(ampere, amplifier) Abbreviation for: 1) AMPERE, the standard unit for measurement of electrical current passing through a circuit. Cables, fuses and switches are designated by their current carrying capacity. Square pin plugs are rated at 13 Amps maximum and Round pin plugs at either 5 Amps or 15 Amps maximum, depending on the size of the pins. If a cable rated at 5 Amps is used with a load of 15 Amps, the cable will overheat and possibly catch fire. 2) AMPLIFIER - sound equipment that converts the low voltage, low current signal from a tape deck, mixer etc. into a higher current signal suitable for driving speakers. See Power Amplifier, Crossover.