Running speaker wire out to numerous outdoor speakers is like putting up a giant copper antenna and asking for nearby lightning to “hit me.” It does not take a direct strike to inject surge energy into the speaker wires. Lightning strikes as far as one quarter mile away generate enough EMP energy for the surge to travel through the air and inductively couple onto the speaker wire and travel into the home or other structure. And, once lightning finds itself inside the home it can easily destroy the amp and migrate to other equipment in the rack or home.
Contact Link Your House here for more information on how to protect your home electronics