The development of sound systems began with monophonic sound radiation: one channel is emitted from one loudspeaker or speaker cabinet. This was followed by stereophony with the stereophonic sound reproduction of two sound sources from two loudspeakers or speaker boxes. Only with surround systems was 360° sound reproduction possible.
In surround sound, the loudspeakers are arranged at the front, side and rear and supplied with their own sound signals. These systems are supported by a woofer in the sound volume. The following stage of development stands for the spatial sound, the 3D sound. In addition to the front, side and rear speakers, 3D sound systems also have ceiling speakers that create another sound plane above the listener. This emphasizes the spatial sound. As a rule , two to four ceiling speakers are used in 3D sound systems.
3D sound systems such as Dolby Atmos, Auro 3D and DTS:X no longer work on a channel basis, but with audio objects that are assigned to the individual speakers in real time. Corresponding sound systems are used in cinemas and home theaters and increase the sound enjoyment.