Hello thereminists. I am a flutist and DSP coder and I have developed an instrument that can be played using any theremin, which generates two voices of harmony to your sound, each voice pitch-shifted by chromatic semitones as much as four octaves away. What makes it different is that it is a digital model of a tuned analog device, not a pitch tracker. It responds more strongly to notes that are closest to exact chromatic pitches. As you change pitch, its voices fade in and out as you pass each note of the equal-tempered scale. Hitting an exact chromatic pitch is as easy as simply zeroing on the strongest response, and pitch vibrato about the tonal center will result in pitch and amplitude vibrato in response. I am here to inform the theremin community of its existence, and I will custom program them for instrumentalists who would like one. You can find it on the web at http://muzemazer.com and it is called the Chromavoder.