Another dedicated spur question

I apologise in advance but I have another dedicated spur question.

If you wanted three double wall sockets (so 6 sockets in total) would you have a dedicated spur for each double socket or just one spur that then daisy chains to all three wall sockets?

You can run a wire for each, though you’ll have to explain repeatedly to an electrician that you really do mean that. However, most people seem to run one line from a Henley and dedicated CU to one twin-socket and then chain from there, or plug a power-block or Hydra directly into it.

My multi-wire version will be up and running for the first time after the plasterer has been on Saturday!


Thanks for your reply.

I’ve been following your electrical escapades on another thread and looking forward to your impressions once installed and up and running…

Every electrician I’ve spoken to refused to call it a dedicated spur or even recognise the term and referred to it using different electrical terminology that I can’t remember now.

I’ve yet to find an electrician who fully understands the principles and requirements of a dedicated spur for HiFi use.

Naim’s advice to me was to use a single 10mm cable from a single MCB in its own consumer unit, not multiple cable runs. It makes connecting the sockets a bit tricky, although not impossible, so that’s what I did and the results were very worthwhile.

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Hi @ChrisSU - that’s where I started. After lengthy discussions, the sparks suggested strongly that we use shielded 6mm throughout, rather than 10mm to one socket and then 6mm (or more likely less) out to 3 more sockets.

He did say of 10mm wiring that he had recently done a recording studio - and that got 10mm but not into a domestic socket/ plug arrangement.


Try calling it a ‘radial’ perhaps?


They probably consider a single cable originating from consumer unit is not a spur.

But, a cable originating from a ring, is.


I did suggest to Steve Hopkins of Naim that it would be much easier to run 6mm T&E but he insisted that based on their experience I should stick to 10mm if possible.

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I apparently need armoured cable outside, and that my have swayed the advice. If it turns out to be wrong, swapping the actual cables would be easy - it’s the installing of Henley and CU that takes the time.

As I understand it, there are systems and situations in which 10mm is a very good idea, esp if you have active 500s feeding some big panels, but much of the advantage is lost of you run 10mm and then step down to smaller wires. News to follow.


Steve’s advice to me was based on the NDX/282/200 I had at the time.

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40 hours to go until listening tests.


I suppose in the UK a Schuko mains block from a single wall outlet “might be” better than 3 double wall sockets.

I’ll explain… A single Schuko mains block uses one thirteen amp fuse at the wall whereas 3 double UK wall sockets would have six fuses in total.

A Hydra would do much the same.

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I will try multiple ways of plugging in, but expect that the Hydra feeding 4 Naim boxes in one socket and the rest in other sockets may well be best.


I’ve installed 4 dedicated spurs over the years, 3 for myself (different houses) and 1 for a friend.

Two aspects proved to be very important, if not the most effective. Avoid as much cable cuts, splits/junctions, fuses, screw terminals, sockets and connectors as you can. Every single one is decremental to the SQ. This is within local safety regs etc. obviously (I’m in a ‘Shuko country’ btw).

Second, in the numerous topics and post about mains, there seems to be less attention to the MCB(s) and differential switch(s) used while these parts have a substantial influence on the end result. There is a world of difference between standard off-the-shelf MCBs from the hardware store that electricians typically use and better alternatives for audio. The same is true for diff switches, if not more so.

In my experience these 2 aspects have a bigger influence on the end result (read SQ) than the exact type of cable used or even the diameter. (within reason of course).


The correct terminology is radial circuit.
A spur is totally different.
There is also different fusing requirements for radials and spurs.

BS7671 appendix 15 defines it.


I ran two separate cables from a separate consumer unit, one 10mm and one 6mm.
The 10mm goes to feed six individual un switched sockets, these are all star wired on earth, live and natural, using same length wires. This means that i dont get any plug in problems or plug in order to worry about as all are the same.
I then just plug my amp into the other separate 6mm supply.
This all works very well, was so much cheaper than a fancy multi box sitting on the floor, plus being in the wall no vibrations from the floor to worry about and a far neater install.

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Have you also got 10mm between the sockets or is that 6mm? And which type of socket did you use?


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No i got myself a secondhand Russ Andrews 6 way power block and butchered it up. It was far cheaper this way than buying separate single sockets. I did remove the filter thing from inside it and re used the cables that once daisy changed between it all. The cable was silver coated if i remember right and stiff to bend.

But it all worked out very well, cheap and was a nice way to do it all

I use 10mm multiple radials from a dedicated consumer unit. 10mm sounded much better than 6mm and one radial per piece of kit sounded better than daisy chaining sockets to a single radial. All of this was with star wired earth.