My mains has been Marco'd!
Marco came round today with his tame sparky Matt to install a dedicated spur and consumer unit for my system (other sparkies tend to look at you as though you crawled from under a rock when you ask them to perform this particular task).
The main fuse was rather tarnished and underneath all the gunge after a bit of cleaning with Brasso it was revealed to be a 60 amp job that's probably been there since the house was built in 1971. A quick trip to HEP's Electrical Wholesale and we'd got the biggest fuse that would fit into the clips - an 80 amp Bussman. Marco and I then set about cleaning this fuse and its holder with Brasso and screenwash until they were shining like jewels.
A run of 10mm Twin and Earth was run from the mains inlet outside the back door to a board mounted on the wall just behind the system on which four unswitched MK sockets were connected to a Memera two-way Consumer Unit in a star-earth format using very short runs of 6mm T&E and 10mm earth cable.
Matt did a very tidy job that I'm confident will pass the WAF test when 'er outdoors gets home from work
The new spur arrangement is now in use and the effect it has had sonically is quite dramatic although it isn't quite finished yet. In a few days the boys will be back to bury the earth rods in the front garden in a star formation which should improve things further.
Before I describe the sonic effect in subjective terms and the anal retentive measurement freak objectivists' eyes begin to glaze over before going into scornful sneering sceptical mode, I shall give them a few measurements to consider:
Before the work was carried out
Impedance at the electricity meter: 3.5 ohms
Impedance at the switched MK sockets in use: 6 ohms
After
Impedance at the newly installed sockets: 2.3 ohms.
Note this is lower than at the electricity meter before the install. The cause of this has to lie with the uprated main fuse and the cleaning of the contacts. Obviously such nerdery makes a difference - it can be measured! What gives me a considerable amount of saisfaction is knowing that the impedance on my hi-fi dedicated mains is lower than Marco's at 3 ohms.
...And,,,, the earth rods are yet to be fitted and this should lower the impedance some more. The installation is earthed of course, in the conventional manner for the time being.
As for the sound, we tried first of all connecting the system directly to the sockets on the board bypassing the Music Works Reflex block. The first thing I noticed was that the soundstage was bigger and deeper, Ray Lamontaigne's voice had much more presence and nuance but the effect was rather hi-fi and I wasn't engaged emotionally. The bass also had an irritating bloom and was a little one-noted.
So we put the Music Works Reflex back in and connected all the components to it. This was much better - more dynamic, better timing, more tuneful and the bass tightened up nicely. The theory says this should not make an improvement as the block is only going to raise the impedance, albeit only slightly. However, this is only part of the story.
Along with electrical properties we also have to consider the mechanical effects of microphony. The speakers kick out lots of noise into the room, this vibration is absorbed by the walls and then transmitted down the power leads back into the kit. The block effectively decouples the system from this vibration and with its laminated acrylic construction in a guitar shape, it is designed specifically to do just that. It is also star-earthed so we don't lose too much of the benefit of the new installation in terms of lowering impedance.
The net result is my system sounds cleaner, the noise floor is lowered significantly allowing it to reveal even more musical informaion. The headroom is also greater. Previously the sound would begin to harden with typical CDs at around the 11 o'clock position on the volume. We are now ok to wind the wick up to one o' clock before things begin to sound a bit on the harsh side. Sorry neighbours!
The new mains installation:
Music Works Reflex Block plugged in:
The earth rods waiting to be buried in the garden:
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Originally Posted by Dave Cawley
) I still have the old one to give back to them. 
