AmpliPi ships preconfigured for 120V mains power, but can be switched over to work on 230V mains. Internally, there is a red switch on the side of the Meanwell power supply that can be toggled for 230V. The easiest way to get at this witch is to take off the top cover. The power supply switch can potentially be accessed through the vent slots on the right side of the unit as well. Here are some pictures to help clarify the process:
WARNING: You MUST set the internal power supply switch to 230V before connecting AmpliPi to 230V mains power or else you WILL release the magic smoke and damage the unit.