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About Immersive Audio Formats
Immersive audio formats use multiple channels of audio to position audio around an audience, to add a specially creative dimension to sound design. At their simplest, formats such as 5.1 and 7.1 surround allow the mixer to send varying amounts of any given track to the combination of speakers
that makes audio sound centered in front, ambient from the rear, or weighted towards the left or right of an auditorium or living room. More sophisticated “object-based” formats such as Dolby Atmos™ define a virtual soundstage on which you can actually position tracks in 3D space, and the resulting positional audio is rendered by specialized encoder/decoders to however many speakers in whichever configuration a venue happens to have.
Dolby Atmos(tm)
The traditional surround sound experience outputs a specific set of monitoring channels that requires a specific number of monitor speakers placed in particular areas of a room, which can position sound approximately within a ring around the listener. Dolby Atmos improves upon this by being an object- based sound system operating within a 3D immersive space that can accommodate a wider variety of different speaker configurations using more speakers positioned around the listener. This increases dimensionality with more precise sound placement, adding height channels to produce sound
that comes specifically from above. DaVinci Resolve supports Dolby Atmos output render formats
5.1.4 to 9.1.6.
A practical example of this difference can be heard when panning in a 7.1 mix; since you’re sending signals to specific points in a speaker array, those points are fixed. Although the physical size of rooms can be larger or smaller, the mix is always sent to those assigned point speakers, so the experience from room to room may be inconsistent. By comparison, Dolby Atmos gives re-recording mixers a way to mix to an idealized space instead of fixed speaker positions. This means a Dolby Atmos mix, when played in a Dolby Atmos room, takes into account the actual dimensions of the space, as well as the number of speakers that are used, to recalculate audio playback to suit that exact space and playback equipment, giving a more faithful recreation of the mix with much more specific sound placement, when necessary.
To give a clear example of the benefits of Dolby Atmos, think of a small theatre that has standard left, center, and right front-screen speakers. It then has four left surround and four right surround, four overhead left, and four overhead right. For this example, let’s say you have sent a sound to the surround left in Atmos, positioned at about one-half of the distance from the screen.
Now move the Atmos mix to a much larger room with twice as many monitor speakers. The new theatre has eight left surrounds, eight right surrounds, eight overhead left, and eight overhead right. Playing in this new configuration, Atmos automatically calculates the ratio of the room and the new speaker array. In this example, when that sound is reproduced at one-half of the distance from the screen, Dolby Atmos calculates the ratio of the sound in relation to the new playback setup, so the listener hears exactly what the re-recording mixer intends.