Currently, Mutabor is the largest of the projects specified here. It is a software, which permits to retune MIDI instruments dynamically. Thus phenomena are attainable also for classical key instruments, which were accessible for choirs, violins, trombones and similar instruments only.
An example is just intonation. It is well-known the phenomenon to choir leaders and singers that a choir has frequently difficulties to land on accurately the same pitch as it began. With a certain effort it is possible to trim the choir to stay at the fixed tuning. However, this phenomenon has its cause in our western music and the principle of consonance and dissonance. If one wants to use this principle meaningfully, he realizes, that this not possible this with the firmly tuned strings of a key instrument. Martin Vogel developed a tuning logic, in order to make the consonance principle accessible also for key instruments. This was implemented also for Mutabor.
Another application evolves, if one wants to quickly compare two or several tunings or to alternate them. Mutabor offers extensive assistance also in this setting with its various tuning logics.
Homepage: https://mutabor.sourceforge.io/