We all know and use 9-volt batteries and many of us have 48-volt phantom power on our mic preamps, but what exactly is a volt, and how did it get its name? The volt (the symbol for which is “V”) is a unit of electric potential difference or electromotive force and it was named after the physicist Alessandro Volta (1745-1827), the man who invented the first chemical battery, the voltaic pile. More precisely, the volt is defined as the potential difference across a conductor when a current of exactly one ampere dissipates one watt of power.
