Can US 220v be used to power foreign 220v pieces?

So long as the gear can accept both 50 and 60 Hz frequency, yes (most modern gear can do this). However, most 220 VAC 60 Hz in a residence is used to power the stove and electric clothes dryer (furnaces too, but that's rare). Those can be noisy, so you could have an issue if running audio and appliances at the same time.

Good luck & happy listening!

Do it all the time, have no issues with it.

Good listening

Peter

As long as the unit does not have a synchronous AC motor, that
locks onto frequency, for it's speed control(ie: some
turntables, tapedecks, CD players).

I googled the above with no sufficient answer for audiophilic equipment. Anyone here with experience using a domestic 220v line to power an overseas sourced 220v piece? If so were the results sonically successful ( no humming, etc) and were there any equipment malfunctions?

Mojoetoo,

Things you should consider before making the purchase.

1) Usually audio equipment can withstand mains voltages that are within + or – 10%. If the equipment you are interested in is designed for 220V then the maximum safe operating over voltage would be 220 x 10% = 242V. Today most residential houses in the US mains power is around 120/240V nominal. Some higher, some lower. Example My mains voltage averages 120V to 122V / 240V to 244V respectively.

2) Whether the audio equipment is designed to operate on 120V or 220V the equipment is designed to be fed from an AC Grounded power source that has a Hot, ungrounded conductor, and a neutral, grounded conductor. (Neutral is at ground potential.) Equipment protection fusing is in series with the Hot Line conductor only. In the case of US power, 120/240V, both Lines, legs, of the 240V are both Hot conductors. So in the case where the 220V audio equipment is connected to US 240V mains only one Hot Line is fuse protected inside the equipment.

3) If you have a 15 or 20 amp 240V branch circuit installed you will not be able to use a standard NEMA 5-15R or 5-20R 125V receptacle. You will have to use a NEMA rated 250V receptacle. Problem? Ya, you will not be able to use aftermarket power cords with US NEMA standards 125V 5-15P amp plugs. You will have to cut off the plugs and install a NEMA standard 250V plug on the cord. Or you will just have to build your own power cords.

4) Last but not least…… You may have trouble finding a licensed electrician that will install the 250V branch circuit for you.

NEC 2011
Article 210.6 (A)
Occupancy Limitation. In dwelling units, and similar occupancies, the voltage shall not exceed 120 volts, nominal, between conductors that supply,

(2) Cord-and-plug loads 1440 Va, nominal, or less or less than 1/4 HP.
.

Thanks all. In summary sounds doable but with significant caveats as Jea48 so thoroughly outlined. Those who have run US220/240v into foreign sourced components did any noise, circuit damage, or safety issues arise that were felt to be related to foregoing conversion to 110v? Further if one decides to convert a 220 component to 110 are there sonic penalties to be expected?

I'm not an electrician; I have heard any 120 volt duplex outlet can be adapted to provide ~ 240 volts by strapping the 2 x 120 outlets together to provide 1 x 240 outlet. Search it here or google it. Then use an isolation transformer--the best are balanced--to give clean ac.

I run two dedicated 10 gauge 240V lines for my German-made Symphonic Line Kraft 250 monos. Voltage at the outlet runs between 239V and 243V. The lines are attached to 30 amp breakers in the breaker box. I actually had the amps converted back to 240V from the 120V they were imported at. I have subsequently been told by the leading SL tech in this country that the conversion back to 240V was best for the amps at startup, as feeding them 240V current would assure smoother startup. So far I have had no issues whatsoever.

The 30 amp breakers each take up two 120V slots in the breaker box. Perhaps this is what Ptss is referring to? I'd certainly consult an electrician before attempting any DIY work at the outlet box to create 240V service using typical 15 or 20 amp breakers and 12 gauge electrical wire that is used in normal 120V operation. That does not sound like it would meet code requirements for 240V service.

Why not use a step-up transformer? They can be had for cheap on Amazon and work really well. I am using a 1500 watt one for two German made Octave MRE 130 tube amps.

Audioquest4life