binding posts…

And what’s your point ?
Doesn’t make it right … Naim doesn’t and never did … maybe Naim is on to something… and anyway just go to the conductivity scale and see for your self.
Rhodium may have other strengths that I’m not aware of.


There’s a lot more to it than just conductivity, @HiFiFoFum. Rhodium isn’t very conductive, as you point out, but if conductivity was all that mattered, all connectors would be made of copper or silver. Rhodium is jolly hard, which is a good property for a spade or banana plug.

There’s also more to it than just corrosion resistance, @davidhendon. Two dissimilar metals in contact will produce a contact EMF (such as thermocouples rely on to work), hence why so many people recommend matching the metals of the cable connector and binding post.

It’s a situation which requires a number of material properties, of which no metal possesses the ideal combination so every choice must involve compromise. Welcome to the world of practical engineering.



Rhodium may not be the ultimate for conductivity but I doubt someone could discern sound differences in the short term (before oxydation) between different plating materials. Would have to ask Stewart Tyler about that. :shushing_face:

I also think it’s best to have the same material for plugs and connectors.

Yes well I had temporarily overlooked the contact emf point. But doesn’t the same problem arise between a copper cable, the solder and the surface material in the Naim plug?



Yes, of course it does, hence why I was keen on stressing the idea of compromise! The only other solution being to have every single wire and connector in your entire signal path from source to speaker coil made of a chemically identical material which, I hope we can all agree, might be desirable but would in no way be practical.

Those who advocate metal-matching would probably argue that, with all the other unmatched metals necessary in a practical system, minimising the number of dissimilar metal junctions is desirable. In engineering, a good maxim is that if you can’t eliminate an undesirable factor, you should try to minimise it.


1 Like

I believe the problem will only arise if the dissimilar metals are in the presence of an electrolyte and that results in galvanic erosion. Water is a weak electrolyte, and airborne humidity is enough to get the process started in my experience.
I used to work in an industry where salt laden air from winter road salt & marine environment would cause untold reliability issues if not managed.
Solder as part of an electrical joint, although it’s another dissimilar metal in the mix, is a barrier against humidity & electrolyte formation.

Did you solder the Atlas plugs to the wire or use a mechanical connection (e,g. screws). If you used a mechanical connection to the wire, that extra connection (between tinned copper and a very hard and dissimilar metal surface) is where the loss of quality occurred.

No the 2 screws nĂł solder.