Power spikes and surges can definitely do a number on audio equipment — happens every day. Power Conditioners and Filters can make sure it doesn't happen to you. It constantly monitors incoming AC, and if it detects a significant overvoltage condition, it automatically shuts off power to all connected equipment. In the case of a sudden voltage spike, many surge suppressors are designed to "take a bullet" and sacrifice internal parts to save your gear. It's a noble effort, but it leaves your system out of commission while you send the suppressor back to the factory for repair or replacement.