I am planning to buy a sennheiser MKH 418S shotgun mic which records MS stereo. I am planning on using the mic with my Tascam DA-P1 DAT recorder which only has L/R XLR input and I read somewhere that in MS stereo records M signal to the L channel and the S signal on 2 other channels and later combine in post production to create the stereo sound file. My question is, do I need a dat recorder with 3 inputs to be able to record in MS stereo? I am also a bit confused about the whole MS matrix decode/encode process, can anyone explain to me how it works? do the recording hardware have to support this or can I do it via software/plugins? thanks.