Writing about the harmony research without sounds and a paper to draw on is tricky, but in short, the goal is to built some tactile visual instruments / a musical system, based on a “dynamic intonation” rather a “fixed scale” , that will nicely combine the non-compromisable advantage of the Equal temperament, Tonality changes/modulation, with the advantage of natural/irregular scales (like indian ones), More rich and witty consonances.
Musical consonances are like the starry sky. The ancient Greeks just knew few stars: Only the octave, perfect fifth, and perfect fourth were viewed as consonances. Around the Renaissance people like Zarlino then started to see new stars more clearly, pure major and minor thirds, pure major sixth, etc… then the instruments and the music started to be revolutionized little by little by this knowledge. (The final point of this revolution, in the 18th century, is called “Equal Temperament”, which is today used in 99% of the musical instruments worldwide) Then since 150 years, we started to realize that the darkest parts of the sky are in fact full of stars. The problem is that the difficulty to manage different consonances together in a music, increase exponentially with their quantity, and so far nobody has managed to build a better musical system than our 250-years-old 12-notes-scale with theses new stars. (The microtonalist approach – that simply divide the octave in a bigger quantity of notes, 24, 36, or more – is not that helpful, but often lead to weird dissonant music that occasionally give headache after a while. This is because augmenting the number of notes in a fixed scale will always augment exponentially the quantity of dissonances in it, far faster than the quantity of consonances…) The solutions are a bit complex but might lead to instruments that are easy and lovely to play with.
Another important point in this research is that while playing “dynamic” just-intonation scales, the music we’re starting to experiment doesn’t have a big polyphony at the beginning, but is mostly monophonic or biphonic, and playing it using usual repetitive keyboard computer sounds is not wonderful… Therefore, the harmony research is linked with a sound synthesis research, which is looking for a “violin-like” or “saxophone-like” expression, using pressure sensing and various sensors.