The Tetra analog synthesizer by Dave Smith Instruments is a very nice sounding synth but the user interface of it leaves much to be desired. This MIDI controller (designed by me, Witchmaster Creations is a name I have been using) enables editing of the Tetra a breeze.
The user interface is similar to that of DSI Evolver desktop. It features 16 knobs and a matrix style parameter list, you choose the row of parameters with 16 buttons. You can set the midi channel of the controller and control up to four different Tetras on different midi channels. It’s of course also possible to set layer to edit etc. By having 16 knobs it’s possible to edit all the steps of the built in sequencer at once.
The controller also features a display that shows the numerical values AND the description (waveform names, modulation destinations, note names etc.) to give you a clear indication of what you are doing.
Built using an Arduino UNO and has a dedicated PIC for merging midi input and midi data generated by this controller (to minimize latency for other midi data).