Review on 100W Police Air Horn Amplifier With Manual Control, Stock Horn Bypass, And Waterproof Design - Ideal For Emergency Vehicles, Trucks, And Cars With 100W Speaker Compatibility by Darrion Hudson

Why is this listed as 100 watts?Prior to installing this unit into a vehicle, I wanted to test it on the bench. Using a 14vdc - 19 amp DC supply, a Federal Signal BP100 speaker that measured 11 ohms on DC resistance from a calibrated Fluke 87V meter.Upon applying power to the yellow lead, output AC current measured 2.7 amps at 22.3 volts AC.I won't go into the formulas, but you can use google, but the power out by the math is 60.2 watts.So what does the "100w" actually apply to?