AC 101 : Voltage Question

Different countries/continents have various AC schemes; (100v, 110v, 120v, 210v, 220v) and (50hz/60hz cps). I know voltages need to be matched between the wall and component. I've got a couple of questions. Would a component from overseas that uses 210-240v work on an American 240v circut? Does it matter if the circut has one or two hot legs? Does equipment on 240v circuts sound inherently better because the power is being delivered "balanced"? Is 240v power "balanced"? Is the higher voltage used overseas delivered one one leg? Just a few thoughts.....
European voltage is at 50Hz,the U.S. is 60Hz.Equipment that operates on 240v sounds no better or worse.
Different schools of thought, that's all. Euro goes with higher voltage & lower current with lower frequency. thus can use smaller cables to carry the power line and supposedly it will provide for less maintainence.

We go with higher current and lower voltage with a higher freq.

Both alternate current, one leg hot one neutral, one comon.

Six one way, half a dozen the other. Diesel or gas... you pick. It all gets us where we want to go. Each will have it's own native benefits and/or drawbacks.

There are devices which will allow operation of the predisposed gear in either camp 240v/50Hz or 120v/60Hz. Some equip makers refrain from converting these items to or from in after the fact scenarios. Some have no problems with it... going on the info I've read in these threads here.

I suspect that's also why some items being made today will automatically seek out and run on the wall supply, regardless the sort being supplied. Oppo... BenQ.. etc.
I have my space wired for both 120 and 240, comes in handy sometimes.

The 60 Hz USA standard is easier on 50 Hz power supplies so equipment set up for Europe works fine in the USA, provided you get the 240 V right.

All that being said, I've had three or four pieces of equipment, including both amps and preamps that were wired for 120 and then to 240 to see if I could get an improvement. Even with the best AC outlets and top quality power cords, the difference is pretty much zero performance wise and I did not notice any change in billing from my electrical provider either.

I still don't regret having the 240V option, just in case I get a chance to hear a piece of Euro gear that has no easy way to switch to 120 V.

A lot of people don't realize that our homes are wired with 240 and split off to 120. The 240 is only distributed to things like an electric oven, hot water heater or clothes dryer, but it's easy to pull a run into a listening room.

I have a strong opinion about outlets. If you wire your listening room for 240 I advise NOT using a 120 volt outlet. It will work since your asking it to handle half the current but sooner or later you or someone else will forget that it's 240 and not 120 and your vacuum cleaner (or whatever you plug in) will work great for about a second and then follow with a puff of smoke. Don't do it.