Post dedicated cicuit sound problems

If your electrician is returning I’d suggest asking them to install a second small consumer unit. Split the meter tails with a Henley Block, and take the earth from the new unit directly back to the meter and not via the existing CU. I use a 50amp type C MCB on mine. As the wiring is already run it’s a small job to split the tails and wire the new radial to a second CU.


Hi Aurinia
I am thinking of getting a dedicated hifi radial too.
I’ve been quoted £1250 for 4 unswitched sockets on a run of around 8M of 10mm cable, plus 2 extra sockets on the dirty main ring for the TV stuff, plus plastering.
I need to decide whether to invest in another box or a circuit.
One possibility might be to get an electrician who’s experienced in installing hifi circuits to have a look at it?
Either way, good luck with it and please let us know how it progresses.

Sounds about right. Mine was a bit less, but the wiring was in place, save for the extra earth run around the outside of the house and the new CUs.

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Why do people persist in using 13A mains sockets with 10mm2 cable? Would it not be better to convert to industrial heavier duty sockets?
image image
These are readily available in 240V 16A, 32A or 64A versions (32A pictured), which will have cable fixings better designed for heavier cables, and greater electrical contact surface, at least in the higher rating ones, while also preventing unintended plugging in of inappropriate items giving the bearing in mind that one day you might not be the cognisant person around when something is moved.

They are not even particularly expensive, about £10+VAT each - though of course when the hifi marketeers cotton on and fit them to their trailing leads with a bit of graphemes dusted on they’ll cost 10 times that…


A few years back, my dealer suggested running a single 10mm radial and then using a star-earthed distribution block. Food for thought.

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Ive installed numerous dedicated hifi mains and what you are describing sounds exactly like the new circuits are burning in, assuming it has been installed correctly. This takes about six weeks on 6mm cable and much longer on 10mm cable. Also as mentioned already the circuits would really benefit from being on their own dedicated consumer unit.

My advice would be not to adjust speaker position or anything else for a while but just wait and listen to the changes in the sound over the coming days/weeks. Some days it will sound better but others it will sound worse again, this is normal burn in. After a few weeks of gradually getting better it will settle and sound the best you have heard it.


Do you still provide this service?

Would it be better to get an XP5XS or a hifi radial to use with a 272 and 150x?
(Assuming that they cost the same and one has no obvious problems with electricity supply to start with).

Nothing to add regarding the electrical advice already given, but I noticed that your smoke detector is off in the pictures and I presume this was a temporary thing?

If you’re planning XP5XS for the 272, I would advise to addition carefully, you will easily change your mind as you go up the PSU hierarchy.

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I actually tried this. It sounded dire. Left it to run in for ca 400 hours but still sounded terrible. Changed the plugs back to some specialist 13A and it sounded better but still not great. Got rid of the 10mm2 cable and replaced it with Acrolink 7N stress free…aahhhh

Its not something I do for a living, Ive done this locally (I’m in Kent) for a few different friends, and for myself of course. It really has made a great difference to the sound once burned in.

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As far as I’m aware, such plugs are unfused, so would not be compliant with safety regs in a typical UK installation.

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Good point

I guess in a dedicated circuit with a suitably low rating on the MCB you may be able to do it legally, but best to tread carefully.

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Addendum - of course a single 10mm feed should do (via block) for a system, with any ‘noisy’ kit on other circuits (dedicated or otherwise).

FWIW/FYI, I have a dedicated ‘hi-fi’ CU with enhanced earthing, with 6 x 10mm radial feeds - all done by a qualified sparks many years ago. As other threads reflect there are options around the management of the supply.

My CU (MEM) has one bus bar and I understand others may have 2. I looked at retro-fitting another bar but this could not be done.

Many thanks for all the advice. For now i’ve decided to put it all away, take a break and come back to it refreshed. But I will get that breaker sorted out!

BTW it cost me £100 to have the circuit put in, hence a no-brainer to have it done. Simple run of about 12m of cable up inside the wall from CU, along the loft and down inside the wall to where I wanted it. Benefit of stud walls I suppose (about the only one). Not sure how it could cost £1250?

Wow - £100 is not expensive.
I would have thought the materials would have come to £100.
Mine would also include significant travel for the electrician, a CU, plastering, etc.
But, yes £1250 seems way OTT (esp. up North), which is why I politely declined the offer within minutes of receiving the estimate.

Maybe I found it difficult to get quotes and only received one very high quote because I sent a wiring diagram and a short list of things I wanted such as 10mm wiring and a separate CU?

What are the advantages of a CU with 2 bus bars?

A reasonable price for a standard installation including materials and labour should be circa £400 - £500.

£1250 seems way OTT.