Re: Mesa Boogie Import Europe
The models intended for export to countries with 230V power have a different power transformer that's wound correctly to work with 230V power. The rest of the power supply circuit is the same except bias portion (two resistors), at least in the old 2 channel models. In theory, it should be a fairly simple mod: Disconnect and remove the US spec power transformer, install and connect the EU spec transformer, and change the bias resistors. In reality, you'd also want to have a schematic on hand so as to avoid surprises when doing the mod. If you're not comfortable making such a change yourself, you'd want to enlist the help of an technician as well.
However, while it may be a simple mod on paper, it isn't going to be an especially cheap one. The power transformer is going to be one of the most expensive parts in the amp. It's also a heavy beast. When you total up the price that Mesa's going to want for the part, the cost of shipping, import duties, taxes, labor fees from the technician etc, it may very well be less expensive to buy a step-down transformer that will take 230V from the wall and convert it to 117 that the amp can run on.
My recommendation is to simply buy a step-down transformer, and use that instead. Just be sure the step-down transformer is rated for the current that the amp will draw, which is at least 4A at 117V, not 1A, per the schematic. 1A at 117V is 117W. The Dual is rated to put out 100W of power. 100W of output power from the amp will require *more* than 100W of input power from the wall, due to the inefficient nature of vacuum tubes.
