On Mon, Dec 16, 2013 at 11:13:18PM -0500, Ivica Ico Bukvic wrote: Given the number of speakers used, the S.E. system can't be pure WFS except at very low frequencies. It probably uses a combination of techniques: WFS, some things based on AMB theory, delays, etc. but they won't tell you more. But the main difference to open source systems are to be found not in the rendering system, but in the one used to create and define the content. In commercial systems this will be very visual, hide the technicalities, and probably integrate with protools. It will also be closed and let you do predefined things only. All that makes it easier to use for the non-expert. Open source systems tend to provide less in this area, but will have interfaces that allow you to define your own production workflow and tools, usually via OSC. For example, the system which I developed and installed in Parma will let you control the position and smooth movements of virtual sources via OSC, but little more. Anything else has to be build on top of this. The main tool used here in Parma is a 'mixer' that instead of really mixing its inputs, controls the rendering engine instead, while also taking care of changing e.g. reverb levels and delays in function of source position. For static sources that is almost everything you need, apart from standard production tools. For more dynamic setups I either write ad-hoc code (usually Python, but you could use SC, Pd, Csound...), or plugins sending OSC from automation tracks in Ardour. A WFS system using two or more rows wouldn't be real 3D WFS, the vertical component would use conventional panning. A real 3D WFS system would require filling the walls with speakers. Ciao, -- FA A world of exhaustive, reliable metadata would be an utopia. It's also a pipe-dream, founded on self-delusion, nerd hubris and hysterically inflated market opportunities. (Cory Doctorow)

On Tue, Dec 17, 2013 at 10:14:45AM -0500, Ivica Bukvic wrote: 'Filling the gaps' with virtual speakers doesn't change things - for the same reason that you can't pull yourself up by your bootstraps. Consider the simple case of a plane wave from a direction orthogonal to the line of speakers. All speakers will get the same signal. To create a virtual speaker between every two adjacent real ones, those two would just have to get more of the same signal. So nothing changes, except at the ends of the line (and you may rediscover tapering). Ambisonic reproduction will create images 'projected on the line of speakers' a virtual source in between the speakers will appear at the same distance as the real speakers. It's possible to change this using near-field compensation, but only for low frequencies. Distance illusions can be created by exploiting psycho-acoustic effects rather than physics. I suspect systems such as S.E. are particularly good at this. Ciao, -- FA A world of exhaustive, reliable metadata would be an utopia. It's also a pipe-dream, founded on self-delusion, nerd hubris and hysterically inflated market opportunities. (Cory Doctorow)

quite between to sounds What if the denser line is positioned a distance behind the original speakers (as in the entire space is actually bigger with a denser array encircling the real physical array)? Sure, this would do nothing for an orthogonal direction, but it may improve the perception of other angles, no?