Radial circuit wall sockets!

You can get a single 10mm cable in a standard socket. You would need a radial for each socket. A socket will accommodate 2 X 6mm cables though. 

I employed an electrician. 

Always the best idea! 

Thanks FINKFAN. So thats how it's done. 6mm might suffice then. Just out of curiosity anyone gone from 6mm up 10mm and did it have much impact on what you were hearing?

We have a 10mm cable to an unswitched double socket, which is fine for us as the stereo has only two plugs, so we can use powerlines. While 10mm is better than 6mm, I wouldn't expect the difference to be earth shattering. The other important thing is to ensure that you have a separate consumer unit with 50amp breakers and that the earth goes straight to the meter board and doesn't piggy back off the main consumer unit. Make sure also that there are no joins in the cable between the consumer unit and the socket. 

+1 HH

im having 10mm radials installed in my new office. Luckily they'll only be 3m from the dedicated board

This is exactly why I posted. There is an incredible wealth of knowledge on here. I will of course employ an electrician but the more specific I can be of my requirements the better I think. I am anticipating a level of bemusement initially  to be honest.

I had a 2.5mm radial, which was no better than connecting to the ring circuit. I installed multiple 6mm radials and the improvement was huge. I was really pleased with the system but a friend had 10mm installed a few weeks later. I couldn't believe the jump again in performance, so much so that I bought a drum of 10mm on the way home and over the next couple of days installed it. 

I left the 6mm in for the tv, dvd, etc, and yes it really improved these too. A few weeks later I retried the hifi through the 6mm. Within a few mins it was put back on 10mm where it has stayed ever since.

Go for 10mm multiple radials if at all possible. Also there are many other points to consider, such as the consumer unit, main incomming service fuse, earthing, sockets, burn in, etc.

Go for it, you'll never look back.

The Mk unswitched sockets I have would not need upgrading but when we talk about consumer units are some better for our purpose than others?

Yes they are. When I installed mine a few years ago I tried a couple. The best was the memera ad2000 range. The difference was really unexpected but a good lift none the less.

We have a Memera too. I believe they have been taken over by Eaton.