Atmos has a 9.1 “bed" (7.1 with two ceiling arrays), and more objects than speakers. Therefore each speaker could have an object dedicated to it. Each playback space is different though, so Atmos interpolates objects between available speakers to “render" desired pan location to actual monitor speaker locations.
I suspect that if you wanted to you could set an object at each speaker’s location and send a “holistic” recording to each of those speakers. They may not be in the optimum locations for ambisonic decoders but it might not be entirely incompatible. That could be made to work with some success in a particular auditorium for which the objects match the speaker locations. The sound field might not translate so well to other Atmos rooms. Which makes me wonder: how would an ambisonic sound field would pay back in other sized and equipped Atmos rooms? I can’t answer any of Spencer’s questions properly. I do know that the Atmos RMU (renderer) takes each mono or stereo object audio channel and places or pans it around the room based on XYZ and size metadata. These positions are mapped to the available speakers based on a stored "room configuration" file in the RMU of the number and location of speakers in the particular room. These objects can coexist with a conventional “bed” of 7.1 L, C, R, Lss, Rss, Lsr, Rsr, LFE arrangement with the addition of the "overhead" two arrays of ceiling speakers, 1 running down the left center of the ceiling, and one on the right center of the ceiling (called Lts and Rts). There is practical documentation for cinema mixers at http://www.dolby.com/us/en/technologies/dolby-atmos/authoring-for-dolby-atmos-cinema-sound-manual.pdf <http://www.dolby.com/us/en/technologies/dolby-atmos/authoring-for-dolby-atmos-cinema-sound-manual.pdf> which contains specific instructions on how to use current technology, primarily Pro Tools, to prepare Atmos masters correctly. They don’t address HOA at all. Cinemas have RMU hardware in their projection booths, but there is also a software only renderer available for sound design rooms, which often have a minimal surround and overhead allotment of speakers. Doug Murray Film sound editor > On Dec 7, 2015, at 10:50 AM, Ben Bloomberg <b...@mit.edu> wrote: > > I think the default configuration is 118 objects > and two 9.1 beds. > > :/ not ideal. > > Ben > > On Mon, Dec 7, 2015 at 12:55 PM, Spencer Russell <s...@media.mit.edu> wrote: > >> Is there any technical info available about how Atmos content is >> encoded? I've seen reference to "128 channels" so does that mean things >> are encoded as up to 128 simultaneous channels coming from different >> virtual locations? How do they get re-panned for the client-side speaker >> configuration? If so are the locations movable or hard-coded in the >> format? Are there any shoot-outs out there between Atmos and HOA? It's >> hard to find technical info among all the marketing. >> >> -s >> >> On Mon, Dec 7, 2015, at 12:37 PM, Stefan Schreiber wrote: >>> Peter Lennox wrote: >>> >>>> Yes, the thinking is that a speaker-layout-agnostic format file can be >> transmitted and decoded at the client end of things, so it could end up >> being mono, stereo, surround, surround with height, large-scale surround >> (eg cinema) and so on, depending on the technical competence of the client >> machine. >>>> Of course, a lot could go wrong... >>>> >>>> >>> >>> With the limitation that audio objects alone don't define a real >>> acoustic space/environment. (You would have to render this.) >>> >>> It is good to have options. But audio objects are not very compatible >>> with holistic = real recordings? >>> >>> (Audio objects have been used for ages in game audio, including >>> rendering of reflections and simulated acoustics.) >>> >>> Dolby Atmos is actually a hybrid (C/O) format. >>> >>> >>> Best, >>> >>> Stefan >>> >>> >>> >>>> Dr. Peter Lennox >>>> Senior Lecturer in Perception >>>> College of Arts >>>> University of Derby, UK >>>> e: p.len...@derby.ac.uk >>>> t: 01332 593155 >>>> https://derby.academia.edu/peterlennox >>>> https://www.researchgate.net/profile/Peter_Lennox >>>> >>>> >>>> >>>> >>> >>> _______________________________________________ >>> Sursound mailing list >>> Sursound@music.vt.edu >>> https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, >>> edit account or options, view archives and so on. >> _______________________________________________ >> Sursound mailing list >> Sursound@music.vt.edu >> https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, >> edit account or options, view archives and so on. >> > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > <https://mail.music.vt.edu/mailman/private/sursound/attachments/20151207/d05105f0/attachment.html> > _______________________________________________ > Sursound mailing list > Sursound@music.vt.edu > https://mail.music.vt.edu/mailman/listinfo/sursound - unsubscribe here, edit > account or options, view archives and so on. -------------- next part -------------- An HTML attachment was scrubbed... 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