There was a time when people argued that theatrical (even home) sound has long been three dimensional. Maybe there are still some that make that claim. With the rise of binaural audio, Dolby Atmos and Auro 3D, sound actually is entering the third dimension. This is just a small semantic argument. Surround sound, in its traditional 5.1 and 7.1 formats, wasn’t technicallythree dimensional. It was still a two dimensional plane, but that plane was perpendicular to the screen. In a way, it made the viewing experience three dimensional. Here we had the 2D screen on the vertical plane, and the 2D sound on the horizontal. The world of the film could extend away from the screen to envelop the viewer. As the presence of three dimensional image grows in our media consumption experiences, it’s become even more important to make good use of the surround technology at our disposal. The visual experience is now as immersive as the aural.

Source: designingsound