A-format to B-format
•The A-format signals are converted to the B-format signals by matrixing:
•  W' = FLU+FRD+BLD+BRU
•X' = FLU+FRD-BLD-BRU
•Y' = FLU-FRD+BLD-BRU
•Z' = FLU-FRD-BLD+BRU
•and then applying proper filtering: