The thicker the cable the less resistance and less voltage drop over a long run. Though with 10m there will be negligable if any drop.
Mains cables running parallel usually isn’t a problem but if someone in the house uses those ethernet over mains adapters they will carry noise. So if you could run the hifi mains 10cm apart that would be great. But I’ve not bothered.
More critical is the earth line. Insist on it being dedicated to the circuit all the way to the consumer unit. If you can install a dedicated earth for it even better. That is something I have done.
Finally, before you go for 10mm cable, ensure your sockets support that. For example, Furutech sockets will go up to 8.2mm.
I don’t see a problem with that. Installing a fully separate earth is not always easy. Splitting it before the CU is the next best and I’d be happy with that.
Separate earth rods are quite normal where I am (not UK) as regs here require certain types of appliance (gas boiler, solar panels etc.) to have their own rod. If your electrician say a dedicated earth is difficult/expensive, don’t worry about it.
There is a similar thread running already. If you contact @Richard.Dane he could merge them.
I have just had Solar PV, batteries and a Zappi EV charger installed. They didn’t want to touch my existing Distribution Boards so they added a new one with 9 spare ways meeting UK 18th edition March 2022 with mandatory Surge Protection Device. They had to bring an earth cable from the meter cupboard which was difficult. I already had the Henley block. In the process they added a pull cord and a new unconnected earth so that when I tidy up my two old DBs both have a dedicated earth back to the PME in the meter cupboard. They also had to get data and power to the meter cupboard for CT clamps and the SolarEdge PV control box.
I will soon migrate 9 circuits to the new DB off the old DBs which have my Hifi radials. I will probably add an additional DB sharing the mains with the new DB so that my old DBs end up with just the Hifi radials. An unusual way of getting the Hifi on to a dedicated DB as per the diagram already posted above!
Not sure if you are in the UK, but if you are you would be advised to carefully consider all future needs. You will have to ensure that anything enhanced is brought up to the latest regs.
Definitely split the incoming feed and run a separate line to a dedicated CU. Dedicated earth is then more straightforward. Sparks may push you towards using a spare slot on the existing CU which kind of defeats the object. My supply is as independent of the rest of the house as possible. It was a great upgrade for very little cost…around 350 from memory.
I think your diagram looks correct to me, except that Naim recommended to me that I should use only one 10mm cable from the dedicated CU to the HiFi.
This may mean that you only have one double socket, but a hydra or a quality mains block would provide connections for multiple boxes and maintain star earthing.
That’s how I have mine configured with just a single radial. I have all the sockets I need.
I posted the diagram originally with the three radials as others were asking how they could add additional radials. It may be useful for some to have additional radials, especially if you want to keep kit such as Linn sources with switch mode supplies away from the Naim kit.
@richardjpaterson The diagram’s just a visual guide of the Naim approach to be able to show to a prospective electrician. Regulations get updated and individual installations may require specific changes, so your electrician is best qualified here to install a safe and certified setup.
I had a 2.5mm2 and 4mm2 radial put in several years ago when we had work done to the house. I actually prefer the 2.5mm2 in terms of musical enjoyment. However, I don’t use either cos the standard house wiring is more engaging - it doesn’t do the Hi-Fi stuff nearly as well but is much easier to just get on and enjoy the music. I go back to it every few years but quickly reach the same conclusion. Always wondered if this is because the new radials are running in the wrong direction, but I’ll never know for sure since there are so many variables.
This pretty much matches my setup, only difference is that my earth from the CU went straight back to the earth block thats attached to the side of the incoming mains cable, so no additional block was needed.
My run to the single unswitched socket was about 40 meters, also using 10mm cable.
Multiple radials certainly make things easier when it comes to connecting more than one socket. When Steve Hoskins was at Naim I asked him for recommendations, and he was very specific about a single radial being better, so I just went with his advice.
Now have the dedicated HiFi radials on their own in our old Distribution Board having had all the other circuits moved to the New Distribution Boards. I have a CT clamp monitor on the Hifi reading 100W.
The TV through nDAC spdif sounds good. I must admit Celestial Echos by Malia is sounding out of this world! Heaven only knows what another 10 days of coming on song will deliver! Fundamentally, no new electrical kit but HiFi now on its own.
The photo shows the power to the 16 circuits being monitored by the Emporia Vue Energy Monitor. The percentages are crap because we have Solar and Batteries. The Inverter is the main source. Hopefully it will show the overnight charging of the batteries.
The electrician tested everything before moving the circuits. A few cables needed extending to reach the new DBs. The earthing originates from a block in the meter cupboard, which has the PME, earth rod and bonding with each DB earthed from this block in the cupboard. Should now be as recommended on this forum. We have surge protection on the new DBs, but not on the Hifi.