Title: Re: Flick's Chariot
Post by JBbuzz on 02/24/20 at 00:27:48
Growing up in an era when tube electronics were rapidly being replaced with transistors, unused tube radios/stereos/tvs were handed to us inquisitive kids. Most of the equipment had seen better days and did not work. Actually, I am surprised my life did not end with electrocution as many times my hands where in the box, power on, trying to wiggle the right tube to make the thing work again. I did learn some good life saving respect for electricity when one of my adventures abruptly sent me across the room with my back hitting the opposing wall then sliding down to the ground on my arse! Dazed and confused, it was about that time the thought of making a table saw came to mind.
Anyhow, there was this one working radio we kept up in my cousin’s room that had an aux input we used to play 8 track tapes. The radio worked OK, but on one of our overnight tinkering sessions the FM radio seemed to become haunted with holographic music. We looked at each other in amazement and listened intently until falling asleep. We were totally disappointed the next morning when the FM just sounded OK again.
The quest began to find out why. Well it seemed to be a couple factors. A perfect FM signal being fed and amplified using clean AC. The airways were clear of electrical interference as well as the AC grid power during the wee hours of night.
Building the Chariot, it was one of my goals to supply the electronics with clean AC power within budget. Searching the internet produced an article written by Magnan Audio Cables, “Recommended Audio System Tweaks”. The suggestions presented seem reasonable and within means. Basically the filtering tweaks adding film caps between hot to neutral and another with neutral to ground all over the house to eliminate the grunge in AC supply. I did not like the idea of adding custom built modules to outlets as described in the tweak but believed running a home run power source to the Chariot’s audio equipment and adding the hot to neutral treatment to that circuit could be just as effective. The neutral to ground receptacle modules could be eliminated by adding the capacitors to different circuits at the breaker panel. 320uf of capacitance was added to the Chariots audio feed and 6 separate circuits were treated at the breaker panel. When complete there was a noticeable improvement with soundstage presentation and more detail (blackness). That was almost twenty years ago!
Along with my respect for electricity, I pursued a couple years of training in electronics and held jobs that required said training. Over the years troubleshooting, there has always been this nagging wonder of why neutral to ground voltages were present and the same always fluctuating. Well there are many reasons and surely many of you engineers can fill a book of causes. But the fact is it’s there, can not be eliminated, and causes inaudible/audible effects with sound reproduction. This led to the next tweak for the Chariot – Balanced Power. I used Jon M. Risch recommendations for balanced power. At a risk of speaking out my league this is what I know:
Using the center tap of a balanced AC transformer the tap reference is effectively at 0 volts; 60 volts on the sine wave upswing and 60 volts on the down swing. Connect the grounds of equipment to this reference point makes all the equipment ground at 0 volts eliminating ground loop cause of stray voltages. Connect this 0 point reference to earth ground shunts grunge lowering the noise floor.
These tweaks along with a new ground rod were added and silently served well over the years, I think! Often over the years, I wondered if that box next to my circuit breaker box was still doing its duty! Quite frankly, I forgot exactly what it did until now. More on that later.
Neutral to ground box with cover removed.
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