Last time this issue came up, it was an Aussie guy who was bringing a rather large system to the US. His matching transformer weighed about fifty pounds.
And was I confusing Aussie voltage with Japanese voltage? Somehow I remember his conversion as being from our 120V to 100 volts. I could be wrong.
A good answer is easier with a clear question giving the make and model of everything. "The biggest problem in communication is the illusion that it has taken place." -- G. “Bernie” Shaw