Home Cinema Insight | New Sound Formats vertical axis , which is key to achieving a natural immersive sound experience . Auro 10.1 is the most efficient threelayered speaker layout that can reproduce a true 3D space based on a 5.1 system .
Auro 3D
Wilfried Van Baelan , CEO , Auro Technologies lets you know what Auro 3D can do .
How does Auro-3D differ to other 3D sound formats ?
First of all , let ’ s establish that this question is about immersive sound ( i . e . sound in 3D ), which is adding the height layer ( the missing third dimension ) and not about surround sound , which was often wrongly marketed as a 3D sound format because it uses only a 2D horizontal plane of speakers around the audience . After myself – the inventor of the Auro-3D format – referred to it as ‘ immersive sound ,’ it became the new generic term also used by Dolby Atmos and DTS : X .
We have a vertical stereo field on-screen which can deliver much more transparency and depth coming from the front channels – still the most important part of the sound reproduction . We also have a three-layered system ( while Dolby Atmos has only two layers ) that gives a much more natural spread of sound in the vertical axis ( key to a natural immersive sound experience ) with much more precise localisation which can be achieved without the use of object-based technology , which we only use where it makes sense .
How to properly set up Auro-3D for the home
Typically , there is always a place above the corner speakers of a 5.1 surround sound system . Just adding Auro-3D ’ s unique quadraphonic height layer of four speakers ( AURO 9.1 ) with an angle of at least about 25 ° is enough to have the typical Auro-3D experience .
This means that consumers don ’ t need to install the speakers in the ceiling like our competitors ’ format . A key element of a good immersive sound experience is the vertical angle . When that angle is more than 30 ° above the ear-level existing surround layer , the natural coherence in the vertical axis starts to disappear , resulting in less natural sound .
Auro 9.1 is what we suggest to install in small home theatres because the ‘ Voice of God ’ channel can be created as a phantom source in the height layer when the room is not large enough . Many people believe that sound coming from above is key to getting a natural immersive experience , but that ’ s not the case – most source sounds and their important 3D reflections are exactly between the ear-level and Auro-3D ’ s unique height layer .
But for larger home theatres or theatres with more than one row of seats , we advise adding the third layer (‘ Voice of God ’ channel ) to keep a natural spread of sound in the
What set-ups are possible with Auro-3D ?
Everything starts with Auro 8.0 , which are two quadraphonic layers above each other , but of course it is missing the centre and LFE speaker of the 5.1 system , which are crucial for playback of movies ; therefore we advise on installing at least an Auro 9.1 system . Auro 11.1 became the preferred choice by our partner Barco for the cinema industry because it adds a height centre channel on screen , with six screen channels in two vertical planes , delivering the best screen sound of all immersive formats on the market today .
The typical gap between the front and surround channels with 5.1 surround suddenly disappears when the Auro-3D height layer is installed . So the need for Auro 7.1 for the home is much less important if Auro-3D is installed . But for people who already have a 7.1 installation , they can choose Auro 13.1 , which is based on a 7.1 surround sound system . This can be achieved with channel-based sound alone , which has many advantages in the sound quality and its immersive sound experience . We can further improve it using our object-based technology ( called AuroMax ) but it only makes sense if at least 20 individual amplified speakers ( like AuroMax 22.1 or 26.1 ) are installed , which is not typical for a home cinema setup .
Top Install Tricks
An Auro-3D system , in most cases , is used in addition to an existing system / setup , so to start it ’ s always a good idea to see what equipment is already present . The height layer and / or the overhead speakers do not need to be as powerful as the main screen channels , but it ’ s important that those channels have a similar timbre , for which we advise looking into speakers from the same brand , which avoids having different ‘ colours ’ when the same sound sources are moving between the vertical layers .
The installer should follow the Auro-3D specs as best as possible . Auro-3D configurations are easy to set up as a ceiling speaker is not an obligation and thus minimises the need for undertaking in-home construction work for installation .
Common questions about setting up an Auro-3D system ?
One of the most popular questions is how to combine an Atmos and Auro setup , as people often want to combine both . What they don ’ t understand is that it kills the Auro- 3D experience , while the difference in Atmos is almost not noticeable . That ’ s because Dolby Atmos at home is based on a 2D surround sound 7.1 system with object-only in 3D , while Auro-3D has a full 3D space with channelbased sounds , which allows it to reproduce original 3D reflections . These are crucial for our brain to analyse the sound field ( distance , timbre and localisation ).
When the angle in the vertical axis becomes larger than defined by our specs , this natural vertical coherence starts disappearing . Since the ‘ object-based sources ’ of Dolby Atmos are only ‘ mono ’ sources that don ’ t have these natural 3D reflections , the exact localisation of those objects is very often not so sensitive . For that reason , you find many consumers test content playing back over both speaker layouts and they find that Dolby Atmos plays back very well over Auro-3D speaker layouts , but not vice versa . It is much better to choose an Auro-3D speaker layout rather than making a bad compromise , in our opinion .
26 | September 2016