An excellent local electrician has agreed to install a HiFi radial for me.
He used to work for the electricity board so knows his stuff.
The plan is to split a new branch from near where the supply enters the property and feed that to a dedicated CU, then have a single cable to an unswitched double socket.
This cable will run horizontally along the outside wall of the house in an armoured pipe from the existing meter box and then straight through the wall into the sitting room where the HiFi racks will be set up (after the socket is installed).
Then use a hydra cable or block into my 7 Naim boxes.
I would like to specify the CU, the cable, and the socket type that are likely to give the best sound.
Should the front of the socket be flush to the wall - or could it be just screwed to the wall?
What make of CU, cable and socket will be likely to give the best sound quality?
I can’t advise re spec of equipment but i would go for a surface mounted back box and socket if it doesnt interfere with your rack.
It negates chasing out your wall and is easier to relocate (and repair the wall ) if the situation arises.
At the CU side it’s easy. A Doepke DFS Audio Grade diff switch and an MCB from Gigawatt. You won’t find better for audio purposes. They’ve passed by in various topics earlier.
I went for an MK metal CU, with 10mm SWA cable going to an MK unswitched socket that was flush to the wall for best aesthetics. For SQ reasons I chose not to have a surge protection device in my CU. Used a 32A RCBO type C.
There may be better sockets, but thats a step too far at the moment, and MK are well respected.
Good luck with the move Jim and glad to hear you’re getting dedicated mains sorted too.
Can’t help with what gives the best sound. I just left it to my Electrician to fit his favoured components based on my requirements and compliance to the regs at the time (17th edition).
Back in the day, Memera were the consumer units to beat. They still exist under the Eaton brand but whether they are still good I don’t know. The most important thing is an uninterrupted cable from the CU to a good unswitched socket, which is likely to be MK. Ensure the earth from the new CU goes direct to the meter box and doesn’t go via the existing house CU.
Re the CU aspect, I read many years ago that a CU with 2 busbars is better than having one (some could be retrofitted) but I’ve never been able to find one which offers this.
I asked my own sparks to see if another busbar could be fitted to my MEM unit but seems not.
Yes - but my knowledge on this is very limited. FYI (I think you may know?), I have a dedicated CU with 6 gangs/10mm feeds from it via a MEM-branded unit.
My installation was done c.19 years ago when, how shall we say, some Forum members were sharing wiring diagrams around the place - of course, not allowed now for well- understood reasons.
As the Forum responses bear out, the perplexing issue for me is whether one 10mm feed (from a separate CU) with a distribution box (e.g. Chord - as mentioned on other threads) is better (however you define that word) than having the same in-line feeds from a busbar(s) within the CU?
It was interesting to read (IIRC) that one of the blocks uses separate busbars for cabling and Chord appear to suggest that simple star wiring is not the way to go.
Of course, within all this, optimising the earthing mustn’t be over-looked.
I think Naim recommend the single circuit in to block approach(?)…but if you go the Chord route that’s a far more expensive gig.
I have 2 busbars in my memera consumer unit. They were available from mem as a spare part and simple fit over the top of the existing one to effectively double the size.
Russ Andrews sells an ‘Upgraded RCD Consumer Unit’ which looks like a Hager model. I’m sure your sparks could buy the same or similar directly at a saving.
For the CU I would use a small Hager. You can use the RCCB as a main cutoff switch so don’t buy a switched CU.
For switches, the Doepke RCCB and Gigawatt MCB are by far the best devices of their kind that I have tried. Expensive but excellent for audio and worth the money in terms of SQ.
You don’t need any buss bars as the Doepke and Gigawatt when used together are incompatible as they have different cable entries.
In fact, buss bars are not an advantage. You want your Phase and Neutral split off via a Henley connector block in your meter cabinet. Both phase and neutral are connected to the Doepke, the phase output goes to the Gigawatt input and the returning Neutral goes straight back to the Doepke, no buss bars required.
For cable, I use Acrolink 7N P4030II because IME it sounds a lot better (more neutral, less intrusive) than any 6mm or 10mm T&E that I’ve tried previously but again its expensive, depending on how long a run you need. If you need a long run, then 10mm may give less voltage drop.
For sockets I use Furutech unswitched duplex Gold over solid Copper, which handles large gauge cable without difficulty and again seems largely neutral in terms of influence on SQ.
Be sure to go over the above with your electrician. As far as I know it meets the most recent UK code, but I’m not an electrician, so check!
Is there a shortest length of cable that I should use to run from the outside of the cavity wall to the inside where the hifi sockets and racks will be?
Does it need to be at least 1M or 2M long?
(My electrician is coming within the next hour to scope out the job).
I can’t see any problems with a short cable other than that putting the rack in close proximity to your main consumer unit may put it within range of any RFI or other nasties. Presumably there is a separate consumer unit dedicated to the audio stuff. Your sparky will likely be aiming to keep the tails that feed this reasonably short as they are unprotected by RCDs etc.
I guess you may find it harder to persuade your sparky to use thicker cable if the run is very short. If he’s unfamiliar with this stuff he probably already thinks you’re bonkers
