> My theory is that the huge moving charge induced a voltage in the amp's mains primary.
First start with basic concepts even introduced in elementary school science. Lightning seeks earth ground. A path for a 20,000 amp electric surge is via a wooden church steeple destructively to earth. Wood is not a good conductor. So 20,000 amps creates a high voltage. 20,000 amps times a high voltage is high energy. Church steeple damaged.
Franklin installed a lightning rod. Now 20,000 amps is via a wire to an earthing electrode. High current creates near zero voltage. 20,000 amps times a near zero voltage is near zero energy. Nothing damaged.
Lightning seeks earth ground. A lightning strike to utility wires far down the street is a direct strike, incoming to every household appliance, destructively to earth. Appliances are not a good conductor. So lightning creates a high voltage. Lightning current times a high voltage is high energy. Appliances damaged.
Second, for over 100 years, facilities that cannot have damage installed superior earthing connected low impedance (ie 'less than 10 feet') via one 'whole house' protector. Then high current creates near zero voltage. 20,000 amps times a near zero voltage is near zero energy. No appliance is damaged.
In your case, everything that was damaged had both an incoming and an outgoing path to earth. If both current paths do not exist, then no damage. Often damage is on the outgoing path. For example, the amp. Incoming on AC mains. Outgoing on the right channel to earth via a speaker wire touching the floor. Surge passes through everything in that path; simultaneously. But only damaged is a part(s) inside the amp.
Third, one shot protectors are a scam. Either earth a surge BEFORE it can enter a building. Or a surge will go hunting for earth destructively via appliances. Earth ground electrode is your protection. Each incoming wire must connect low impedance (ie 'less than 10 feet') to that single point earth ground either via a hardwire or a protector. For reasons even demonstrated by Franklin and his lightning rod.
Nothing new. Protection has been done this way for over 100 years. 'Whole house' protectors come from other and more responsible companies including GE, Siemens, Ditek, ABB, Polyphaser, Square D, Syscom, Leviton, Delta. Siemens. and Intermatic. To name but a few. A Cutler-Hammer solution sold in Lowes and Home Depot for less than $50. A least expensive solution has also been the best. Proven by over 100 years of experience and science. So that a protector remains undamaged even after a direct lightning strike. As explained in four topmost paragraphs.
First start with basic concepts even introduced in elementary school science. Lightning seeks earth ground. A path for a 20,000 amp electric surge is via a wooden church steeple destructively to earth. Wood is not a good conductor. So 20,000 amps creates a high voltage. 20,000 amps times a high voltage is high energy. Church steeple damaged.
Franklin installed a lightning rod. Now 20,000 amps is via a wire to an earthing electrode. High current creates near zero voltage. 20,000 amps times a near zero voltage is near zero energy. Nothing damaged.
Lightning seeks earth ground. A lightning strike to utility wires far down the street is a direct strike, incoming to every household appliance, destructively to earth. Appliances are not a good conductor. So lightning creates a high voltage. Lightning current times a high voltage is high energy. Appliances damaged.
Second, for over 100 years, facilities that cannot have damage installed superior earthing connected low impedance (ie 'less than 10 feet') via one 'whole house' protector. Then high current creates near zero voltage. 20,000 amps times a near zero voltage is near zero energy. No appliance is damaged.
In your case, everything that was damaged had both an incoming and an outgoing path to earth. If both current paths do not exist, then no damage. Often damage is on the outgoing path. For example, the amp. Incoming on AC mains. Outgoing on the right channel to earth via a speaker wire touching the floor. Surge passes through everything in that path; simultaneously. But only damaged is a part(s) inside the amp.
Third, one shot protectors are a scam. Either earth a surge BEFORE it can enter a building. Or a surge will go hunting for earth destructively via appliances. Earth ground electrode is your protection. Each incoming wire must connect low impedance (ie 'less than 10 feet') to that single point earth ground either via a hardwire or a protector. For reasons even demonstrated by Franklin and his lightning rod.
Nothing new. Protection has been done this way for over 100 years. 'Whole house' protectors come from other and more responsible companies including GE, Siemens, Ditek, ABB, Polyphaser, Square D, Syscom, Leviton, Delta. Siemens. and Intermatic. To name but a few. A Cutler-Hammer solution sold in Lowes and Home Depot for less than $50. A least expensive solution has also been the best. Proven by over 100 years of experience and science. So that a protector remains undamaged even after a direct lightning strike. As explained in four topmost paragraphs.