Custom MIDI controller I designed and built for fun:

I am not a piano player, so I liked the idea of an MPC-style button grid. I figured this would also help me to think more in abstract patterns rather than keeping me confined to the C-major/A-minor scale. I only wanted six faders, as I cannot keep track of more than that at a time when recording automation of synthesizer or drum machine parameters.

16-button grid;  far left column sets the velocity, the bottom row sets the octave. The buttons to the right of the grid control the transport (play, record, stop, loop, etc.) and the jog wheel in the upper right is a rotary encoder, which allows me to scrub through a track several bars at a time.

GUTS!!! ATMega328, several 74HC955 74HC595 serial-to-parallel shift registers to control the LED matrix, a 74HC195 to decode the button matrix, and assorted logic chips to debounce and decode the quadrature signal from the rotary encoder.

The enclosure was a wooden box from a thrift shop. I cut it off at an angle with my Dremel tool, then traced out a hole on the top in which to fit a handheld "Lights Out" game. I set the upper half of the game enclosure into the panel and drew a bead around it with JB Cold Weld, sanding it smooth when it was dry. Many coats of red enamel were added to the panel, and the sides were stained with acrylic paints and sealed with polyurethane varnish (sanded between coats, of course).