Quantity   Component name
12 × Blue Arcade Button Sparkfun is your friend
12 × Random Chinese Momentary Button Switch for the transport controls and more shit
4 × Random Rotary Encoders From Ebay KNOBS BROS
2 × Rotary Selection Switches Change control-layouts on the fly bra, intuitive dude
1 × DIODES button matrices bra
1 × Teensy LC for the brain, the control, the power