Lawl at you guys with overpriced superadvertised sites.
Also, a monkey can build a computer.
Repairing amps is on the circuit analysis level, compared to computers where it's just plug and chug sort of stuff. I've had numerous "bad" sound cards given to me by "technicians" that had only had a fried 7812/relative voltage regulator.
Same with power supplies, just swap the fets and the PWM chip (Most larger ones use the UC38xx series), and that "dead" 1000W PSU the "technician" threw out is now working.
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