[sc-users] 2nd order ambisonics in 2D setup

[Sciss <contact@xxxxxxxx>]

hallo,

i wonder how many channels one would need to transport an encoded 2nd  
order ambisonic signal, when the decoding setup is strictly 2D ... i  
know for 3D the channel num is (M + 1)^2 where M = ambisonics order,  
so 1st order is four channels W X Y Z, 2nd order is nine channels.  
but looking at DecodeB2 you can throw away the Z channel if decoding  
only two-dimensional speaker setups. so can i through away a couple  
of channels when using 2nd order with two-dimensional speaker setup?  
if i use IEM's PanAmbi2O, which channels would that be, and can i use  
DecodeAmbi2O with dummy signals (probably silent?) for the discarded  
channels?

thanks, -sciss-