Method and apparatus for individual control of audio to loudspeakers located from a central control

摘要

In a home or business where there is a central sound source for a stereo and one or more sets of loudspeakers which are located remote as in different rooms from the sound source. A volume control switch is mounted in conjunction with each set of loudspeakers. Within the transmission line between the sound source and each set of loudspeakers there is included a sense signal which is located at a high frequency which is beyond the range of human hearing therefore not to be heard by any human. This sense signal is compared to the audio signal from which the position of the volume control for each set of loudspeakers can be ascertained. Upon initial activation of the sound source, sound is not emitted from the remote loudspeakers upon making a memory change in the volume control for a set of loudspeakers, sound will be immediately emitted from that set of loudspeakers and only that set.