jack-keyboard (virtual MIDI keyboard) jack-keyboard is a virtual MIDI keyboard - a program that allows you to send JACK MIDI events (play ;-) using your PC keyboard. It's somewhat similar to vkeybd, except it uses JACK MIDI instead of ALSA, and the default keyboard mapping is much better - it uses the same layout as trackers (like Impulse Tracker) did, so you have two and half octaves under your fingers.