On Wed, Oct 21, 2020 at 02:37:39PM +0100, Augustine Leudar wrote: > So if you > had say, 8 ambisonics mics pointed in 8 different directions ,in order to > record that small 8th of a sphere (or in this case cube) in the direction > they are pointed in (which is what the ORTF does) - how would this work if > the decoder if a format gives spherical coordinates rather than an 8th of a > sphere/cube (hope this makes sense), and with the capsules pointing in all > directions... ?
Sorry, this doesn't make any sense... A decoder doesn't give 'spherical coordinates', it outputs signals. What makes you think that ORTF captures 'a small 8th of a sphere' ?? Each Ambisonic mic, by suitable combination of its capsule signals [1], can provide the same signals as any number of conventional capsules (omni, cardioid, fig-of-eight,...) placed at the same point in space and in any direction. So you can always replace every group of (nearly) coincident conventional capsules (e.g. an M/S pair) by an Ambisonic one and get exactly the same signals. If you use a higher order AMB mic (e.g. an OctoMic) you can even get polar patterns for which no conventional capsule equivalent exists, and which certainly provide an advantage for surround. That's all there is to it. [1] This involves some filtering as well as just summing/subtracting signals, and for good reults it requires calibration of the AMB mic's capsules. If you experimented with Ambisonics in the way you pointed out, it's no surprise you got bad results. As I've stated a number of times before, there is *a lot* of completely bogus information on Ambisonics technology floating around. Some of this stuff is at the same level of intellectual integrity as e.g. flat-earth theories. Most of it is just the results of failing to understand basic things, or of simplifying things to the point that whatever remains is 'not even wrong'. Combine that with some people having their own agenda. Ciao, -- FA _______________________________________________ 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.
