The benefit of using 'wall wart' power supplies is that Yamaha and other instrument
manufacturer's dont need to make equipment with different power rating tranformers
inside the instruments to cover the worlds differing voltages. If you move to another part of world with a different voltage your instruments with internal power supplies would all need to be changed, the ones with external transformers have a much more simple solution so try and grow to love the wall wart, it may be of benefit one day.

larigot