IMHO it depends on how you're generating your decoder - using a fairly "evenly" spaced speaker layout that's roughly consistent with the order means that all the matrices in the maths end up well-behaved if you do a fairly simple matrix inversion. HOWEVER, it isn't obvious that this is the best way to do things in general, and can break quite badly for irregular rigs, e.g. if you have too few or many speakers for the order you're using, or if your speakers aren't spread "evenly".
... so, if you're generating your decoder with relatively simple approaches (e.g. lightly conditioned pseudo-inverse), you'll probably get best results with a rig and order that are at least roughly in line in channel count. But I consider this to be a limitation introduced by the decoder method, rather than an intrinsic necessity. (Obviously, this is a lightly veiled plug for the Rapture3D decoder ;-) Best wishes, --Richard -----Original Message----- From: sursound-boun...@music.vt.edu [mailto:sursound-boun...@music.vt.edu] On Behalf Of Augustine Leudar Sent: 09 July 2012 12:32 To: Surround Sound discussion group Subject: Re: [Sursound] higher order ambisonics over 8 to 10 loudspeakers I cant remember the formula off hand but it important ,I am told, to use the correct number of speakers for the order you are using - so if you use too many speakers for the order that can also muddy up the localisation. Someone will enlighten us Im sure but is it : the order number + 1 squared ? If thats correct you should use 9 speakers for second order ? cheers, Gus On 9 July 2012 12:17, Garth Paine <ga...@activatedspace.com> wrote: > Hi everyone > > I have been gathering lots of ambient field recordings in A-Format for a > few years using my SPS200 Soundfiled mike and a 788T. I have experimented > with playback over an 8 channel circle, and also with 3 circles of 8 at > different heights (roof, 3M, 1M), and some other arrangements. I am > currently working on 2 dance works where I want to use some of this > material and also spatialise other synthesized material. I have 8 Meyer > UPJ-1 to use in the space and may be able to get 2 more for height (not > certain adn these may not be available at all venues). > > I would like to achieve better localization than I have found easy to do > using lower order playback and wonder if it is possible to undertake higher > order playback with only 8 speakers? ALso would it make sense to have the > speakers in the circle at different heights - would that allow a hint of > the height information (I would tell the plugin where they are), or just > distort the render? > > Thanks in advance for your advice > > Cheers, > Garth Paine > ga...@activatedspace.com > > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > https://mail.music.vt.edu/mailman/private/sursound/attachments/20120709/011f a78f/attachment.html > > > _______________________________________________ > Sursound mailing list > Sursound@music.vt.edu > https://mail.music.vt.edu/mailman/listinfo/sursound > -------------- next part -------------- An HTML attachment was scrubbed... URL: <https://mail.music.vt.edu/mailman/private/sursound/attachments/20120709/0ff 7109a/attachment.html> _______________________________________________ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound _______________________________________________ Sursound mailing list Sursound@music.vt.edu https://mail.music.vt.edu/mailman/listinfo/sursound
