Dedicated Power Lines

Ptss,

I assume that was done before the three new separately derived grounded AC power systems were put into service.

*Check unloaded voltage.
*Check Hot to ground to verify the neutral is grounded.
*Check for AC polarity at load receptacles.
*Connect load/s and check voltage again.

The test I suggested, in my post of 06-14-13, is to find if the three xfmrs outputs are in phase or out of phase with one another.

The same test used to make sure multiple dedicated branch circuits are fed from the same Line, leg, from the electrical panel.
An accepted norm where audio equipment is connected together by ICs.
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Split Single Phase electrical service is most commonly found in residences and smaller commercial buildings,
and is commonly used to feed AV equipment. One key advantage that single phase has over three phase
is that while harmonic currents are still present, it is not possible for the “triplen” components to add in the
neutral. In addition, use of split single phase can result in at least a 6dB reduction in noise floor as compared
to three phase if the capacitances of the connected equipment are relatively well balanced. However, any
leakage currents on the safety ground wires of split single phase load circuits fed by different phase legs will
add together due to the 240V potential difference.

http://www.exactpower.com/elite/assets/pdfs/theTRUTH.pdf
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Jim

Jea. Can't imagine what you are on about bringing 3 phase power into this. Hmm. I believe most people are going to install their 'power systems?' correctly, regardless of the type of conditioning they will use. Just an assumption.

I think if I understand it, if you use both phases of power at home then if you cross the hots you can produce 240volts. I would think anybody who uses 220 power conditioning is subject to this and anybody who uses multiple plugs from different phases are all in the same boat.
You are advocating only using one phase for stereo use.

I have a 55 year old house with an original 100 amp service which, in a way, worked in my favor because I was forced to upgrade. I did this approx 15 years ago with the addition of a 200 amp box bypassing the old one to serve 220V users such as the clothes dryer, stove and A/C air handler. The 100W box was otherwise left unchanged feeding all other existing circuits in the house. This was a matter of convenience because the 100 amp box is in the garage.

Modifications that were made to serve the sound system were done primarily to protect it, to the extent possible, from potential damage from power feed glitches. I didn't consider it from the standpoint of maximizing sonic quality and it still wouldn't be a priority in my thinking today. Anyway, the modification consisted of a lightning arrestor with surge protection and separate 30 amp breakers from the 200 amp panel serving two outlets on the wall which serves the system. I also use a line conditioner for most of the components in the system. I'm sure that there are some purists that would cringe at all these intervening electronics and several have already reminded me that this protection may provide some peace of mind but is mostly not that effective.

From a purely sonics standpoint, and I'm still not convinced that this is an important issue, I may have gained something by accident. The electrician did use 10 gauge Romex from a roll on his truck and the run of these two wires was relatively short (approx 25ft). They were run in the garage attic, parallel to one another with no crossing of other conductors, and the installation in question was far removed from "noisy" installations such as the central air handler by about 60'.

I don't think I added much to the conversation except to remind those who are doing upgrades to their house power, that it's a good idea and pretty simple, to make accommodations for your sound system at the same time.

I also live in an old house and upgraded my service. I had my service upgraded to a 250 amp service with new breaker box and what I think helped the most is changing to new 0/0 wire from the pole to the new breaker box. The new feed to the house is a much larger wire.