Hi there! You need: 1 MBHP CORE 2 MBHP AIN(one card is 32 pots and two is 64) 1 MBHP DIN (depends how many buttons you needs, one din is 32 buttons, 2 MBHP is 64 buttons) 1 MBHP DOUT(depends how many leds you needs(see above)) 1 MBHP LTC (If you want MIDI active leds. I think that it is necessary ;D for the great design of the box) And its also an MIDI interface with the MAX chip... I dont have that) Good luck! Christoffer