plz help ?? voltage converter

Yes you can, but make sure that the converter is rated significantly higher in watts/amps than the receiver and sub. It will also adversely affect the sound if the equipment is power starved, so I would go with 1000 watts converters for each (Sub and Receiver), which run you about $80 each. I doubt that a $40 converter will do it for you. Good luck,
Arni

Arni is right, do as he says. Cheers,

Make sure the converter contains a cycloconverter so that you get the proper 60Hz signal overseas too! Arthur

Aball's last suggestion in my opinion is only important with certain TT motors or other analog devices which are clocked to 60 hz. Otherwise it does not really matter if you drive your amps or preamps at 50/60 or even more and variable cycles, as is applied in the PS Audio Powerplants for example.