Naca5 solder quality

Sorry, Peter, brain fade! I meant banana plugs,

I appear to be the one going bananas!


Yes as Skeptical said above…
Anyone wishing to solder a 4mm plug, A simple, effective way is just to use a wood block with some 4 mm holes drilled in it. Wood is a very good thermal insulator in this particular situation and that’s one of the reasons why I get good results!

KR, Peter


The soldering is fine.

The only problem is the broken strands on one of the joints.

I remember when I first saw POS on the plug. Thought it was so funny. :laughing:

I gave up on trying to solder NACA5. I use Siltech solderless Deltron-style terminations on amp and speaker ends. The sound is not worse in any case. The advantage is – unlike the Naim Deltron connectors – they don’t slide out of the amp and speaker terminals as easily.

Honestly, I think the Naim plugs and thick cable like A5 is one of the simpler soldering tasks. The pins lend themselves well to a tight and easy to apply solder fixative.

While the methodology for Naim plugs and reliance on a cable of a certain thickness is unusual, it’s definitely on the easier end of the spectrum of soldering tasks.

I must have soldered a thousand plugs in my time, and lately I’m more likely to being doing fiddly SMC work. I’d rate Naim plugs as No.2 for ease of doing a good job next to small gage cable into small bucket Deltrons.

Looking at the pic, it looks like a poor job. But we don’t know the real age of the cable. It may have been under strain in a corrosive coastal environment for 30 years resulting in sheath recession and strand breakage. Or it could have been bodged 12 months ago.

If you do ask someone to redo it, just make sure they are aware of the procedure for that pin type. Being an experienced solderer isn’t enough. You have to know the steps for that plug, dead simple though they may be.

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Although not particularly neat, that in itself should not be an issue, as long as spare strands are cut away.
However the biggest observation to me is that the joints look dull, as such looks like it was done with no added flux and a not sufficiently high temperature on the wire… perhaps not a powerful enough soldering iron or large enough soldering tip.
The solder connection should be shiny, and the solder should flow smoothly up the copper strands. For this sort of job you need a powerful iron and added flux, and not rely on the flux in the solder which is more suited for small electronic components.
A non shiny connection can become brittle and break. Any flux build up on the outside of the joint should be brushed away. Although this example is possibly just about acceptable, I would re do… but practice first if you are not familiar soldering. Soldering thick wires requires a different heating technique compared to electronic components. Loads of examples on the web.

Just another thought, for what it is worth (not much I guess)…

When I re-solder the terminals on the Naim Speaker plugs, I trim back the cable and strip just enough insulation to have bare wire in the plug pin slot, twist the conductors, and as an additional step so far not mentioned, I de-solder the old solder from the slot, and take a file to the slot to remove the soft solder and leave a fresh surface and maximum width and depth, and additionally I use proper lead solder, which works much better.

But for H&S aspects, I am not trade or organization, just on my own and capable of assessing the risk to my health using lead solder, which will do a better job.

Don’t try to twist the wires. It just makes them much harder to fit into the slots.

Lead solder is easier to use. With any solder you should work in a well ventilated area. A small fan blowing the fumes away from you helps.

Naim plugs are not that expensive. I would start with new ones. If you re-use old ones get a solder sucker to remove any old solder deposits.

If you haven’t done it before, cut a couple of inches off the end and use them to have a couple of trial runs. Chances are you’ll mess it up on your first attempt.

If you need to buy a new iron it will cost you more than it would to pay someone to do it properly.

Strand breakage doesn’t appear to be the case as there are no visible broken ends soldered to the pins, so it looks as if someone couldn’t get the full bundle to fit in the slot and cut a few strands back instead of soldering perhaps on top.

Well, I knew my suggestions were not worth much…

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