For many years, the term surround sound was common in film

The established Dolby Surround was and is a channel-based format with 5.1 speakers, 2 in front, one in the middle and 2 behind the listener. In addition, there is the "Punkt1" subwoofer for the bass. The signals are distributed to the individual loudspeakers as a percentage.

When it comes to immersive audio, there is another dimension: the height dimension. In addition to the well-known surround positions of ear level and surround plane, height speakers and planes are used to position the audio elements in a three-dimensional array that then completely surrounds the listener.

Compared to Dolby Surround 5.1, immersive systems also include height information of the sound, in a combination of channel-based and object-based formats. Every sound event, instrument or noise is given digital meta information, in which it is recorded where it is temporally in space. The projection rooms can have different loudspeaker setups, the immersive audio signal is adapted to the setup and converted by DSP computers in the amplifiers.

The two most important formats in music and film are Dolby Atmos and DTS:X

Dolby Atmos is the market leader. Here data is reduced, compressed, object-based information packed in a 7.1 data stream and unpacked accordingly during playback and calculated out again and output to the speakers. DTS:X works similarly, is mathematically more accurate than Dolby Atmos but also larger in file size. But that doesn't play a role in the listening experience.