On Sat, Sep 29, 2012 at 11:10:11PM +0200, Jörn Nettingsmeier wrote: > On 09/29/2012 01:06 AM, Augustine Leudar wrote: > >that is ..... weird. Im sure someone will have to remind me - memories of > >constructing my ambisonic microphone and encoder are already fading but > >isnt the omni W the sum of the XY and Z +/- (each with a reduced gain) ? > > no. > > in the case of a tetrahedral mic, the simplified equations are > > W = LFU + RFD + LBD + RBU > X = LFU + RFD - LBD - RBU > Y = LFU - RFD + LBD - RBU > Z = LFU - RFD - LBD + RBU
Right. If you try to recover W from X,Y,Z as defined above you'll find it's not possible. And anyway, if W were some weighted sum of X,Y,Z then it would be redundant and not be included in B-format. Another way to see this is that W represents pressure and X,Y,Z velocity, and these are independent. 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) _______________________________________________ Sursound mailing list [email protected] https://mail.music.vt.edu/mailman/listinfo/sursound
