Voltage question?

I would like to ask if I buy an Audio Research amp of 120V or 220volts and use it in Australia which uses 240V. Is it easy to change to the desired voltage or would it be a big and expansive job?
Thank you
I suggest you contact Dallas Clarke of Clarke Audio in Melbourne. He does a lot of this stuff and will be able to tell you how much it would cost. He is a very highly regarded technician. Hope this helps.

Thanks Phaser,
May be I rephrases the Question. I would like to know if Audio Research's amp has switches which change voltage from 110 - 240V something like that. I am talking about pre-amps and power amps like ref.2 or vt100 or 200.
NO they don't. I technician should be able to change the voltage to 240vlts on the pre amp.
NOt sure on the power, but I doubt it - it generally has a special 240vlt transformer for power amps.