If a device has a power supply that will automatically switch between input voltages, like a laptop computer and most other electronic devices these days, it will have what is known as a switching power supply. These supplies also have the benefit of being lighter, smaller and more efficient than linear power supplies (that are used in most tube guitar amps).
One parameter taken into consideration with a switching power supply is called hold up time, which is basically how long a supply can output its rated voltage when the input power is removed. I'd suspect that the designers of the Kemper paid close attention to the supply design so that it would continue to operate for a short period if the input power is removed, as this would help tremendously with reliable operation with the flaky power you often see on stages (especially outdoors powered by generators). These power cutouts can be under a second, but some products will lock up and stop working with such issues.
Many digital products will freak out when they are powered by generators, as they may not be able to handle the unstable voltages and intermittent cutouts. Analog amps and effects often work much better in such situations as their supplies by design hold a reservoir of power that will smooth out the variations. It is very gratifying to hear that the Kemper has a supply that will work under intermittent power cutoffs and brownouts.
Great points, MKB.
