2nd order Ambisonics to ITU-5.1 decoder

This is a two-band decoder. Crossover frequency should be around 400 Hz. It includes a 3dB front dominance but without modifying source directions. The matrix coefficients were found by a modified genetic search procedure.

The plots below show the polar patterns for C, RF, RS, and rV (at LF) or rE (at HF). Directional error for both vectors is less than 1 degree overall (and better for the front half)

Ambdec configuration, showing matrix coefficients.
Polar patterns and rV (green) at LF.
Polar patterns and rE (green) at HF.