On Thu, Oct 22, 2020 at 12:36:38PM +0100, jack reynolds wrote: > The only problem with using ambisonics mics is the high frequency limit > above which they stop working properly. A second order ambi mic reduces > this problem, but above about 7Khz the not quite coincident capsules > becomes a problem.
First order responses from an OctoMic are near perfect up to 11 kHz or so, and not perfect but still very usable even at 15 kHz. I doubt very much if there is any 'real' cardioid' doing better at that frequency and above. Certainly not if you take diffraction / reflection from the mic body and clamp into account. Anyway, have you ever considered the sort of frequency and polar response you get by combining signals from capsules spaced more than 10 cm apart ? You'll find they look quite horrible if you care to compute or measure them. You could of course object that those should never be combined, just each one sent to its own speaker. But that would mean that such a one to one mapping is the only possible way to use such signals if you want to preserve sound quality. No downmixing or anything similar (e.g. binaural) allowed. But we all know that this is not true, we all have heard very nice music recordings done with spaced mics. Even those in theory horrible frequency or polar responses resulting from spaced mics can sound quite well. Wich in turn means that this whole 'imperfect polar responses' debate is mostly academic if not irrelevant. 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.
