An electric ukulele has a rather small body which produces only little sound without amplification. Instead, the sound pround produced by the strings is transmitted via the end-pin jack to an electric amplifier. Unconnected to the ampflifier, an electric ukulele sounds very silent. Inside the body is a piezoelectric pickup (device) which transmutes the pressure resulting from the vibrations of the strings into electric tension. Digital tuners work similarly. Volume and register can be regulated with potentiometers.