A recording studio is a facility for sound recording and mixing. Ideally both the recording and monitoring spaces are specially designed by an acoustician to achieve optimum acoustic properties (acoustic isolation or diffusion or absorption of reflected sound that could otherwise interfere with the sound heard by the listener). Recording studios may be used by record musicians, voice over artists for advertisements or dialogue replacement in film, television or animation, foley, or to record their accompanying musical soundtracks. The typical recording studio consists of a room called the studio or live room, where instrumentalists and vocalists perform; and the control room, where sound engineers operate professional audio for analogue or digital recording to route and manipulate the sound. Often, there will be smaller rooms called isolation booths present to accommodate loud instruments such as drums or electric guitar, to keep these sounds from being audible to the microphones that are capturing the sounds from other instruments, or to provide drier rooms for recording vocals or quieter acoustic instruments.