More opinions please - this time on mains power

As an aside, I thought the Chord blocks (S6/M6) need 16A power feeds and not the bog standard 13A IEC?

In the pics it looks like standard IEC though.

Unfortunately this was at a previoius property so no photographs possible. I agree the results were unexpected but I can only report what I heard. Yes it’s odd I agree.

Yes the Chord blocks require a 16A IEC. They come with a free give-away bog-standard cable fitted with a 16A IEC. Chord do not recommend it’s use but apparently it is supplied for legal reasons. Anway it’s this lead that was used at the demo to connect the block to the wall socket.

Thanks for all that. Please do pin down things to say/ ask first!

So you’d go double-socket on left wall. That could feed the existing 6-way block and Hydra with ease, or I could get a new block if better.

How do people see the Grahams Hydra, taking @Jonners ’ point, and their power block?

What is a Consumer Unit? Is it this?

Most seem to be suggesting I try this before even considering Powerlines.

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Second picture is the Consumer Unit or Fuse box as some might say. A new Consumer Unit of about a third of the width will need to be placed close to it. I’ll put some detail together, and paste them in shortly.

You could go Hydra or Mains block from your new socket, but I wouldn’t comment as that question has been discussed, and possibly never fully resolved many times in other threads

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One other thing Nick - I’ve read that LP12’s are best off plugged directly into the wall rather than via a shared mains block. Whether that extends to PSU’s or not I don’t know but my Radikal has a socket all to itself. I’ve not compared to plugging in to my block as I’ve got spare capacity anyway but that’s yet another bit of tinkering to consider!

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Suggestion to start electrician conversation would be as follows:

Requirement for a new Dedicated Radial circuit to supply a HiFi setup

  • 10mm SWA Armoured Cable T+E (Stranded) to be run from front of house (living room), to side of house (Kitchen). May need trenching
  • Going to a double socket flush mounted (MK Logic Plus, Un-switched) - A deep wall box may help here
  • Separate Hager or MK Metal Consumer Unit with C curve 32Amp 30mA RCBO, getting power from splitting tails as they come in from the meter via Henley Block. (C curve because of toroidal transformers)
  • Earth is extremely important, so must go back to incoming house earth block from the new CU.
  • SWA Steel outer wire not to be connected at remote Socket end
  • New CU to be fed from a Henley Block off the main house input (not from the old CU)
  • Minor Works test and completion certificate

You may get asked if you want Surge Protection in your new CU. This is thought to reduce SQ, so I didn’t go for it. Of course this protection will then not be there for you, but it doesn’t look like you have it now, and it is currently optional in the regulations.

Please excuse the further information but if you don’t already know:

1- the CU pictured doesn’t look overly-old — perhaps 25-years? The good news is it’s got split-out wiring circuits and various protections. AFAIK, re-wiring of houses is normally advocated after 35/40years (with the modern cabling used).
2- the unit is probably fed from LHS (hence the on/off switch) and behind the casework (never open it up!), there are bus bars, which are metal strips which, in simple terms, carry the current etc, and which the ‘breakers’ (the things with the little test buttons) attach too. Obviously, there will be a lot of cabling in & behind the box, as the cables find their way around the house.

You should have a dedicated breaker for each material circuit in the house – usually mains ring downstairs/similarly upstairs/ditto lightning up & down/kitchen sockets/oven/perhaps boiler/immersion heater. Sadly, some sparks scribble worse than doctors and you have to manually test what’s what by turning the breaker off!!!

The breakers may have different current & trip ratings depending upon what circuit is involved – looking at the pic I think you have B-type breakers?

Nowadays a sparky also has to evaluate if you need surge protection, which is advocated to protect sensitive kit (PCs/games consoles et al) which can be busted by surges, especially when the UK could see power rationing – the powercos saw potential events coming!!

The issue with such a large CU is that with one power feed in, circuits can get the ‘noise’ and contamination from others fed from the same supply/bus bar. You could dedicate one breaker to the hi-fi supply (with a C-type breaker per @GadgetMan ) but the risks are obvious.

Per @GadgetMan 's words, it’s generally considered better to split the incoming supply from the meter via using a Henley block, with 2 x sets of tails (Live & Neutral cables), one set going to the house CU (as you have) and another to a new dedicated hi-fi CU. This should help avoiding the ‘noise’ on the house CU circuits.

As the CU box stickers advise, you should press the test buttons every 6m’s or so to check if the breakers are working OK.

The kit here isn’t expensive in relative terms.

Per @Jonners 's comments, I think why it’s advocated that an LP12 and TT PS is fed separately is to reduce the potential for ‘noise’ from the PS affecting the kit feeds (moons ago one of Linn’s boxes was ‘noisy’) and also earth loops — plus hooking up phono amps and arm leads can lead to listening to Radio Paris!

Thanks. If the new CU needs to be near the exiting one, that could be a problem because there isn’t much space of that wall. How small can this box be?

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If you just need one or two circuits then the small ‘garage type’ are fine. Here’s my separate CU for the Hi-Fi next to the house CU.

Meter box on the other side of the wall where the Henley block that splits the L&N tails and the earth block sits

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This is ours, a bit scruffier than James’s. You can clearly see the Henley block, the earth going direct to the meter, and the 10mm2 SWA at the top.

