Recording studios record sounds. Recording studios are specially designed by a sound technician to achieve optimum acoustic properties. Recording studios are used by record musicians, voice-over artists for advertisements or dialogue replacement in film, television or animation. Recording studios consist of a room called the studio, where instrumentalists and vocalists perform; and a control room for sound engineers to operate professional audio for recording purposes, either analogue or digital. Recording studios also have small rooms to stock drums and electric guitar and acoustic instruments.