Dedicated Mains - Some Pictures
Posted by: DaveBk on 21 February 2009
In recent months there has been quite alot of interest in dedicated hifi mains circuits. Many people have asked what is involved so I thought I would post a few pictures to explain what I have done:
This shows the new hifi consumer unit. It's fed directly from the incoming mains using 25mm power conductors and a 16mm earth. Two 32 Amp circuit breakers feed the 6mm and 10mm radials.
This shows the 2 radial circuits crossing the loft before heading down the wall buried in the plaster.
And this shows the final socket outlets on the wall. The switched one is a spur off the upstairs ring that is used for the Sky box and DVD player. Next is an unswitched double where the 6mm radial terminates - this powers the NAP300 in my case. Next to this is the 10mm radial again terminated with a MK unswitched socket powering the Supercap for the NAC252 and the Transporter. The Transporter is modified to replace its switched power supply for the digital side with a linear unit of my own design so no nasty RF gets back onto the radial.
Finally an picture showing one of the measurable benefits of dedicated radials. The meter is an earth loop tester - it measures the resistance of the whole circuit from the local substation to the socket via the live and back to the earth. (Earth and Neutral are usually joined in the cut-out where the mains enters your house) Generally speaking the lower the resistance the better. The meters are shown in the same order as the sockets so it can be seen that the 10mm radial has the lowest earth resistance - low resistance return paths to earth are important in my experiance with high end hifi.
The only place in my setup where the mains earth is connected to signal earth in in the Transporter, this should be connected to the 'stiffest' earth so I use the 10mm radial. I also power the Supercap from here to keep it away from the 300PS.
So this wraps it up, not forgetting of course the 3 Powerlines from the sockets to the kit.
This shows the new hifi consumer unit. It's fed directly from the incoming mains using 25mm power conductors and a 16mm earth. Two 32 Amp circuit breakers feed the 6mm and 10mm radials.
This shows the 2 radial circuits crossing the loft before heading down the wall buried in the plaster.
And this shows the final socket outlets on the wall. The switched one is a spur off the upstairs ring that is used for the Sky box and DVD player. Next is an unswitched double where the 6mm radial terminates - this powers the NAP300 in my case. Next to this is the 10mm radial again terminated with a MK unswitched socket powering the Supercap for the NAC252 and the Transporter. The Transporter is modified to replace its switched power supply for the digital side with a linear unit of my own design so no nasty RF gets back onto the radial.
Finally an picture showing one of the measurable benefits of dedicated radials. The meter is an earth loop tester - it measures the resistance of the whole circuit from the local substation to the socket via the live and back to the earth. (Earth and Neutral are usually joined in the cut-out where the mains enters your house) Generally speaking the lower the resistance the better. The meters are shown in the same order as the sockets so it can be seen that the 10mm radial has the lowest earth resistance - low resistance return paths to earth are important in my experiance with high end hifi.
The only place in my setup where the mains earth is connected to signal earth in in the Transporter, this should be connected to the 'stiffest' earth so I use the 10mm radial. I also power the Supercap from here to keep it away from the 300PS.
So this wraps it up, not forgetting of course the 3 Powerlines from the sockets to the kit.