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Nick - You can see the SWA cable mentioned by @GadgetMan and @HappyListener exiting the top of Nigel’s CU.

As previously mentioned, Electricians are very good at finding routes for cabling. My CU and the lounge are on opposite sides of the house, so I have a run of about 25m of 10mm2 T&E cable that runs up to the loft via some built in bedroom wardrobes, runs across the length of the loft and then down to the lounge socket via conduit.

For the cost (just over the price of a new Power-Line) it was a no brainer and means that whatever I do with my system, I’ve done the best I can with the mains supply that’s within my control.

Note - My install was done under the 17th edition regs which meant RCD protection wasn’t required, subject to some specific installation conditions. The 18th edition regs now prohibit this for domestic installs.

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I had a dedicated mains installed last year. The electrician surface mounted the T&E in cable trunking above the skirting board, so it didn’t look too obtrusive.

Electricians are well versed in routing cables.

Since then, I’ve added another run of trunking above this for the network cables.

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Someone on Pinkfish has commented:

Unsure if you’ve possibly missed some punctuation, but SWA isn’t T& E, you would require 3 core SWA if you aren’t using the armour as your earth (cpc)

Don’t go for MK consumer unit, and ‘Fusebox’ is much better value than Hager. Don’t forget your SPD in the board.

I am completely ignorant on thus stuff, so could you comment?

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Nick,

I know you haven’t asked me for comment but your post prompted me to start thinking. I think you are in real danger here of disappearing down a rabbit hole from which you may never emerge!

There is an awful lot of hi-fi folklore involved here. Some people will claim that a certain make of consumer unit sounds superior, and that another make sounds less musical etc. etc. Likewise with the twin and earth cable. There are now special audiophile varieties - at audiophile prices!

The reality is that there is no real evidence to back up any of these assertions. Just people’s own personal experience. And how many people will have fitted say 3 or 4 different makes of CU and cable to make comparisons!

Also most electricians will regard you as either eccentric or completely insane when you explain your requirements and reasons!

By all means get a dedicated supply fitted if it appeals to you, but stick to ‘normal’ type stuff is my advice.

The T+E bit means Twin and Earth which adds up to three cores in my mind - the electrician will understand this. Whilst the outer steel sheathing is earthed (source end at least) it is not part of the earthing path for the circuit. I think the response is just splitting hairs, but feel free to change it to 10mm SWA 3 core.

SPD is the surge protection device I mentioned. I personally wouldn’t go for it, but thats a choice

“Fusebox” isn’t a name Ive heard of, or seen mentioned here before. That doesn’t mean it’s worse or better. They appear to be the same price. MK has been a well respected brand for many years, and still is, so for me it’s a safe bet. Hagar used to be the HiFi Consumer unit to go for, but I understand that they are not built as good as they used to be (someone else view - cant recall where). In the end, I think the we are talking small percentages compared with the overall gain of having a dedicated 10mm fed radial circuit. (FWIW I have no connections to any electrical brand)

Basically I agree with what @anon33182107 is saying. Sorry if it’s come across confusing, but I was hoping to make it simple for you.

Of course the nice thing about this upgrade, is that it isn’t another black box using more electricity!

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Hi Nick,

I’m with all the guys here recommending a dedicated spur. I see you have a Lingo powering your LP12 - taking that off the same ring as your Naim gear will give you a huge uplift. The LP12 sucks the life out of the sound flattening the sound stage and dulling treble.

A good power bar ie Puritan with 8 sockets will also boost your sound quality powered by a good quality cable such as Gutwire.

I’m In North London if you fancy coming over and hearing what all these things do.

Cheers Pete

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Nick - SWA = steel wired armoured cable, of which you will (ideally IMV) want the 10mm 3-core variety i.e. standard wiring set-up of Live/Neutral/Earth i.e. this is the feed which will come through the wall to the left of the kit? I would not advocate using the steel sheathing as an earthing point/effective conductor – I don’t think sparky would too.

SWA is required for external applications, especially where cabling bas to be trenched. If you were able to run some weatherproof conduit around the house above ground (per @james_n 's photo above), the sparky might/should let you run normal cable inside it – but it appears you cannot do this?

The issues are then:

1- will the sparky within regs allow you to daisy-chain another 3 x twin sockets from the primary socket (fed with the 10mm). There are sub-issues here:

a- the regs only allow so many spurs from primary circuits
b- 10mm cable is so thick & unyielding that hooking up a feed cable and then a feed (to daisy-chain) to another socket may not be physically possible. In many sockets the wiring terminals just about accept 10mm on its own.

= this is probably why using 2.5mm Twin (L&N) & Earth has been mentioned, as normal ring-wiring arrangements have 2 x 2.5mm cables in each terminal in the back of a socket, 3x if a spur has been taken off.

2- once you start breaking down the physical continuity of the cabling feeds (including using different gauge cabling), you start to compromise the project – albeit compromises are inevitable.

I know some around here have daisy-chained sockets from single feeds (I’ve never seen 8 mentioned) but the aim is for all the kit to ‘see’ the same quality of feed and, as soon as you daisy-chain, this can get compromised. The additional costs of using a 'block are recognised but this is the way I would go. And I would hook the Linn up separately in an ideal world.

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So far, I am being told that 10mm cable won’t go in standard sockets well and that 6mm SWA will be fine, and that from the meter box they would install a IP rated fusebox externally with RCBO.

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