If I remember correctly there was a fortran program written by Angelo Farina that could recover a ambisonic signal in 2 dimensions from a 5 microphone X setup. I mic in center and 4 mics in a square around that.
I guess we could use just omni 4 mic's in a cross to get the needed information for creating horizontal XY signals. The closer the mics are to each other the higher the frequency resololution, and the longer they are from each other the better for recovering low frequency direectivity info - this is my theory. There have been figure of 8 mics created by using 2 capsules besides each other to extract the differential preassure gradient. BR Bo-Erik -----Original Message----- From: Sursound [mailto:sursound-boun...@music.vt.edu] On Behalf Of Curtis Alcock Sent: den 13 maj 2015 07:24 To: Surround Sound discussion group Subject: Re: [Sursound] Sursound Digest, Vol 82, Issue 2 >> It's still a dreadful mike, after using plenty of ressources to >> "design" a non-optimized WXY mike. > > Yes, the positions of the mics are really suboptimal to put it mildly. > Many of them will just produce redundant information. > >> Maybe it is only me, but what was/is the < motivation > to do things >> in that way? I suspect the motivation WAS to (deliberately) provide redundant information. The author writes that "distance between microphones being 5 cm and the largest being 21.8 cm." So perhaps the goal is NOT to use all the information at any one time, but to provide enough versatility within the (library of) material for (random unknown) developers of noise reduction algorithms to test various scenarios specific to their needs. The algorithm developer could test differing beam-forming options that best met their own application by choosing which subset of the 16 microphones channels to use, depending on how great a distance they wanted between the (presumedly omnidirectional) mic ports, for example. And for developers to explore which combination of two (or more) mic ports provides optimal signal enhancement. But I'm just reading between the lines as unfortunately the website does not appear to explain any further. Which means that it's probably not necessary for me to use all 16 channels to convert to a B format file? Perhaps I only need to take a subset of the channels and use a matrix convolution software (I'm on Mac)? _______________________________________________ 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.
