I just completed a replacement of my service entrance of the house which had a rather typical 200 amp breaker box with around 60 breakers all GE equipment. The main lines coming in from the meter outside were also typical heavy gauge aluminum and the main buss on the breaker box was aluminum. The reason for the change out was that I had been having a lot of peculiar problems with my new sound system; specifically my amps would go into over heating shut down or turning off due to lack of current under heavy loading (I do tend to play it loud in a 10,000 cubic foot room). I had been using a nice Parasound amp driving a pair of Bryston Model T's, but I thought that I needed more, so I picked up a pair of Anthem Statement M1 monoblocks which are rated at 2000 watts per channel at 4 ohms if driven by dedicated 240 volt mains, which I am doing. Even the M1's would go into protection occasionally when pushed, but not what I would call excessive pushing.
I was begging to think that I had something else going on as the house took a lightning hit which came in via the power service two years ago. I called a friend of mine who is a retired EE with Bell Labs/Lucent and formerly the US Coast Guard. This guy knows more than anyone I know about electronics. I asked him if a slight voltage drop under loading could be causing my issues. I wanted to try removing the breakers, cycling them after a hit of DeOxit 5 and a light spray to the contacts which clamp the buss. He said I was reading his mind; he felt I had a slightly high resistance issue on one or both of my lines which is causing a voltage drop when under heavy loading and that is why the amps go into protection mode. He asked me how the buss appeared in the panel and I said the aluminum was either silver plated or had a slight aluminum oxidation as is usual, but I doubt it's silver plated, so it has to be oxidation. He said "get that panel replaced! In fact get all the aluminum out, including all the main feeds from the meter" "you need to have it all changed out with copper only" Dave told me that more house fires have been caused by aluminum service entrances than anything else as the aluminum oxidizes or isn't installed properly with a proper coating of NoALOX; it all leads to elevated resistance with time and it heats up. Especially when the house is near the ocean, which I am.
So, out it all came; I had all new Siemens copper buss panels installed with Siemens breakers and new heavy 200 amp rated copper mains brought in through conduit to the panel.
Was there any noticeable differences? You bet there is! I find that I get much more output from the amps at much lower volume settings and I cannot push the volume as high as I used to or it's blistering to the ears.... plus, when I opened all the doors to the deck and really pushed it so that I could go outside, the amps have not gone into protection mode! Wow, first time. And I took temperature readings last night on the heat sinks of the M1's after hours of heavy use, they were reading around 90 degrees F on a very hot summer night. I mean they were about 5 degrees warmer than the ambient temperatures. This is approximately 10 to 15% cooler than before.
Now 'hear' is the best part: I could not believe how much dynamic range I am hearing. The upper mid range and upper range is far more present than before, far more detailed and the bass is faster, tighter and more powerful. I am amazed and when I reported this to my friend Dave, he said that of course I am going to hear this improvement as the amps are not seeing voltage sag under load, they are getting full delivery of current and when high demand for current with dynamic music occurs, they are delivering much more.
The best way to describe this is that it's as if the power from the amps has doubled or more and the detail in the music is as if I just installed a $10K cartridge picking out things I have never heard.
Total cost for the change out by the electrician, $2600..... far less than buying a fancy new phono preamp and cartridge :) I cannot over emphasize the importance of using only copper mains and buss in the service entrance. Aluminum seems to very common in construction as it's less expensive and builders use it often. So if you are into great HiFi as we all are; inspect your service entrance!!