Large area FM systems are used in public venues such as places of worship, auditoriums, cinemas, and conference facilities. Most often, the transmitter is installed as part of the public address system in an equipment room or behind the stage. The audio signal is fed to the transmitter after the input sources have been mixed. The transmitter then broadcasts the signal to the personal receivers used by the audience members who can adjust the volume to their specific needs. There is no limit to the number of receivers that can be used. The range is generally 100 to 1000 feet from the antenna. If the individual has his own personal receiver, it can be used if it is on the same frequency as the transmitter or if it tunable.