Here’s a quick demo of the Therevox ET-4.3 continuous pitch analog instrument.
This includes a 4-mode MIDI over USB output, controlling two instances of AMsynth, an assignable expression pedal/CV input and intensity key “hold” knobs.
Inspired by the Ondes Martenot (1928) and the Electro-Theremin (1950), the ET-4 is controlled by moving a finger along a reference keyboard shaped to provide tactile feedback. The ET-4.3 takes the all-analog design and adds a modern MIDI over USB output that allows it to control software synthesesizers and other external hardware for unlimited sonic possibilities.
The ET-4.3 is priced at US $2,125. More information is available at the Therevox site.