Re: [LAU] Jconv

On a first mathematical level, you can see this as a sort of 'spectral' representation. Any cyclic function can be Fourier transformed into a set of harmonic frequencies, each having its level and phase. In similar way, the horizontal distribution of sound directions is a cyclic function, not of time but of the horizontal angle (azimuth) of the sources, and you can apply the same Fourier transform to it, which is how horizontal AMB works. The 'order' of an AMB system refers to how many 'harmonics' are used. For a periphonic (3D) sound distribution the 'function on a circle' becomes a 'function on the sphere', depending on two variables, azimuth and elevation. Because a sphere is not the same as a 2D hyperplane the corresponding spectral transform is not the 2D FT, but is defined by the set of 'spherical harmonics'. And here of course the more difficult maths start...