Most amplifiers/preamps/equipment is designed for 50/60 hz. I have a 240V European amplifier that runs great on US 240V 60hz power. IIRC, 60 hz is acttually a little easier on the transformers that 50hz.
You would have 2 options: 1. Just install a 240V outlet, like you would for a dryer, welder, or any other high current appliance. that is what I did. 2. buy a step up (not down) transformer. Tripp lite is a good brand. buying the cheap ones off ebay just provides your high end equipment with poor power. expect to spend $500 or more. Oversize it some, although this isn't as important for a pre as it is for an amp.
I assume you've already investigated whther the amp is switchable or rewirable to 120V. some are.
Jerry
