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Lowering House Grounding Impedance

So, I’ve finally gotten to a place where I’m pretty happy with the pieces of gear in my system. I know, I’m surprised too. Recently, however, I read about lowering the impedance to ground as a potential improvement and thought I’d give it a try. I’ve done quite a bit of tweaking to get to where I’m finally happy but I had never really looked at the grounding situation for my house, other than to make sure the utility panel was tidy and connected up right. In reviewing my house’s grounding to earth situation, I found that it didn’t have one! My house was built more than 50 years ago and they relied on grounding to the cold water pipes. This was fine while there was 100 feet of 3 inch copper pipe running to my well but when we replaced that pipe with plastic my grounding was gone. Initially, I drove two 8 foot copper clad grounding rods and bonded them together and grounded the external utility panel to them. I was really surprised that the difference the good grounding made to my system, it really removed a layer of haze that I didn’t know was there. Like cleaning a window that is already fairly clean, just added clarity. As I understand it, the lowering of the ground potential is what is responsible for the increase in sound quality. Has, anyone else experimented with improving their ground situation? 
hollandw

Showing 3 responses by hollandw

hollandw OP
16 posts
 
It needs to be said that my grounding exceeds code requirements with everything bonded together and hooked up by a licensed electrician. I bought the materials and drove the rods but I let a licensed professional do the final hookup so I have a receipt. I vehemently concur with all here that there can only be one grounding path, with all rods properly bonded together! I started my journey to a lower grounding potential while looking at some of the Nordost products, one of which advocates an additional ground! They do have a caveat in their literature but I can’t immagine what would happen if a close by lightning strike tried to equalize its potential through my house to the other ground. I’m no engineer but I’m going to bet you would be lucky if it just wrecked your gear and didn’t burn the house down. Moreover, I’m sure the insurance adjuster would be happy to find that he could avoid paying out due to a not to code grounding solution.
hollandw OP
16 posts
 
An aftermarket power cord, higher grade wall receptacle, or fuse built for audio purposes shouldn’t be doing anything either - but they do. I don’t understand it either but I can tell you that I listened, went and did the work to effect a good low impedance ground, then listened again and heard a difference. Without telling her what to listen for, I asked my wife if she heard anything different and she identified the same “removal of haze” as I had heard and I’m pretty sure I’ve never even used that terminology around her.
hollandw OP
16 posts
 
There are so many things that inexplicably affect the sound of hi-end audio it can just about drive you nuts. The good low impedance earth grounding I established for my house made a positive difference we could easily discern. But of course that wasn’t good enough, I had to screw with it to see if I could make it even better. And, of course, I screwed it up and had work to get back to where I was before. 
I had a good ground established, with two 16’ foot rods bonded together, connected with 4 gauge stranded copper, clamped to the rods. I’d heard that solid core could be better, so I bought 25’ of solid core and some exothermic single weld cadweld devices (these things are pretty cool, they use a pyrotechnic material to form a welded bond inside a crucible between the rod and wire). I added the wire on top of the stranded, in parallel. End result was that the benefits I’d realized disappeared! I’m guessing some sort affect occurred due to the bare wires touching each other before the rods, or running parallel, or both. So, I ended up gambling and leaving the solid core and ripping up the stranded. The end result is that I think I’m back to about 98% of where I was. The main impact has been to bass and, in careful listening, I think I’m still just a tad light on the lower bass from where I was after my initial installation of the low impedance earth grounding. I’m going to try a couple more things and then just buy some more 4 gauge stranded and put it back the way it was if I’m still not happy. Don’t you love this hobby? 
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