I was re-reading Russ Andrews' article on the mains supply a few weeks ago (you can find it here. There was a downloadable pdf version, but I couldn’t find it on the website now), it gave a wealth of good advice on improving the electricity supply to our hifi system, while, of course, pushing for some of his products.

What I found good was that the article was largely devoid of out-of-this-world claims, hyperboles, mysteries etc.. Someone like me, who fortunately still remembered some high school physics, could understand most of what he said perfectly well. :-)

A section drew my attention particularly: it was under chapter 11: “high impedance > mains cabling and mains circuit”, in which he compared the merits between a radial (spur) circuit and a ring circuit. He had this to say: “The advantage of a ring circuit is that looping the wire back to the consumer unit doubles the current handling capacity of the cable by halving the impedance. The wire in a radial circuit must be much larger if it is to match the lower impedance of a ring circuit.” That made sense. He went on to say that some who have installed spur circuits, which looked good on paper, have suffered sound quality degradation.

Diagram courtesy of Russ Andrews' website.

My current power supply to my hifi equipment was a spur circuit setup - 2 separate power sockets wired independently and directly from the fuse box (on the same phase (coming out from the same circuit breaker in fact) of the 3-phase power supply). Since the sockets were installed side-by-side in my room, I could easily convert them into a ring circuit, by connecting the two sockets to each other in the wall with short runs of wires - earth to earth, neutral to neutral, live to live.

I decided to try this last Sunday afternoon. In the process I also discovered that the earth cable to the socket was a little loose, which I tightened up (Russ Andrews also advised on the importance of good earthing). For good measure, I also put a few squirts of contact cleaner on every bare wire end and the socket terminals.

And what did I get out of one Sunday afternoon’s worth of work without spending money?

I measured the voltage from the sockets, 246v – normal voltage to my house. I switched on my system component one by one, all lights came on, no problem, a good sign. I pressed ‘play’ on my remote, expecting to hear something good, but there was simply utter silence for 3-4 seconds. I started to curse under my breath, thinking that I had to spend some more time rechecking all the power cords, interconnects and speaker cables. Then the next moment, the musicians just appeared and lit up the room. Wow. The system was working alright; the background was just much darker than before, much darker indeed. Apparently, I was so used to unconsciously hearing a very faint haze from my system, I did not know it until it was gone. More recorded details emerged from this blackness. Images were slightly more 3-dimensional. Bass and treble also improved with better definition. The decay of notes were clearer and more assured.

Any downside? I detected an occasional glare in the upper mid. Why? I don’t know. Will it go away? I hope so. It reduced after 2 days, let’s see after a few more days’ playing time.

This is absolutely the most cost-effective ‘upgrade’ to my system, equivalent to switching from a stock powercord to a very good aftermarket one, but all without burning any hole in the pocket.

My additional 2 cents: if you install a ring circuit, you'd probably want to limit the number of power sockets on the ring. I think every cut/break in the power cable may also increase the impedance to the current flow. I think it'd also be a good practice to dedicate a circuit to the hifi system without mixing it with other household equipment.

Disclaimer: Electricity can kill. Please get professional help if you intend to do any electrical work. This writer is not responsible for any mishap.


P.S. 28th October - The occasional glare in the upper mid was finally gone. The clarity in the sound and the quietness in the background remained.

3 comments:

lio said...

good link and good observation

maggielurva 愛美姬 said...

i have been wanting to invite a prominent guest to my house to listen to the stage 3 but the AC has been so bad for the past 2 days that i have to keep postponing the appointment.

i guess every system suffers from TNB's poor supply, it is a matter of degree and whether the system is transparent and revealing enough to tell the damage.

this country's AC sucks ass big time :-(

Zimmermannn said...

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